Circuit Concept Research Articles

Patrimonialização e circuitos espaciais produtivos do Museu do Amanha, Rio de Janeiro

Em tempos de globalização, o artigo propõe a aplicação do conceito de circuitos espaciais produtivos como procedimento metodológico para a análise da patrimonialização no mundo contemporâneo. O contexto em discussão envolve inter-relações dos projetos de reestruturação urbana com bens patrimoniais e, como estratégia de city marketing, políticas de patrimonialização que se valem da proliferação de equipamentos culturais, tombados ou não, para participar ativamente da indústria cultural globalizada. Por meio de pesquisa visando identificar os circuitos espaciais produtivos envolvidos na construção e operação do Museu do Amanhã, o estudo compreende a espacialização dos agentes envolvidos nessas atividades, bem como o papel desempenhado por organizações nacionais e internacionais responsáveis pela produção desse novo ícone da paisagem e do imaginário carioca.

Facilitating Conceptual Changes of High School Students regarding Concepts in Static Electricity and DC Circuits through the Use of VMSCDCCText

The purpose of this study was to find out the effectivity of using visual multimedia supported-conceptual development conceptual change text (VMS-CDCCText) in facilitating conceptual change of high school students related to the concepts in Static Electricity and DC Circuits subject matter. VMS-CDCCText consists of seven parts of the text. The method used in this study is a pre-experiment with one group pretest-posttest design. The number of research subjects was 80 students consisting of 46 female and 34 male students, at one high schools in West Java province Indonesia. Data about the state of students' conceptions were collected by conception test in the four tier test format. The results showed that the number of students who reached the type of construction and reconstruction on the two concept labels covered in the Static Electricity and two concept labels covered in the DC Circuits subject matter was above 70%. These results indicate that the use of VMS-CDCCText has a high effectiveness in facilitating the attainment of conceptual changes in construction and reconstruction types that lead to ownership of scientific conceptions.

Rail-to-Rail Timing Signals Generation Using InGaZnO TFTs For Flexible X-Ray Detector

This paper reports on-chip rail-to-rail timing signals generation thin-film circuits for the first time. These circuits, based on a-IGZO thin-film transistors (TFTs) with a simple staggered bottom gate structure, allow row and column selection of a sensor matrix embedded in a flexible radiation sensing system. They include on-chip clock generator (ring oscillator), column selector (shift register) and row-selector (a frequency divider and a shift register). They are realised with rail-to-rail logic gates with level-shifting ability that can perform inversion and NAND logic operations. These logic gates are capable of providing full output swing between supply rails, V DD and V SS , by introducing a single additional switch for each input in bootstrapping logic gates. These circuits were characterised under normal ambient atmosphere and show an improved performance compared to the conventional logic gates with diode connected load and pseudo CMOS counterparts. By using these high-performance logic gates, a complete rail-to-rail frequency divider is presented from measurements using D-Flip Flop. In order to realize a complete compact system, an on-chip ring oscillator (output clock frequency around 1 kHz) and a shift register are also presented from simulations, where these circuits show a power consumption of 1.5 mW and 0.82 mW at a supply voltage of 8 V, respectively. While the circuit concepts described here were designed for an X-ray sensing system, they can be readily expanded to other domains where flexible on-chip timing signal generation is required, such as, smart packaging, biomedical wearable devices and RFIDs.

Modern Solutions to Modeling and Optimization of the Steady State of Multi-Energy Systems

A complex solution of problem of creating mathematical models of multi-energy systems is possible using a unified approach. An approach that will ensure consistent construction of mathematical models and unification of computational algorithms. The paper presents the elements of the concept of energy circuits as a basis for unified modeling of systems of different physical nature. The existing and developed approaches to solving the problems of calculating the flow distribution in multi-energy systems are presented, based on the analysis of publications on this subject. The general structure of the mathematical model of the flow distribution in a multi-energy system and the set of optimization problems for steady-state operating conditions are described. A possible formulation of the optimization problem for the short-term operation of a multi-energy system is presented.

Small Presses and Little Magazines: A Print Culture Perspective on Modernism

Although the importance of small presses and little magazines to the development of early twentieth-century modernism has long been recognized, recent scholarship in print culture studies has enlarged this field of enquiry and challenged some of conventional literary history's assumptions about how modernist literature is defined and categorized. Drawing on developments in periodical studies, and the concept of a communications circuit for books and other print forms, this essay explores the historical significance of some prominent as well as lesser-known magazines and publishing imprints from the era of high modernism. Key topics, including advertising and censorship, are discussed in relation to a range of magazines, including the shortlived British Blast, the American Little Review, and the international Transatlantic Review, as well as ‘quality’ mainstream magazines. Overlapping networks of writers, editors and publishers also supported the spread of modernist book publishing from new presses: some, like the Black Sun Press and Hours Press, served small elite markets, while the imprints of B. W. Huebsch in America and the Hogarth Press in Britain each grew into diverse publishing enterprises, bringing modernism into the mainstream of the literary marketplace.

A Robust Scheme to Improving Security of Data using Graph Theory

With the incredible growth of using internet and other new telecommunication technologies, cryptography has be-come an absolute necessity for securing communications between two or more entities, particularly in the case of transferring confi-dential data. In the literature, many encryption systems have been proposed against attack threats. These schemes should normally overcome the concerns by ensuring confidentiality, integrity and authenticity of transmitted data. However, several of them have shown weaknesses in terms of security and complexity. Hence the need for a robust and powerful non-standard encryption algorithm to prevent any traditional opportunity to sniff data. In this work, we propose a new encryption system that perfectly meets the security requirements. The scheme is based essentially on the principles of graph theory which are very promising at plain text representations. Our approach proposes another use of the concept of Hamiltonian circuit and adjacency matrix using a shared key and a pseudo-random generator. After analysis of the experimental results, which were very promising, the technique was found to be both efficient and robust.

Design and Implementation of Low Power High Speed Symmetric Decoder Structure for SDR Applications

The key objective of this project is to design a decoder which can be used for hardware purposes. Hardware, here accompanies with software which is more we can discuss as a Software Defined Radio application. The decoder implemented here offers to new radio equipment (SDR), the flexibility of a programmable system. Nowadays, the behavior of a communication system can be modified by simply changing its software. Large tree decoder is made by reusing smaller similar sub-modules. Thus the structure is symmetric. The symmetric and regular structure of tree decoder makes the system a less complexity one. The structure obeys regularity and modularity concepts of VLSI circuit, thus is easy to fabricate using cell library elements. Design a Tree Decoder proposed architecture for SDR application on FPGA. The Structures made here are hardware synthesizable on FPGA board and are done in a respective manner. The design to be implementing by using Verilog-HDL language. The Simulation and Synthesis by using Xilinx Vivado design suite.

Algorithms of test diagnostics of valve circuits

Problem. Valve circuits are a special case of electric circuits. The concepts of the electric circuit and the set of its forming elements do not differ from the conventional ones, that is, its elements are ordinary electrical elements and so-called valves - transistors, thyristors. This article explores the ways to solve problems such as checking the status and finding the failing electrical components. The verification task can be considered as a separate case of electric circuit identification. Therefore, the evaluation of the performance of the valve circuits, the compilation of algorithms for their diagnosis is quite an urgent task. Solving this problem will allow more efficient and qualitative use of complex valve circuits, which exist in various electrical systems used in various sectors of the economy and industry. Goal. The goal is analysis and study of basic algorithms for diagnosing electrical circuits of different types. Methodology . The article deals with some algorithms for the diagnosis of valve circuits, namely: the algorithm for the diagnosis of valve circuits in the absence of restrictions on the choice of reaction sensors, the algorithm of diagnosis based on the information criterion, the algorithm of diagnosis by the method of separation. In addition, the use of current sensors for compiling a test diagnosis algorithm is considered. Results. Diagnosis of parameters can be used to detect gradual failures, to predict the state of an object, and to detect sudden failures, including those that cause a change in the structure of the circle: breakage or circuit closure. Originality . Separation of the electric circuit is proposed, which allows to reduce the information capacity of the algorithm and to simplify the analysis of states. Separation of the object of diagnosis allows to reduce the solution of complex multifactor problem to the solution of several simpler ones. In addition, the division of the circle into separate links allows to reduce the number of built-in sensors. Practical value. Diagnosis algorithms using inductive dividers allow maximum depth of defect detection without the use of built-in sensors. In addition to the influence of parallel circles on each other, the split-diagnostics algorithm is reduced for sequential check of the status of the links from the elements included in series, or each element separately. Key words: algorithm; diagnosis; method; valve; valve circle; sensor; test; failure; check; reactions of the working and faulty circle.

Teaching Circuits with an Electromechanical Adder

Topics like series and parallel circuits are typically introduced to beginning students through entirely abstract problems, such as finding the equivalent resistance of a combination of resistors. To teach these concepts in a more context-rich way, we asked students in an introductory class how they would arrange a power supply, bulb and one or two switches to make an AND gate, a NOT gate, and an OR gate. Then, we challenged them to combine these gates to make an adder circuit with two input switches and two output bulbs that could add two numbers. Finally, we built the circuit, using large relays with transparent cases so that students can actually see (and hear) how, for example, current flows through the AND gate when both input switches are thrown. For many students, this is the first time they intuitively grasp the relevance of basic circuit concepts to the complicated devices, like computers, that we use in everyday life.

Quantum interference capacitor based on double-passage Landau-Zener-Stückelberg-Majorana interferometry

The implementation of quantum technologies in electronics leads naturally to the concept of coherent single-electron circuits, in which a single charge is used coherently to provide enhanced performance. In this work, we propose a coherent single-electron device that operates as an electrically-tunable capacitor. This system exhibits a sinusoidal dependence of the capacitance with voltage, in which the amplitude of the capacitance changes and the voltage period can be tuned by electric means. The device concept is based on double-passage Landau-Zener-St\"uckelberg-Majorana interferometry of a coupled two-level system that is further tunnel-coupled to an electron reservoir. We test this model experimentally by performing Landau-Zener-St\"uckelberg-Majorana interferometry in a single-electron double quantum dot coupled to an electron reservoir and show that the voltage period of the capacitance oscillations is directly proportional to the excitation frequency and that the amplitude of the oscillations depends on the dynamical parameters of the system: intrinsic relaxation and coherence time, as well as the tunneling rate to the reservoir. Our work opens up an opportunity to use the non-linear capacitance of double quantum dots to obtain enhanced device functionalities.

Play dough circuits: a tangible and friendly medium for understanding physics

Students consider that physics is difficult because of its abstract nature and the involvement of mathematics. One of the most difficult topics is a simple direct current circuit. Physics education research shows that students learn better when they construct their own understanding of scientific ideas within the framework of their existing knowledge. To accomplish this process, students must be motivated to engage with the content actively and be able to learn from that engagement. The purpose of this research was to compare the grade 6 students’ understanding of the scientific concept of simple direct circuits before and after participating in a STEM activity that involved the building of circuits from play dough. Twenty questions from the Interpreting Resistive Electric Circuit Concepts Test were selected to evaluate students’ reasoning regarding direct current resistive electric circuits. Findings revealed that the students’ scores working with the different conditions after learning were significantly higher than they were before learning. However, analysis on learning progress showed that the group that had to create more works had higher normalized gain than the group that created less works. When the work was analysed with rubric criteria, it illustrated that more conditions caused more complexity and diversity to the work. In short, the condition or situation set to students affected work creation.

A universal approach of modelling the dielectric behaviors of percolative composite ceramics and thin films

The topological microstructures and electrical conductivities of (1-x)BaTiO3/xNi0.5Zn0.5Fe2O4 (BTO/NZFO) composite ceramics and thin films both exhibit a classic percolative behavior at the percolation threshold and can be well interpreted under the framework of percolation theory. However, their permittivities are in accordance with the Kirkpatrick model, which is contradictory with the well-established percolation model as revealed in previous studies. To elucidate this interesting phenomenon both experimentally and theoretically, a universal approach of modelling the dielectric behaviors of percolative systems was proposed by using equivalent circuit concept. Based on our approach, it can be revealed that the impedance of the conductive phase is too small to play a predominant role in the dielectric performance of the composites, rendering the measured capacitance and apparent permittivity to be giant around the percolation threshold. Only when the conductivity of the conductive phase reaches a certain value does this behavior appear, which can be satisfactorily interpreted in light of our universal model.

From simulations to real: Investigating young students’ learning and transfer from simulations to real tasks

AbstractResearch has explored the use of simulations for education and training, and attention is turning to how they might support learning in school subjects such as mathematics and science. However, existing studies have mostly concentrated on older students, and if simulations help build knowledge useful for solving problems within the simulation, rather than possible transfer beyond the simulation. This paper reports on a study investigating 5 year olds' learning transfer from simulations introducing simple circuit procedures and concepts, to equipment‐based tasks. The study explored for evidence of learning transfer, using an analytical framework that aligned transfer strategy indicators with cognitive process dimensions, to identify transfer events and understand the thinking skills students applied during them. Findings supported the learning value of simulations, indicating young students transferred procedural knowledge to the equipment tasks, with some also demonstrating basic conceptual transfer. They also suggested transfer tasks can provide opportunities to exercise higher order thinking, through activating processes including reflection, evaluation, analysis and abstraction. Such capabilities are highly valued, and central to school achievement and development of learner independence and self‐direction. Practitioner NotesWhat is already known about this topic Simulations can develop knowledge useful for solving problems within the simulation. Simulations can be effective for learning mathematics and science procedures. Between‐simulation transfer engages higher order processing. What this paper adds Evidence of young students' procedural learning transfer, from simulations to real tasks. Some evidence of young students' naïve conceptual transfer, from simulations to real tasks. Evidence of the value of transfer tasks for higher order thinking development. Implications for practice and/or policy Transfer tasks provide opportunities for young students to exercise higher order thinking and problem solving. Teachers should consider transfer tasks for extending procedural learning to real tasks. Teachers are important for scaffolding young students' concept formation during transfer tasks, to ensure accurate knowledge development. Simulations can be effective for developing transferrable procedural knowledge, but conceptual transfer should not be assumed.

The Identification of Student Misconceptions on the Concept of Electricity Using the CRI Decision Matrix Three Level Test

The purpose of this study is to determine the percentage of students who experience misconceptions (MIS), know the concept (KCC), do not know the concept (LK), Guess (LG), and not confidence (NC) in learning electricity concepts; in what subconcepts students experience misconceptions and what causes misconceptions. The object of the research was the first-level D-III students of Radiology Engineering in the first semester of the 2016/2017 school year who contracted the Basic Physics course. The study was conducted in November 2016. The method used is descriptive method. In this study the CRI Three-Tier Test decision matrix is used to identify student misconceptions. Identification is done by using a structured choice diagnostic test that is equipped with an index of student confidence in the test answers and also equipped with a column of reasons from the answers given by students. To find out the cause of the misconception conducted interviews. The results of CRI diagnostic data analysis showed that of the 37 students who were the object of research it was found that as many as 26.35% did not know the concept (LK), 20.95% knew the concept (KCC) where the students were in accordance with scientific conceptions, 0.51% students guessed LG), 40.88% of students experienced misconceptions (Mis), and 11.32% of answers to students who were not confident (NC). The highest percentage of misconception was found in the sub-principle of ohm's legal concept (41.08%), kirchhoff's legal sub-concept (41.89%) and sub-basic concepts of electric and parallel circuits (40.54%). The results of the interviews showed that the causes of the misconceptions included the character of abstract electrical concepts, lack of understanding of the concept, difficulty analyzing the sequence, and the unpreparedness of students to accept material delivered by the lecturer.

Fahr syndrome: A case series analysis

Fahr disease or Fahr syndrome is a rare neurological disorder characterized by abnormal calcified deposits in basal ganglia and cerebral cortex. As the disease progresses, it was found that lateral thalamus, dentate nucleus of cerebellum and the frontal cortex get affected as well. Aim of the study was to analyze 5 cases of Fahr syndrome highlighting any possible correlation between the progressive nature of the disease, clinical spectrum and neuroimaging data. Methods Five patients aged 19, 31, 43 and 53 and 56 were studied in Albania. They were hospitalized in the Neurology service, each showing a different clinical spectrum. One patient presented with seizures, another one with headache and two patients developed neuropsychiatric and cognitive disorders. Another patient was hospitalized for an acute stroke. After a thorough evaluation, brain computed tomography scans revealed calcifications in basal ganglia, with one case revealing calcifications in basal ganglia, globus pallidus, cerebellar white matter and frontal subcortical white matter. Results Although the progressive nature of the disease is estimated, different neurological manifestations account for different cases. Family history and comorbidities should always be kept in mind when analyzing the neurological signs and symptoms. Conclusion No clear cut correlation is found between the progressive nature of the disease, neurological manifestations and neuroimaging data. The concept of frontal subcortical circuits, a system of loops linking the basal ganglia and frontal brain regions, and functional neuroimaging may give additional data regarding the pathophysiology and clinical signs of the disease.

Short-Circuit Model for Type-IV Wind Turbine Generators With Decoupled Sequence Control

The power system planning and protection studies are becoming more challenging due to the rapid increase in penetration levels of converter-interfaced renewables. Type-IV wind turbine generators (WTGs) and photovoltaic panels are interfaced to the grid through a full-scale converter, and their short-circuit current contributions are mainly designated by the converter control and associated current limits. This paper proposes a new phasor domain modeling approach for the wind parks (WPs) with Type-IV WTGs, using the concept of control-based equivalent circuits. The proposed model precisely represents the detailed electromagnetic transient (EMT)-type model in steady state, and is able to account for the fault-ride-through function of the WTG control as well as its specific decoupled sequence control scheme in addition to the traditional coupled control scheme. Although the collector grid and WTGs inside the WP are represented with their aggregated models, the overall reactive power control structure of the WP is preserved by taking the central WP controller into account. The accuracy of the proposed model is validated through detailed EMT simulations.

A Second-Order $\Delta\Sigma$ Time-to-Digital Converter Using Highly Digital Time-Domain Arithmetic Circuits

In this brief, time-domain arithmetic circuits, such as time adder, time subtractor, and time integrator, are proposed. The concept of these time-domain circuits are explained and their non-idealities are analyzed. Using the proposed time-domain arithmetic circuits, a prototype second-order $\Delta \Sigma $ -time-to-digital converter is implemented in a 65 nm standard CMOS process. The fabricated chip achieves 1.44 ps rms of integrated noise in 1-MHz bandwidth while consuming 3.5 mW at 50 MS/s.

Small-Signal Stability Evaluation of Converter Control Modes in Low-Inertia Power Electronic Systems

Among the apparent toughness, when compared to various other small-signal approaches, is the natural linkage along with circuit concept. This makes them achievable to become attached by means of basic circuit rules. Having said that, careful focus ought to be actually spent when creating this association given that the insusceptibilities secured with linearization are local area variables, commonly referred to locally determined recommendation structures. To enable the operations of these insusceptibilities utilizing standard circuit legislations, a unified/global endorsement must be actually determined. Though this concern was actually appropriately attended to on the state-space versions, a thorough evaluation as well as an explanation relating to the linked resistances and stability effects are actually still missing. Eventually, this paper intents to describe a variety of the prospective hurdles that exist around stability study of electricity converters particularly when these are actually used in distributed age group requests

Development of Foreign Material Detection in Food Sensor Using Electrical Resistance Technique

Food inspection has been a serious matter in the food industry as the contamination by foreign materials such as metals, bone, plastics and glass in food plays a major impact on the industry. In spite of a great deal of effort to prevent mixing foreign bodies in food materials, food manufacturers have still not been able to detect them. Electrical Resistance Sensor to detect the foreign material in food detection sensor is constructed and presented in this work. This project focuses on how to design and implement the system to detect and distinguish between food and foreign material using resistance concept. The electrode plate of Electrical Resistance Sensor (ERS) is designed using COMSOL Multiphysics Software to see the electric field and contour of the electric potential of the system. The resistance value from the sensor is measured based on the AC Circuit concept. The alternating current from the sensor flows to the charge detector circuit providing the voltage corresponding to the resistance between the electrode pair. The voltage from the charge detector circuit has been amplified by the amplifier circuit to obtained DC output from an AC input signal. The voltage form circuit has been converted from the analog to digital signal using Bluetooth Electronics Application via Arduino Uno through HC-05 Bluetooth module. The Bluetooth Electronics Application is used as a graphical user interface (GUI) to display the condition of the material tested including food and foreign material to a smartphone. The experiment results show that the electrical resistance sensor are able to detect the foreign material in food by changes of the resistance value. If the food was detected with the foreign material (non-conductive), the value of resistance will decrease due to the flow of electric current.

Using a computer game to teach circuit concepts

We describe the development and use of Kirchhoff’s Revenge, a freely available computer game designed to teach circuit laws in introductory physics courses at the high-school and undergraduate level. In this case study, we describe design principles, effort involved in developing the game, as well as player experiences and feedback. We also report on concept-test results for time-independent scenarios (batteries, wires, and lightbulbs), where we find that conceptual learning gains from playing the game alone are similar to those from traditional instruction alone, but inferior to a combination of traditional instruction with investigative, physical laboratory experiments.