This paper presents modeling and simulation of maximum power point tracking (MPPT) used in solar PV power systems. The Fuzzy logic algorithm is used to minimize the error between the actual power and the estimated maximum power. The simulation model was developed and tested to investigate the effectiveness of the proposed MPPT controller. MATLAB Simulink was employed for simulation studies. The proposed system was simulated and tested successfully on a photovoltaic solar panel model. The Fuzzy logic algorithm succesfully tracking the MPPs and performs precise control under rapidly changing atmospheric conditions. Simulation results indicate the feasibility and improved functionality of the system. Keyword:Fuzzy logic algorithm Maximum power point tracking MPPT Photovoltaic Simulink Copyright © 2018 Institute of Advanced Engineering and Science.All rights reserved. Corresponding Author:Ahmad Saudi Samosir, Departement of Electrical Engineering, University of Lampung, No. 1, Jln. Prof. Soemantri Brojonegoro, Bandar Lampung, 35152, Indonesia. Email: ahmad.saudi@eng.unila.ac.id INTRODUCTIONThe growing energy demand of the world and the tremendous risk of climate change associated with the use of fossil fuels have driven research and development of alternative energy sources that are clean, efficient, renewable and environmentally friendly. Among all renewable energy sources, solar power systems attract more attention because they have several advantages such as pollution-free, low maintenance costs and low operating costs. Their sources of energy, which is derived from solar energy, are also widely available and it is free [1]- [4].In solar power system, the solar energy is directly converted into electrical energy by solar PV module. The main components of solar PV systems are solar cells made from semiconductor materials that have a photovoltaic effect, which serves to convert solar energy into direct current electricity. When exposed to sunlight; the solar panels will generate the direct current electricity, which is ready to supply power to the load. Solar Panels do not need much maintenance and have no moving parts. The unfavorable issue with solar PV systems is the high installing cost and the variation of energy form the solar panel with environmental conditions. In order to attain the maximum efficiency from the solar panel, it is important to obtain the maximum available power at any operating condition [5]. Also, the power distribution across the system has to be managed. Storage devices are used so that the energy is stored or supplied according to the availability of sufficient power and the load requirements [6].The efficiency of solar cells depends on many factors such as temperature, irradiance, spectral characteristics of sunlight, dirt, shadow, and so on. Changes in insolation on panels due to fast climatic changes such as cloudy weather and increase in ambient temperature can reduce the photovoltaic (PV) array

We study the photoresponse of Si nanoscale p–n and p–i–n diodes. As a result, we find a photon-sensitive multilevel random telegraph signal (RTS) in p–n diodes, but not in p–i–n diodes. From this fact and analysis of current jumps in the RTS, the multilevel RTS is ascribed to single photocarrier charging and discharging in a donor–acceptor pair in the depletion region. Thus, it is found that a donor–acceptor pair plays an important role in p–n junctions, while, according to our previous report, a single donor (acceptor) works as an electron (hole) trap in junctionless field-effect transistors.

We studied current-voltage characteristics of nanoscale pn diodes having the junction formed in a laterally patterned ultrathin silicon-on-insulator layer. At temperatures below 30 K, we observed random telegraph signal (RTS) in a range of forward bias. Since RTS is observed only for pn diodes, but not for pin diodes, one dopant among phosphorus donors or boron acceptors facing across the junction is likely responsible for potential changes affecting the current. Based also on potential measurements by low-temperature Kelvin probe force microscope, RTS is ascribed to trapping/detrapping of carriers by/from a single dopant near the farther edge of the depletion region.

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Intisari — Proses pemanenan buah tomat dapat dilakukan menggunakan metode visual dengan memperhatikan warna atau ukuran dari buah. Kemajuan teknologi menggunakan bantuan komputer membuat pemanenan dan pendeteksian kematangan buah tomat semakin mudah. Informasi kematangan buah tomat dapat diperoleh dengan cara pengolahan citra dengan bantuan fuzzy logic menggunakan metode Tsukamoto. Pada penelitian ini beberapa sampel buah tomat diambil nilai RGB melalui pengolahan citra sesuai dengan tingkat kematangannya, diantaranya mentah, setengah matang, dan buah matang. Setelah nilai RGB didapat maka akan diproses ke dalam fuzzy logic untuk mendapatkan informasi kematangan melalui aturan-aturan yang telah dibuat dan diintegrasikan menggunakan Raspberry Pi. Hasil penelitian ini menunjukan bahwa kondisi yang baik untuk melakukan pendeteksian buah tomat salah satunya yaitu pada kondisi indoor 100 Lux berlatar belakang gelap. Hal ini mungkin dikarenakan tidak terdapat pantulan cahaya berlebih sehingga citra yang diambil nilai RGBnya tidak terlalu tinggi dan mengurangi terjadinya kesalahan pembacaan informasi kematangan dalam proses fuzzy logic.Kata kunci — Image Processing, Fuzzy Logic, Modul Kamera Raspberry Pi.Abstract — The process of harvesting tomatoes is usually done by the visual method by looking at the color or the size of the fruit. Technological advancements by using computer assistance make harvesting and detecting the ripening process of tomatoes easier. The information of the process of Tomato’s ripening can be obtained by the image processing by using Tsukamoto Fuzzy-Logic. In this research some samples of tomatoes’ RGB values were taken through image processing in accordance with the ripening level, between unripe, under-ripe, and ripe fruit. After the RGB value is obtained, it will be processed into fuzzy logic to obtain the ripening level information through rules that have been created and integrated by using Raspberry-Pi. The result of this research indicates that a good condition for detecting tomatoes is in 100 Lux conditions with dark background. This might be because there is no excessive light reflection, so that the RGB value of the image is not too high and reduces the error of reading the ripening level in the fuzzy logic process.Keywords—  Image Processing, Fuzzy Logic, Raspberry Pi Camera Module.

Safety and comfort are needs for all human beings. Meanwhile, the crime rate is increasing. Therefore, a remote monitoring and control system is needed. This research offers a home monitoring and control system with a client-server model using NodeMCUESP-12E. The equipment design can be used to monitor the condition of the house through sensors installed in each room. Home monitoring includes motion detection using a motion sensor, detection of the condition of the house door using a magnetic sensor, and remote door locking using a solenoid. The system can be operated offline or online using an Android smart phone. The communication model used for client-server over the transport layer protocol is User Datagram Protocol (UDP), so the server can communicate simultaneously on two clients. The fastest average response time is 0.653 seconds. The communication model between a server and a cloud uses Transmission Control Protocol (TCP) so that the data sent or received by the server through the internet is more reliable. The cloud used is Firebase which has real-time database facilities and historical data. When online, sensor response time average is the fastest on an android at 3.898 seconds, response time control is the fastest average on a client at 7.157 seconds and the control response time average is the fastest on an android at 9.495 seconds. ABSTRAK: Keselamatan dan keselesaan merupakan keperluan penting untuk manusia. Sementara itu kadar jenayah pula kian meningkat. Oleh itu, kita perlu pemantauan jarak jauh dan sistem kawalan. Kajian ini merupakan sistem kawalan dan pemantauan rumah dengan model pelanggan-pelayan menggunakan NodeMCUESP-12E. Peralatan yang dibina boleh digunakan bagi mengawasi keadaan rumah melalui sensor yang dipasang dalam setiap bilik. Pemantauan rumah adalah termasuk pengesan gerakan menggunakan sensor gerakan, pengesan keadaan pintu rumah menggunakan sensor magnet, dan pengunci pintu jarak jauh menggunakan solenoid. Sistem ini boleh digunakan secara luar atau dalam talian menggunakan telefon pintar Android. Model komunikasi yang digunakan pada pelanggan-pelayan menggunakan protokol lapisan pengangkutan adalah Protokol Datagram Pengguna (UDP), oleh itu pelayan dapat berkomunikasi secara terus dengan dua pelanggan pada purata masa respon terlaju sebanyak 0.653 saat. Model komunikasi antara pelayan dan awan adalah menggunakan Protokol Kawalan Penghantaran (TCP), dengan harapan data dapat dihantar dan diterima oleh pelayan melalui internet dengan lebih kebolehpercayaan. Awan yang digunakan adalah Firebase yang mempunyai kelengkapan pengkalan data waktu nyata dan data sejarah. Melalui keadaan dalam talian, purata masa sensor bertindak balas adalah paling laju pada Android sebanyak 3.898 saat, purata kelajuan kawalan masa bertindak balas pada pelanggan adalah 7.157 saat dan purata masa kawalan tindak balas adalah paling laju pada Android sebanyak 9.495 saat.

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