1,720,958 research outputs found
Digital Tone Control Menggunakan Mikrokontroller 8-Bit
Full text linkAbstractThe quality of the audio sound system that is generated depends on the tone control. Good audio tone control signal output produces an audio signal that approaches the input audio signal. Tone controls are generally used on audio sound system devices using potentiometers as regulating devices. Potentiometers are done in charcoal powder which has varying and linear barriers. Problems that often arise in potentiometers in the form of quick wear due to frequent friction, the output of the tone control will produce a noise when the relationship between the powder charcoal and the sweeping lever is not well connected, and linearity will change if the potentiometer is dirty due to dust. Microcontroller is electronic equipment that can be programmed according to user need. With a collaboration push button, Multiplexer and Analog to digital converter (ADC), can be utilized instead of a potentiometer. Setting the potentiometer is done by pressing the digital control tune up / down button. Based on the testing of the tone control on the volume setting, the input signal has strengthened 6.02 dB. In the bass setting, a signal with a frequency of 100-1 khz is passed, while the frequency of 2.5 khz is muted. In the treble setting, the frequency passed is 2.5 khz to 16 khz
A Simple Strategy of Control DC-DC Converter as Power Supply on Household Lights
Full text linkLight emitting diode (LED) lamps are lighting lamps that have high efficiency with very low power absorption. This lighting lamp is widely used in households, the working voltage is 110-230 volts AC. Under certain conditions, LED light with the driver can also be turned on using a DC voltage at a voltage of 120-125 volts DC. Storage of electrical energy from solar cells generally uses a 12 volt batteries with a large enough current capacity from 5Ah to 400Ah. If the driver LED light is turned on by a battery or battery with a voltage of 12 volts DC from the solar cell, the driver LED light will not light up. This is because the battery / battery voltage level is not high enough to turn on the drive LED light. An electronic device in the form of a DC-DC converter can be utilized to increase the voltage from 12 volts to a higher voltage. In this paper, a DC to DC converter with a voltage multiplier using the Cockcroft-Walton method is designed to be used to turn on LED light for household lighting. After testing, the output voltage from DC to DC is 125.2 volts and the output current is 0.0465 A with a lamp load of 5 watts, while the input voltage is 3.7 volts and the current is 1.49 A
IMPLEMENTASI SINUSOIDAL PULSE WIDTH MODULATION PADA INVERTER SATU FASE BERBASIS LOOKUP TABLE MENGGUNAKAN MIKROKONTROLER 16-BIT
Full text linkInverter merupakan salah satu elemen terpenting dalam pemanfaatan energi terbarukan. Dengan menggunakan teknik pensaklaran tertentu, inverter dapat mengkonversi tegangan dc menjadi tegangan ac. Unipolar sinusoidal pulse width modulation (SPWM) merupakan metode pembangkit gelombang sinusoida yang digunakan dalam paper ini. Data pola-pola amplitudo gelombang sinusoida dalam satu siklus dihasilkan menggunakan software DsPicWorks sedangkan 5kHz merupakan frekuensi pensaklaran pada saklar daya. Hasil penelitian menunjukan metode unipolar SPWM mudah diimplementasikan dalam mikrokontroller 16-bit, selain itu bentuk tegangan keluaran inverter berupa gelombang sinusoida dengan tegangan 0-274 volt pada beban 0-340W dengan total harmonic distortion (THD) tegangan sebesar 4,41%
REGULATOR TEGANGAN MENGGUNAKAN INVERTER SATU FASA BERBASIS DIRECT DIGITAL SYNTHESIS DENGAN PENGENDALI PI DAN PWM
Full text linkElectricity consumers who are far from the power plant at the end of the distribution channel are susceptible to a decrease in electric voltage. This results in consumer electrical equipment that is sensitive to electrical voltage fluctuations damaged. Based on these problems, equipment is needed that can improve the quality of customer electricity voltage. The inverter is one of the tools that can be utilized to increase the voltage. Direct digital synthesis (DDS) is an approach used to generate SPWM signals on an inverter. The inverter output voltage is monitored by adjusting the modulation index magnitude of the SPWM generator. This research uses dsPIC30F4011 microcontroller as a system control and SPWM signal generator with feedback using PI control. The results of the study showed that the shape of the sinusoidal waveform output voltage. To produce a voltage of 225 volts ac when turned on the first time required is 3.6 seconds with a value of Kp = 0.00125 and Ki = 0.004 in the response time PI control closed loop. While the single-phase inverter output voltage of oscillates at 47 volts or 20.9%
Prototype Pengontrolan Lampu Dengan Menggunakan Ponsel Pintar Android Via Wifi Berbasis Mikrokontroler
No full textEveryone must have a rush outside the house, sometimes in a hurry even forget to turn off and turn on the light in the house during the morning or night. At times like this, of course, that makes people lazy to go back to the house to turn off the light that causes electricity waste and make time efficient to turn on the light. In this study a prototype of lighting control will be made where observations have been made about the prototype need. Then look for literature related to light control prototypes. The prototype method uses the blynk application as a light controller connected to the internet with the media via wifi. ESP-01 as a microcontroller processes commands from a smart phone which then results in controlling both the off and on the lights as well as the receiver and transmitter in the lighting control system. Thyristor switch module as an electrical switch instead of a manual switch at home to turn on or turn off the light through commands from the microcontroller. This prototype is very easy to use because through a prototype smart phone can be controlled, so this is a solution for humans to turn on or turn off the light by utilizing wifi in the house. From the experiments that have been carried out the average speed of the prototype tool receives an order from open source blynk application in 0.28 second
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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