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Every piece of music contains emotion in every sound presented. Detection of the music emotion is quite difficult to do because the emotions felt are subjective. Based on this problem, it is necessary to have an automatic classification system to detect the emotions produced in music. In this paper, an explanation of the result to develop an emotional classification system of instrumental music. This system described the process starting with the receiving an input in the form of a music file in the format wav. Furthermore, the feature extraction process is carried out using Mel-Frequency Cepstral Coefficients (MFCC). The result of the extraction of such features are used in the classification process using the K-Nearest Neighbor (K-NN). The system produced output in the form of happy, relaxed, and sad emotions. The output of the system has a classification achieved an accuracy of 97.5% for the value of k = 1, reaching an accuracy of 95% for the value of k = 2.95% and for k = 3, reaching an accuracy of up to 90%.

Resilience is an individual's ability to survive adversity and bounce back from problems experienced by the individual. Mothers who have children with ASD experience a hefty burden in caring for and nurturing their children in their daily lives. Thus, mothers of children with ASD need high resilience to have a balanced life. This paper will explain the impact of ASD on mothers' daily activities and the various factors that impact the resilience of mothers of children with ASD. Furthermore, various factors impact the resilience of mothers of children with ASD, such as acceptance, family support, social support, internal resources, and external resources, as well as the challenges of building the resilience of mothers of children with ASD in the future discussed.

The purpose of this study was to determine the regeneration activity of pancreatic beta cells by a combination of the ethanol extracts of Moringa leaves and Clove flower. These extracts prepared by maceration with ethanol as solvent . This is an experimental laboratory research by using post test only group design . The subject of this research is 40 white male rats of Wistar strain ( Rattus norvegicus ) and were conditioned DM by streptozotozine-nicotinamide induction . The rats randomly divided into 8 groups , and each group consisted of 5 rats . Combination dose of Moringa leaves and Clove flowers extracts used are 150 : 40 mg / kg body weight of mice , 100 : 80 mg / kg body weight of mice and 50 : 120 mg / kg body weight of mice . The rats were sacrificed and the pancreas taken to be made preparations histopathology , staining and observation tissues with HE and IHC methods. The results showed that the staining and observation tissues of heart with HE method acquired the positive control group , the single test group and the combination group were showing the islet on the Langerhans island of the pancreas is bigger than in the negative control group. The morphology of the island of Langerhans increasingly large indicates increasing the regeneration of the cells of the islet beta pancreas; whereas the method of IHC acquired the negative control group seen lack of display intensity of positive reaction Ag & Ab beta cells with are marked with brown cells . In the positive control group , the single test group and the combination group , seen a positive reaction of Ag & Ab insulin-producing beta cells characterized by brown cells and insulin expression dominating pancreatic island of Langerhans.

This study aimed to describe the implementation of AIK learning program with the Baitul Arqam model at the Muhammadiyah University of Surakarta in the 2019/2020 year. This study employed a qualitative approach to research. In collecting data, this study used observation, in-depth interviews, and documentation techniques, while the data validation was a triangulation of data sources and theories. This study's data analysis applied a CIPP Stufflebeam analysis. The results showed that (1) evaluating the AIK learning program with the Baitul Arqam model can be stated quite well in planning, organization, and implementation. The evaluation results on the supervision aspect of AIK learning program within the Baitul Arqam model can be unfavorable. Supervision was carried out only when students follow Baitul Arqam. Maintenance carried out after following the AIK learning with the Baitul Arqam model was not held. (2) The challenges faced by the AIK learning program with the Baitul Arqam model included: (a) the need for strategic planning, (b) qualified educators based on the standards, (c) a campus environment, and (d) an integrated supervision model.

Studi ini bertujuan mendeskripsikan wujud kesantunan berkomunikasi dalam media sosial WhatsApp antara mahasiswa dan dosen. Studi ini adalah kualitatif. Data dalam studi ini adalah kalimat-kalimat santun dalam wacana akademik di media sosial. Sumber data dalam studi ini adalah tuturan wacana akademik di media sosial. Pengumpulan data dalam studi ini menggunakan metode dokumentasi, simak, dan dilanjutkan dengan teknik catat. Analisis data dalam studi ini dilakukan dengan metode padan intralingual; padan pragmatis dan diperkuat dengan teknik analisis kesantunan Brown dan Levinson berperspektif humanis. Hasil studi ini menunjukkan tindak kesantunan positif meliputi: (1) mengucapkan terima kasih sebagai penghormatan kepada mitra tutur, 48%; (2) memberikan pertanyaan sebagai wujud perhatian kepada mitra tutur, 8%; (3) memberikan informasi kepada mitra tutur sebagai wujud kepedulian, 18%; (4) menunjukkan keoptimisan kepada mitra tutur supaya termotivasi, 4%; (5) memberikan hadiah kepada mitra tutur dengan memberikan dukungan, 4%; (6) mengucapkan salam kepada mitra tutur sebagai upaya mendoakan kebaikan kepada mitra tutur, 8%; dan (7) menggunakan penanda identitas sebagai wujud menjalin solidaritas antara penutur dan mitra tutur, 10%. Hal ini menunjukkan mahasiswa memiliki sikap penghormatan yang tinggi kepada dosen dengan menunjukkan komunikasi berna da positif. Tindak kesantunan mengucapkan terima kasih, memberikan informasi yang dibutuhkan mitra tutur, menunjukkan sikap percaya diri, mengucapkan salam merupakan wujud komunikasi yang berperspektif humanis, yakni menjunjung nilai-nilai kemanusian. Penelitian ini bermanfaat dalam membangun komunikasi pembelajaran yang berorientasi pada kesantunan berbahasa yang memartabatkan nilai-nilai humanitas dalam pembelajaran. Kata kunci: kesantunan positif, akademik, media sosial, humanis Abstract This study aims to describe the form of politeness in communicating on WhatsApp social media between students and lecturers. This study is qualitative. The data in this study are polite sentences in academic discourse on social media. The data source in this study is the speech of academic discourse on social media. Data collection in this study uses the documentation method, refer to it, and proceed with note taking technique. Data analysis in this study was carried out using the intralingual equivalent method; pragmatic equivalent and strengthened by Brown and Levinson’s politeness analysis techniques with a sweet perspective. The results of this study show positive politeness actions include: (1) Thank you for the speech partner observer 48%; (2) giving questions as a form of attention to the speech partners 8%; (3) providing information to the speech partners as a form of concern 18%; (4) showing optimism for the speech partners to be motivated 4%; (5) giving gifts to speech partners by giving support 4%; (6) greeting the speech partners in an effort to pray for the kindness of the speech partners 8%; and (7) using identity markers as a form of establishing solidarity between the speaker and the speech partner 10%.. ISSN 0854-3283 ( Print ), ISSN 2580-0353 ( Online ) , Vol. 32, No. 2, Desember 2020 323 Realisasi Tindak Kesantunan Positif dalam Wacana Akademik di Media Sosial Berperspektif Humanitas Halaman 323 — 338 (Hari Kusmanto, Nadia P. Ayu, Harun J. Prayitno, Laili E. Rahmawati, Dini R. Pratiwi, dan Tri Santoso) This shows students have a high attitude of respect for lecturers by showing positive communication. Actions of thanksgiving, giving information needed by the speech partner, showing self-con dence, greeting is a form of communication with a humanist perspective, namely upholding human values. This research is useful in building learning communication that is oriented towards language politeness that digni es human values in learning. Keywords: positive politeness, academic, social media, humanity

Background: Cerebral palsy (CP) is a collection of motor disorders caused by brain damage that occur before, during or after birth which can be caused by many factors such as, congenital, genetic, inflation, infection and poisoning during pregnancy, trauma and metabolic disorders. Children with cerebral palsy will mostly have problems with posture. Muscular spasticity found in CP children is not only found in the muscles of the limbs but also the muscles forming posture (body posture), the condition of the body shape of children with CP will be exacerbated by the omission of postures that are not functional. Taping provides convenience in initiating motion, to help people with CP be able to move easily. The objectives of this study is to determine the effect of giving correction posture taping to the ability of motion of cerebral palsy children. Methods: The design in this study is a quasi experiment with a pretest and posttest design. The research will be conducted on the CP community in Yogyakarta, namely the Wahana Cerebral Palsy Family (WKCP) for 8 weeks. The research instrument used in this study was a blank check on the basic functional ability of GMFM. Results: After getting treatment in the form of Correction Posture Taping for 8 consecutive weeks, there was an increase in the functional ability of motion during sleep by 5.1385 with P = 0.000 (α

This cross sectional study attempted to provide empirical study on interlanguage sentential negation of Indonesian EFL learners, particularly the dynamic nature viewed from the stages of development and the number of grammatical error types in each stage. The subjects were Indonesian EFL learners, consisting of four groups from different grades. The data were collected through translation test and analyzed using Lightbown & Spada's framework and error analysis framework. The result indicated that the development stages were not in line with Lightbown & Spada, instead they were represented in three stages of development. Its dynamicity was also depicted by the reduction of grammatical error types at each level. The conclusion was that the learners' interlanguage sentential negation was dynamic, developing closer and closer to the target language through three stages. It is suggested that educators not to give pressure to the learners to get things right at the first place. In addition, their instruction should match the learners' stage of development.

Character building is an important component of 2013 Curriculum learning using textbooks as a learning source. This study aims to describe character values within the 2014 and 2017 revised editions of the 2013 Curriculum-based Indonesian Language Textbook for Year 10. The source of data for this research is the 2013 Curriculum Indonesian Language Textbook (BTBI) published by the Ministry of Education and Culture (Kemendikbud). Data in this study assume the forms of words, phrases, or sentences that indicate character values, collected by observation and note-taking and analyzed with a referential identity method. The 2014 and 2017 editions of BTBI carry the same character values, namely religiousness, nationalism, independence, gotong royong, and integrity. Differences in the character value content of both textbooks lie in the sub-values of each identified character value. According to the uncovered character sub-values, the dominant character in the 2014 edition of BTBI is independence. The 2017 edition contains three equivalent character values: religiousness, nationalism, and independence. Principles of Wasatiyyat Islam reflected in BTBI for Year 10 are values of tawassut (taking the middle way), tawazun (balance between the world and the hereafter), i’tidal (straightness and uprightness), tasamuh (tolerance), musawah (egalitarianism), shura (consultation), islah (reform), aulawiyah (prioritizing), tatawwur wa ibtikar (dynamism and innovation), and tahaddur (being civilized). These values represent the courteous, peaceful and gentle nature of the Indonesian nation.

This research aims at describing errors as well as knowing the factors causing students to make an error in solving problems in the material of the Two-Variable Linear Equation System (SPLDV). This research involved 31 students from grade eight students of Indonesian junior high school. To collect the data, tests, observation, and interview methods were used . The data validity w as triangulation in which it required a co mpar ison of dat a with interviews. The technique of data analysis was in three stages , starting from data reduction, data presentation, and conclu sion . The analytical framework was developed based on the Newman error category. The results obtained are three types of errors, namely error understanding problems, transformation errors, and process skills errors. Factors causing these errors, in general, are students who find difficulties to acknowledge the meaning of the questions, students have a low level of understanding and creativity in identifying problems into mathematical models, and students' carelessness in process skills. https://doi.org/10.26803/ijlter.18.11.1 7

In line with pedagogical competencies, the purposes of this study are (1) to determine and measure the capability of Content Knowledge (CK), Pedagogical Knowledge (PK), and Pedagogical Content Knowledge (PCK) for prospective Indonesian language teacher in preparing lesson plan based on 2013 curriculum in academic year 2017/2018, and (2) to describe the implementation of the lesson plan prepared by prospective Indonesian language teachers in teaching-learning process for academic year 2017/2018. This type of research is descriptive qualitative by using the documentation method. The results showed that the Indonesian language teachers’ capability of CK was 79.11% (good), the capability of PK was 80.41% (good), and the capability of PCK was 83.2% (good). Then in the applied Learning, the teachers do not apply the teaching-learning process based on the lesson plan, but the results tend to be better than the prepared lesson plan. https://doi.org/10.26803/ijlter.18.10.16

Mostly natural disasters in Java Island such as landslides are within the vicinity of not more than 200 Km from the district capital. Cellular communications require complex systems and rather vulnerable  to cope with disasters. NVIS mode is considered as a simple radio link during disaster mitigation initiation process. It needs a valid estimation to figure out the condition of the ionosphere. There are two purposes of this study, the first of which is an attempt to find out a fact the existences of authorized HF users who still work in the band of 3 MHz – 10 MHz. The second is to integrate low cost HF radio communication, commonly available small single board computer hardware, and opensource software, to build a sounding system to evaluate the quality of NVIS channels. Prediction system such VOACAP give hourly prediction data, however it has an inherent limitation because of  nature the underlying databases is monthly average based, therefore, the estimation could not be made in a daily bases. However, a real-time channel evaluation (RTCE) able to purify maximum observed frequency (MOF) estimation, and consequently, its able to select the best available frequency for short term and real time operation. In this study, we used WSPR to perform a simple RTCE technique. Furthermore, we also reviewed the current regulatory status regarding the availability of sub-10 MHz band for NVIS radio operation. The results show that discrepancies between simulation and measurement are occurred mainly because of sporadic data in the band of 60m and 80m. However, all of the measurement results and simulations almost have the same agreement regarding the quiet period between local midnight and local sunrise. The results of measurements show that 60m band is the most reliable NVIS channel between local sunrise and local midnight. Furthermore, 100 watts is a proper transmitter power to reach the required SNR for reliable voice communication.Â

Several studies have shown that the main challenge in teaching complex systems involving many theoretical backgrounds to senior students is their lack of confidence. In this paper, we present an approach to the teaching methodology of an undergraduate course in a telecommunication study program. The first goal of this methodology is to help students understand the theoretical concepts behind wireless digital communication systems through direct practice to give them more exposure to a real system through affordable practice activities in an experiential context, utilizing an HF radio and a single-board computer (SBC). The second goal is to challenge senior students to understand the data link layer by using white box testing of the syntax of the programming language embedded in the SBC. This approach is ideally carried out based on offline and hands-on class activities, however, the pandemic condition made it unavoidable to do it online using a demonstration model. Feedback from students was collected through written comments, post-testing, including a facility index analysis, and a questionnaire that was distributed using the available e-learning system. The post-test results showed that the average score was 72 out of a maximum of 100.

Traffic accident is one of the contributing factors of the death that happened around the world. From various types of drivers that are usually found in the traffic, motorcycle drivers have a relatively higher risk compared with other types of drivers. Therefore, there is a need for a system that is capable to detect dangerous behavior from the driver and gives an alert when abnormal behavior is detected. To develop it, we choose the 2 basic sensors to detect the movement from a driver, which are Accelerometer and Gyroscope. These sensors have been integrated into a smartphone. For the classification process, we proposed an Enhanced Multi-Layer Perceptron (MLP). The complexity of the model is reduced to ensure that our proposed system will be able to work in real-time conditions and in a limited-resources environment. In our model, we use the combination of ReLU and Softmax function, two of the famous Activation function, to enhance the performance of our model. The level of accuracy of our model achieved 97.5% with an average computational time of 45 ms. This proved that our model works better than the previous research with the same dataset.

Nowadays, gender classification using voice has been implemented, for a case in the security sector. The voice of each individual has a unique character, because of the diversity in the sound spectrum, frequency, and amplitude between individual. So, the option of technical features to determine specific characteristics to identifying gender came the major issue in classifying. In this study proposed two parameters to determine gender classification based speaker’s voice. There was a fundamental frequency of the YIN algorithm and the cepstrum coefficient of the Mel Frequency Cepstral Coefficient (MFCC) with the classification of Euclidean Distance and Mahalanobis Distance. Based on the data analyzed, it has classified the data test of females on the YIN algorithm with 100% accuracy. Meanwhile, in the male data test, there were several steps to process data that was still misclassified. The first step with the YIN algorithm got an accuracy of 47.5%, then with a combination of YIN and MFCC-Euclidean Distance, the accuracy had raised to 98%. Then continued the Mahalanobis Distance classification to the combination of YIN and MFCC-Euclidean Distance, the accuracy had come 100%. So it can be concluded the parameters applied to determining gender classification based speaker’s voice affect the process and results of the classification.

Along with technological developments, interaction based on speech does not only occur between humans but also occurs between humans and computers, known as Human-Computer Interaction (HCI). Most HCI system applications focus on contextual information. Whereas in a conversation, emotions are also important information in communication. This study combined the differential MFCC with other features, namely MFCC, chroma, and mel frequency spectrogram. The highest accuracy results in the SER data test were obtained from the test when only using one feature, namely the MFCC of 95.24%. The second-best accuracy is when using delta MFCC with an accuracy of 90.18%. And the use of 4 features (MFCC, Delta MFCC, Chromagram, and Mel Spectrogram) has the lowest accuracy compared to the others, 87.58%. In addition, the use of four features also has a longer computing time.

Indonesia merupakan salah satu negara agraris dimana sebagian besar penghasilan masyarakat Indonesia yaitu dari pertanian. Untuk mempertahan harga jual hasil pertanian, maka diperlukan perhatian khusus dalam penyimpanan hasil panen di gudang terutama kadar air hasil panen. Pada penelitian dalam bentuk kegiatan pengabdian kepada masyarakat ini dibuat sebuah alat monitoring kadar air pada gabah dengan memanfaatkan mikrokontroler node MCU dan sensor kadar air yang terhubung ke internet. Data monitoring kadar air disimpan pada database dan pengguna dapat mengaksesnya melalui perangkat smartphone pada halaman website. Sehingga pengguna dapat mengakses kondisi hasil panen mereka yang ada di gudang bisa dilakukan dimana saja. Kegiatan pengabdian masyarakat dilaksanakan di Desa Kampungbaru, Nganjuk. Berdasarkan hasil implementasi dan pengujian, hasil pembacaan sensor kadar air pada gabah sebesar 14% dapat dikirim ke server dan dapat diakses oleh pengguna menggunakan smartphone.

In the last decade, Indonesia shifted from one of the cleanest countries in the world to one of the countries with high air pollution, especially in big cities like Jakarta, Surabaya, etc. This paper presents a preliminary study of the building of a smart sensor node system to monitor air quality for urban environments. Sampled air parameters were CO, CO2, and CH4. Incoming sensor data were classified using rules from the calculation of the entropy and information gain done before in the Decision Tree Algorithm rule finding steps. The classification is done on a Raspberry Pi device using conditional if-else on the programs. The if-else condition makes the program could achieve air quality results. The decision results in the form of warning alert or data reports packed on a Raspberry Pi device. By then using LoRa transceiver, a medium-range communication system, these results sent to a PC server. Reliability testing has been carried out starting from the sensors, algorithm processing capability, until the transmission process with Time Division Multiplexing technique. Data is sent alternately between one node to another. Based on the testing results, the CO sensor shows good performance at pollutant levels up to 300 ppm, so do the CO2 sensor at values up to 500 ppm, and the CH4 sensor at values up to 250 ppm. Test measurements have been carried out in outdoor environments for feasibility of the transmission system that has designed.

Amateur radio communication used widely for experimental activities or for backup when the main communication access network fail. One of the amateur radio communications is run by using the Weak Signal Propagation Reporter or WSPR system. This system is very reliable to send messages, that composed of callsign, grid locator, and powerTx on very narrow channel widths (6 Hz) and run in the very low signal-to-noise ratio (-28 dB). WSPR systems generally work on the High Frequency band such as the 80 m, 60 m, or 40 m band, and able to reach a very long distance, up to hundreds or even thousands of kilometers. In this paper, we will propose a study of the WSPR system utility on several frequency candidates in the Very High Frequency band (2m band). The system is realized by utilizing a handy talky radio with built-in antenna and raspberry pi device as a WSPR signaling processor. The system performance is analyzed at a low signal- to-noise ratio of -14.92 dB, and still success to transmit the data. In this case we sent a soil moisture data from environmental parameter for agricultural purposes and is inserted at the powerTx.

Transportation has become one of the needs of human life. One of the most used transportation in Indonesia is a motorcycle. This transportation is reliable, has a wide variety of uses, is capable of handling traffic jams, and is very economical. But motorbikes have a relatively high risk for the safety of the rider compared to cars. With driver behavior and road congestion conditions, accidents often occur. In this research, we observed the movement of the driver through a smartphone and built an application that was able to provide a warning to motorists. In this system we use 2 types of sensors, Accelerometer and Gyroscope sensors which are generally the basic features of a smartphone. We adopt a Machine Learning-based movement identification process with an Artificial Neural Network (ANN) algorithm. ANN will do what movements it does based on the data obtained from the Accelerometer and Gyroscope sensor values. The application is installed on a smartphone and put it on a vehicle with a fixed position. The device will calculate the activity based on several predetermined categories of the driver status. The status categories are normal, zig-zag, sleepy, turn right, turn left, U-turn, sudden braking, sudden acceleration, and speed bumps. The level of accuracy generated by Machine Learning using the Artificial Neural Network Algorithm in this research was 96,2%.

In the natural disaster areas, a cellular-based telecommunication system is often disrupted. Handy-Talky is a power full as an ad-hoc telecommunication system for this condition. This equipment works in the Very High Frequency (VHF) and Ultra High Frequency (UHF). The VHF band is strongly influenced by the environment where is this system implemented. This system is suitable for short-range terrestrial communication. However, to develop a very long-range communication, it needs an HF type of communication system. In this study, a transverter system was built to convert the frequency signal from VHF to HF and vice versa. The transverter system was implemented on Raspberry Pi and supported by the C programming language. Two identified processes were the transverter process of converting HF signal to VHF/UHF signal and the transverter process of converting VHF/UHF signal to HF signal. The HF gateway device was controlled by VOX mode in order for it to transmit immediately when receiving voice signal from VHF/UHF gateway. The communications between these two devices with different frequency run in half-duplex mode. The voice activity detection technique was employed to replace the user, automatically activated the HT push-to-talk radio power for the threshold value of 60 dB in SNR. The calibration was conducted on EEPIS campus. The HF transceivers were positioned in D3 building and Post-Graduate building, EEPIS. It has shown that the communication process using the transverter was successful.

Throughout 2019 it is predicted as the minimum solar cycle period. It will make conditions less favorable for HF propagation. For this reason, we carried out day by day observations throughout 2019 to examine the existence of HF NVIS channel by WSPR method between Surabaya and Jombang which is separated by approximately 70 Km away. Ionospheric Wave Radio Frequency fading or even the radio-blackout in the band of HF could be caused by an increasing the solar activity, especially C-class level or higher Solar Flare. This occurrence only affects the sunlit region, and it could finish for within several hours. From 1st January 2019 until this report is written, the significant Solar Flare only reach C-class. During ongoing one year sounding activity, we found a measurement result nearly similar with the pattern of impacted ionosphere condition based on occurring solar flare, even though the Solar Flare still in C-class level. In order to verify the Solar-flare impact to the ionosphere, we use a simple qualitative model to verify the results of SNR measurements results to a suspected 3-consecutive-days, based on the nature of Solar-flare impact phenomena. The results show a case of C-class level could impact the ionospheric condition even though another case show that C-class level Solar flare do not affect the ionospheric condition.

High Frequency (HF) Communication is very dependent on the condition of the ionosphere which changes conditions over time. 2019 is a year with minimum solar conditions marked by a lack of solar cold spots. This condition can cause interference with the propagation path of radio waves in the ionosphere. In this research, a report on HF wave propagation observations is presented using a retrospective method to determine the sporadic E intensity at minimum solar conditions. Data retrieval is done by beacon / sounding system between radio stations by using a low power signal processing software that is Weak Signal Propagation Report (WSPR). Observations were made by building 2 radio stations in Surabaya (7.30S, 112.78E) as transmitter and radio stations in Jombang (7.61S, 112.31E) as receiver. Observations were carried out for one year from November 2018 until October 2019. During the observation process, a frequency of 5.2 MHz is used and the results showed that there were several days that described a favorable phenomenon for HF communication at close range (below 500 km), namely Sporadic E. During the observation it was obtained 8 times the Sporadic E phenomenon that is quite long with a time span of occurrence between 1 hour to 3 hours. Overall observations show that in May to August is the time when most Sporadic E phenomena occur. So from this research, it can be concluded that the sporadic E phenomenon can still occur when the sun enters the minimum solar conditions.Keywords: HF, Solar Minimum, Ionospher, Sporadic E Komunikasi High Frequency (HF) sangat bergantung pada kondisi ionosfer yang mengalami perubahan kondisi dari waktu ke waktu. Tahun 2019 merupakan tahun dengan kondisi solar minimum yang ditandai dengan minimnya nilai titik dingin matahari. Kondisi ini dapat mengakibatkan gangguan pada jalur propagasi gelombang radio di lapisan ionosfer. Pada penelitian ini, disajikan laporan pengamatan propagasi gelombang HF menggunakan metode retrospektif untuk mengetahui intensitas sporadic E saat kondisi solar minimum. Pengambilan data dilakukan dengan sistem beacon / sounding antar stasiun radio dengan memanfaatkan software pengolahan sinyal daya rendah yaitu Weak Signal Propagation Report (WSPR). Pengamatan dilakukan dengan membangun 2 stasiun radio yang berada di Surabaya (7.30S, 112.78E) sebagai pemancar dan stasiun radio di Jombang (7.61S, 112.31E) sebagai penerima. Pengamatan dilakukan selama satu tahun dari bulan November 2018 sampai dengan bulan Oktober 2019. Pada proses pengamatan digunakan frekuensi 5.2 MHz dan hasilnya menunjukkan terdapat beberapa hari yang menggambarkan fenomena menguntungkan untuk komunikasi HF jarak dekat (dibawah 500 km) yaitu Sporadic E. Selama pengamatan telah didapatkan 8 kali fenomena Sporadic E yang cukup lama dengan rentang waktu kejadian antara 1 jam hingga 3 jam. Secara keseluruhan hasil pengamatan menunjukkan bahwa pada bulan Mei hingga bulan Agustus merupakan waktu paling banyak terjadinya fenomena Sporadic E. Sehingga dari penelitian ini dapat disimpulkan bahwa fenomena sporadic E masih bisa terjadi ketika matahari memasuki kondisi solar minimum.Kata kunci: HF, Solar Minimum, Ionosfer, Sporadic E

News hoaks rife produced and spread on social media among young people. The news can trigger disputes and threaten social disintegration. The existence of this phenomenon is due to inaccurate people sorting out news that is shared on social media. Based on the above phenomenon community service aims (1) to socialize news sorting strategies: hoaks, (2) to socialize politeness in spreading news on social media, and (3) to train young people in writing news on social media. These community service activities are carried out in Menjing Village, Jenawi District, Karanganyar Regency. Participants in this community service are members of Karangtaruna Menjing Village, Jenawi District, Karanganyar Regency. The strategy in community service is through workshops and hands-on practice.

In this paper, we evaluated the OFDM performance with Non-uniform Modulation. Then the effect of multipath fading channel analyzed using Additive White Gaussian Noise (AWGN). The types of modulations are Binary phase-shift keying (BPSK), Quadrature phase-shift keying (QPSK) and 16-Quadrature Amplitude Modulation (16-QAM). These modulation techniques were used to develop Nonuniform modulation of OFDM systems. In the simulation results, by maintaining a BER value of 0.001 this system is able to transmit 14443000 bits. Meanwhile, when it is sent by using fixed modulation such as BPSK, QPSK, and 16-QAM respectively i.e. 5252000 bits, 10504000 bits, and 21008000 bits on the same bit error rate (BER) value. The 16-QAM modulation is capable to transmit more bits, but this scheme requires more power. However, Non-uniform Modulation is able to improve bits efficiently with higher data rate compared to fixed modulation techniques.

The Ionosphere layer is used as a reflective mirror of the HF radio communications system. They have dynamic characteristics that are constantly changing at any time and place. It is need a reliable prediction system to be able to estimate the condition of the ionosphere. The term "forecast" is adopted for the practical schemes which are based on solar-terrestrial relations. In the case of zero lead-time, the forecast becomes a real-time probing of ionosphere, or well known as Real Time Channel Evaluation (RTCE) for HF communication. The term "now-casting" also used to describe an observation-intensive approach at very short term (up to one hour) ionopheric forecasting. Since the era of the 2000s the HF radio has advanced to be an intelligent HF radio system that is able to adapt to the condition of propagation at any time in order to maintain the quality of communication performance. The main component of the intelligent HF radio implementation is a low-power sounding/beacon system to probe the propagation conditions of each available HF channel. Implementation of sounding /beacon technology with small signal was of course still very secret, since then a group of scientists Amateur Radio member introduce/unlock this beacon/ sounding technology, which then called WSPR. With this openness of WSPR technology, we will replicate and integrate this small signal beacon/sounding technology in an intelligent HF communications system that is expected to be of immediate benefit to open communications in mountain-covered areas, in NVIS mode, or directly build HF radio networks throughout Indonesia in the sky wave mode, to respond to disaster mitigation. In this study we tried to carry out a simple probing/sounding technique by using WSPR. We concluded that the SNR of observations values are comparable with those of VOACAP simulation software Furthermore, we found that there is no difference observations results between two receivers located more than 100 Km away. We also concluded that both receivers only received sky wave signals.

Skema pembangkitan secret key yang memanfaatkan keacakan kanal wireless merupakan alternatif yang sangat menjanjikan untuk membangun jalur komunikasi yang aman. Beberapa perangkat wireless digunakan untuk mendapatkan parameter kanal tersebut. Namun, permasalahan yang terjadi adalah pengukuran yang dihasilkan tidak presisi sehingga menimbulkan perbedaan secret key antara dua pengguna. Salah satu upaya yang dapat dilakukan adalah melakukan praproses data sebelum dikuantisasi sehingga dapat meningkatkan kemiripan ( reciprocity ) parameter kanal hasil pengukuran. Pada makalah ini dilakukan investigasi secara detail terhadap pengaruh penggunaan salah satu metode praproses, yaitu hierarchical clustering , terhadap kinerja skema pembangkitan secret key di lingkungan indoor dengan dua variasi skenario. Hasil pengujian yang dilakukan menunjukkan bahwa penggunaan metode praproses dapat meningkatkan kemiripan parameter kanal hasil pengukuran yang ditunjukkan dengan peningkatan nilai korelasi hingga 20%. Selain itu, ketidakcocokan bit yang dihasilkan juga semakin menurun dengan nilai key disagrement rate (KDR) maksimal sebesar 20%.

Many Indonesian teachers of Senior High School have used a lecturing method. Indonesian learning, it is necessary for them to implement an appropriate method and have a high creativity as well as make innovation. For them, a cooperative-based learning innovation is considered difficult and costly. Therefore, they remain to implement a lecturing method. The problems are that a cooperative-based learning has seldom been implemented and they have frequently used a lecturing method. In Indonesian learning, thus, it is necessary to implement a new strategy, called paragraph development and questions-answers between students. The strategy makes the students active, creative, and pleasurable because it focuses on cooperation in its implementation.

Adaptive modulation is a powerful technique to improve the power efficiency and to increase the data rate of communication system in the underwater acoustic channel, which has a time varying characteristics. In this paper we propose an OFDM transmission system with adaptive modulation schemes, i.e. BPSK, QPSK, and 16-QAM. The system has ability to change the modulation scheme adaptively based on the signal-to-noise ratio (SNR), while maintaining the bit error rate (BER) under 0.01. The evaluation is conducted with simulation for the flat fading channel condition, and the system showed a good performance. It show that the system has ability to change the modulation scheme adaptively, and improve the channel capacity for certain value.

Nowadays, acoustic technology Is used In many sectors of human life. One of acoustic benefit is to know mechanical property of material, such kind of liquid and solid. One of mechanical property is acoustic impedance. Several methods are used to estimate acoustic impedance of material. Most of them use high focused ultrasound transducer, and utilize pure water as a common coupling material. However, this type of transducer is still expensive. Another type of ultrasound so called range finder ultrasound (RFU) is very cheap transducer. It is usually use to measure distance and place localization for its applications. Since RFU utilizing air as a coupling material, RFU became to a very sensitive sensor. Small displacement and small difference of distance from the sensor will produce a massive different of measurement. Hence, an accurate and precision method should be built for best result of measurement. In this paper, we utilized range finder ultrasound (RFU) sensor to estimate acoustic impedance of several saline solutions. Based on theoretical, the denser the solution the higher the acoustic impedance. From the experiment, it can be obtained that the higher the acoustic impedance of saline solutions the higher the echo signal that is received by receiver transducer. A characterization conversion curve was successfully developed from the experiment. However, assuming one plane wave for this type of transducer produced significant error. Detail discussion related to this research is presented in this paper.

The underwater acoustic communication is characterized with multipath channel affected by the reflection signal from the surface and the bottom, and the ambient noise of the underwater environment which depend on the condition where the measurement has been conducted. This paper presents a performance analysis of BPSK system in the underwater acoustic channel environment with the additive Laplacian noise model. Performance has been evaluated with the measurement data of ambient noise from two diferent location, ie. Mangrove river and Kenjeran beach. The bit error rate (BER) performance is very close to the probability of error (Pe) of multipath channel with additive Laplacian noise model. When compared to the Gaussian noise model, this system need more 2–4 dB to achieved the same value of BER.

Pada makalah ini diusulkan suatu model pembelajaran di laboratorium untuk mata kuliah pengolahan sinyal dengan memanfaatkan platform Mini PC, yang dalam hal ini adalah Raspberry pi. Strategi ini dipilih dengan tujuan untuk mengurangi kesenjangan yang sering terjadi di dalam proses pembelajaran dan memanfaatkan trend teknologi device yang semakin mudah diperoleh dengan harga terjangkau. Ada tiga modul yang disajikan, yang pertama adalah perancangan filter digital, yang kedua adalah prediksi voice-unvoice, dan yang ketiga adalah estimasi nilai pitch frekuensi. Modul yang dibangun diharapkan dapat membantu proses pemahaman sistem pengolahan sinyal, yang pada umumnya sering ditemui jika hanya menggunakan metode pendekatan matematik atau model simulasi perangkat lunak.

In this paper, presented an OFDM performance evaluation with the Non-uniform Coded-Modulation in the underwater acoustic channel in shallow water. A row of binary information is encoded by BCH code (7.4) for error correction and combined with Non-uniform modulation which is the result of modification of the subcarrier arrangement of the OFDM standard IEEE 802.11a. Modeling uses 52 subcarriers consisting of 4 pilots and 48 subcarrier data which are divided into three parts, i.e.: 24 subcarrier data with 16-Quadrature Amplitude Modulation (16-QAM) modulation, 12 subcarrier data with Quadrature phase-shift keying (QPSK) modulation and 12 other data subcarriers with Binary key-shift keying (BPSK) modulation. The channel type used describes the Additive White Gaussian Noise (AWGN) condition and is the result of measurement data. The analysis is done in terms of Signal-to-Noise-Ratio (SNR) and Bit Error Rate (BER) show that the value of the error rate of 0.001, modulation of BPSK, QPSK, 16-QAM, and Non-uniform modulation required the power each 5 dB, 8.5 dB, 10.3 dB, and 7.9 dB. However, the proposed system is able to suppress the required power up to 6 dB. The proposed system also shows better performance than fixed modulation and Non-uniform Modulation, which in this case with low power to achieve the same error rate. In addition, the proposed system has a coding gain of 1.9 dB compared to a non-uniform modulation system. Real testing is also done with measurement data at Mangrove estuary, Surabaya. The results show performance similar to simulations performed on Gaussian noise channels.

Occupational therapy students in Indonesia experienced new challenges when praticing their fieldwork at a disaster site. Through a volunteer project, lecturers led students to understand the needs of people following disaster and learn how to use their skills as occupational therapists when working in the disaster arena.The role of occupational therapy in disaster may include analyzing occupation and activities in order to maximizing client performance, evaluating functional abilities related to specific occupation and constructing physical and psychosocial environment to enable social participation (AOTA 2006). During the Yogjakarta disaster of 2006, students undertook a variety of roles depending on the particular situation they found themselves in.Students learned that they should work with local partners and local community as much as possible in the emergency relief process: Local partner and local community speak the language, know the local culture and the area (Sabdono 2006). The students ...