Daftar accepted manuscript:

**Audio Bio Harmonic with WT5001 Smartchipusing Solar Cell**

**Author(s): **Nur Kadarisman, Fitria Ayu Sulistiani, Wipsar Sunu Brams Dwandaru, Rhyko Irawan Wisnuwijaya, dan Agus Sugiarto

**ABSTRAK**: The design of audio bio harmonic (ABH) with smartchip WT5001 using solar cell technology in the form of ABH instrumentation with an electricity resource derived from solar energy has been successfully created and tested, which includes (i) testing the peak frequency of sound and sound output, and (ii) emptying and charging tests to determine the effectiveness of the use of the solar cell as the power provider. The ABH system consists of (i) a sound generator device composed of WT5001 sound modules, amplifiers, and horn speakers, and (ii) structured power supply devices for solar cell modules, charger controllers, and batteries for storing power. The test results of the peak frequency for the insect (garengpung) sound files and the output sound of the ABH device indicate a deviation of peak frequency of 13.46 Hz to140.81 Hz. The 15 hours emptying test results in on mode with battery charging for 7 hours shows that the use of 10Wp solar cell is effective to provide electrical powerin ABH tool operation.

**Analisis Resolusi Spatial Citra Ultrasonografi (USG) pada Arah Tangensial Radiasi Citra menggunakan Phantom Berbasis Silicon Rubber**

**Author(s): **Victory Immanuel Ratar, Surya Suryasatriya Trihandaru, dan Giner Maslebu

**ABSTRAK**:Ultrasound is widely used in diagnostic imaging, therefore quality control (QC) of ultrasound images is important. One of the QC parameter is spatial resolution that can be analyzed by calculating the distance between two nearby object in the tangential direction of radiation. The image that is produced by the curved array transducer will produce a circular shaped image and the coordinates of the object isnt in the cartesian coordinate system because it adapts to the surface of the transducer.The image must be transformed with a circle equation approach to calculate the distance between two nearby object. This study was using a Mindray 3D ultrasound model: DP- 10 with transducer model: 35C50EB, and phantom instruments made from a mixture of 99 ml silicon rubber and 1 ml catalyst. The acquisition data used a fixed frequency of 4.5 MHz, fixed gain of168 dB, and fixed depth of 3,3 cm. The result found that the measurement of objects in A area was (0.85 0.01) cm,B area was (0.62 0.07) cm, and C area was (0.48 0.06) cm. The values obtained still meet the standards set by American Association of Physicist in Medicine (AAPM).

**Karakterisasi Stabilitas Termal Kaolin Tatakan Kalimantan Selatan**

**Author(s): **Muhammad Saukani, Izzatus Sholehah, Saifullah Arief, dan Sadang Husein

**ABSTRAK**:This research is to characterize thermal stability of Kaolin from Tatakan, South Borneo. This research have been done by discussing the thermal treatment provided for kaolin clay and it used as a geopolymer base material. The FTIR, DSC-TGA, and XRD characterize the prepared kaolin clay. The DSC-TGA analysis shows that predehydroxylation occurred at temperatures of 50-120 ° C. In addition, the dehydroxylation process started at 430 - 650° C. However, the most stable condition is at 700 - 900 ° C. Calcination temperature at kaolin clay was given at 650° C, 750 ° C, and 850 ° C with dwell time of 1, 3, and 5 hours. After that, the calcination clay had characterized by FTIR and XRD. The FTIR results showed that all thermal treatments of metakaolin have formed. It was marked by the loss of the characteristic peak of kaolin with wavenumbers of 3600 cm-1 and 1600 cm-1. Thermal treatment at a temperature of 750 ̊ C with a holding time of 3 hours showed the largest amorphous phase formed, which was characterized by a decrease in the highest percentage of transmittance. The crystalline peak of kaolin XRD data at 750 ̊C shows that the peak of the crystalline phase of kaolinite was lost. It indicates that metakaolin has formed. Based on the results, it shows that the optimum thermal temperature that given to the kaolin Tatakan to create reactive metakaolin is 750 ° C for 3 hours.

**Inspeksi Material menggunakan Mikro-Radiografi Sinar-X Digital melalui Pengukuran Densitas**

**Author(s): **Prasetyo Listiaji dan Gede Bayu Suparta

**ABSTRAK**:X-ray digital radiography is a non-destructive digital imaging technique that utilizes X-ray radiation that penetrates material objects. This technique can be used to analyze the internal structure and composition of objects properly. Research has been carried out on material inspection using X-ray digital micro-radiography that has been developed in the Physics Department, FMIPA UGM. Material samples inspected were2B and HB pencils. All samples were irradiated by X-rays with a tube voltage of 30 kV and a filament current of 20 mA. Several images were taken for each sample, then averaged and calculated the grayscale value (intensity). Density was calculated based on variations in the intensity difference that passes through the pencil. The radiographic image showed that the internal structure of the pencil object, were wood and graphite can be distinguished. The measurement results were obtained for HB pencils, the value of the graphite density of HB pencils was (2.52 0.02) g/cm3 and graphite density of 2B pencils was (1.84 0.02) g/cm3. The results of density different between HBgraphiteand 2B graphite indicate that X-ray radiography techniques can be an alternative for material inspection purposes and density measurement.

Investigasi Difusi Pada Sistem Urinari Untuk Gangguan Fungsi Ginjal Model Empat Kompartemen Menggunakan Metode Monte Carlo

**Author(s): **Jovi Yuzzer Budiman, Jodelin Muninggar,Adita Sutresno

**ABSTRAK**:Kidney is a pair of organ in our urinary system that function to filter blood and urine establishment through filtration, reabsorption and secretion process.Formation of urine is done through one of processes, named tubular reabsorption. This process is a process of diffusion, passively and facilitated. The process happens in tubular reabsorption in kidney can be simulated by using Monte Carlo Cell simulation. Making model of 4 compartments consist of blood vessel, 2 kidneys with one kidney experiencing decreased function of kidney and bladder. Two kidney compartments with one of it experiencing decreased function affect the diffusion process that happens in substance reabsorption process in kidney.The purpose of this research is to study the diffusion process which happens in kidney by selecting several fixed variable and indicators which will be inspected by using Monte Carlo Cell simulation. The use of Monte Carlo Cell simulation enable to try any probabilities that occur in diffusion process of filtration, reabsorption and secretion processin kidney. The result of this research shows that the fewer number of molecules, the slower the molecular displacement and also the fewer number of surface molecules, the slower the molecular displacements.

**Studi Difusi Ca ^{2+} Pada Sinapis Menggunakan Metode Monte Carlo Cell**

**Author(s): **Ester Ratna Sari,Giner Maslebu, dan Adita Sutresno

**ABSTRAK**:Diffusion process became one of the important mechanisms in the human body system, such as in the nervous system which is the Ca^{2+}diffusion in the synapses.This research aims to study the Ca^{2+}diffusion process if Gd inhibits Ca^{2+}channel in pre-synapses. This study did not use Gd, but it was modeled with various numbers of Ca^{2+} channels. The less number of Ca^{2+}opened channels described the more Gd which inhibited Ca^{2+} channels. The Monte Carlo Cell Method (MCell) was used in this study. The synapses model was made using Blender 2.76b; consisted of two compartments illustrated with two circles. The molecule in the outside pre-synapses compartment interacted with the molecular surface of the pre-synapses compartment and resulted in a molecule in pre-synapses. The result of the simulation process for the molecules reached half of the variations in the number of total area channels. The time needed being 0.65s, 0.34s, 0.24s, and 0.18s, from the smallest to the biggest respectively. The times needed for density variations from big to small were 0.337s, 0.362s, and 0.364s respectively. The number of the diffused molecules in the backward rate variation within the same time was 3928, 3626, 2037, and 529 molecules respectively.

**The synthesis of TiO _{2} nanoparticles powder by Milling and Coprecipitation Mixed Method**

**Author(s): **Maya Puspitasari Izaak, Yohanes Edi Gunanto, dan Henni Sitompul

**ABSTRAK**:Ilmenite type Fe_{2}O_{3} waste (which is processed from natural iron sand) was processed into TiO_{2} nanoparticles powder carried out by leaching with HCl and then using high-energy milling (HEM) for 50 hours. The characteristics of the powder such as particle size, size distribution and phases were analyzed using various techniques such as XRD, SEM, EDS and particle size analyzer. Synthesis and characterization of ilmenite type iron sand have been successfully made into TiO_{2} by milling and coprecipitation mixed method. The purity level of TiO_{2} was obtained by 85.01%. Particle size of TiO_{2} was approximately 500 nm.

**Perbandingan Citra Hasil Rekonstruksi Metode Newton-Raphson dan Landweber pada Electrical Capacitance Tomography: Analisis Resolusi dan Akurasi**

**Author(s):**Rifang Pri Asmara, Agung Tjahjo Nugroho, dan Endhah Purwandari

**ABSTRAK**:The Electrical Capacitance Tomography sistem has been designed using Finite Difference Method as forward problem based solution. Accuracy of the solution have also determined with analitical method. The recontruction proses using Landweber and Newton-Raphson method has been conducted, so that a comparation of resolution and accuracy of the resulting image have obtained. The results of this research, indicate that the accuracy of Finite Difference Method by cutting a line on a domain object, was obtained at 90.57% on the horizontal line and at 87.43% on the vertical line. The result of the recontruction process based on Newton-Raphson method produced an accuracy of 98%, while the Landweber method only gained 88%. Two objects can be distinguished well using the Newton-Raphson method, when they are at least 3 cm apart. Meandwhile, the other method is only able to distinguish two objects, at a minimum distance of 8 cm.

**Analisis Periodesitas Gempa Bumi Diwilayah Kabupaten Lombok Barat Dengan Menggunakan Metode Statistik Dan Transformasi Wavelet**

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**Author(s): ****Fatimatuzzahrah ^{1}, Lalu A. Didik^{2}, Bahtiar^{3}**

**ABSTRAK**:This research is experimental research. Where the aim is to find out the first variotion of the a- vuale and the –b vuale, the second is to know the earthquake frequency whit the statistical method and wavelet transformation. And the third to analyze the results of the statistical method and wavelet transformation in the west Lombok regency. The method used to determine the earthquake periodicity in the study is the statistical method and the wavelet transformation. Statistical methods with Zmap software are used to determine –a values, -b vuales, and earthquake periodicity. The wavelet transformation method uses skeweness, Box Cox transformation, and continyu wavelet transformation to calculate earthquake periodicity. This study uses data from BMKG and the National Earthquake International Center (NIEC) for the area between the epicenter of 1150.46-1160.20 BT, and 80.25 to 80.55 LS from 22 January 2014 to 30 October 2018. Statistical analysis produces parameters related to saismic conditions (seismic) and tectonic research area. The parameter consists of a vuale –a around 5,5 – 2 the –b vuale of 0,9 – 1,8. Both of these parameters shwo a rare earthquake and quite high stress on the plate. Periodicity based on the results of statistical analysis is around 40-60 years for magnitude 5,5 SR. with the wavelet transformation method, the periodecity of 30 years and 60 years is obtained for earthquakes with magnitude 5,5 SR. these results indicate that the two methods produce almost the same periodecity values.

**Analisa Akurasi Sistem sensor DHT22 berbasis Arduino Terhadap Thermohygrometer Standar**

**Author(s): **Fitri Puspasari, Trias Prima Satya, Unan Yusmaniar Oktiawati, Imam Fahrurrozi, Hristina Prisyanti

**ABSTRAK**:The research of temperature and humidity comparison test using DHT22 sensor instrument based on Arduino Uno by Thermohigrometer. The background of this research problem is the development of increasingly advanced technology to facilitate measurement of temperature and humidity using DHT22 sensor based on Arduino. The aims of this tesearch was to knowing the sensor performance and comparing measurement result between DHT 22 sensor and standard *thermohygrometer*. The experiment was done using 5 times repeatability method at each room temperature variation. Comparison of the results of the average error value in the measurement of temperature and humidity between the DHT22 sensor with a standard Thermohygrometer obtained a value of 2.99% for humidity and -2.31% for temperature.

**ANALISIS NUMERIK PERANCANGAN PLTA PICO-HYDRO MENGGUNAKAN TABUNG HYDROCYCLONE DAN TURBIN KAPLAN DENGAN METODE RUNGE-KUTTA**

**Author(s): Indah Permatasari ^{(1)}, Abdul Hakim Prima Yuniarto**

**ABSTRAK**:Designing of the Pico-hydrowater Power Plan which uses Kaplan turbine applies water flow within Hydrocyclone tube. Kaplan turbines can movewith angularvelocity following fluid velocity analyzing the movement converter system. Equation of movement formulated by applying Euler-Lagrange therefore generating a differential equation. The differential equation iterated by Runge-Kutta Method which is one of the numerical solution.The movement converter system consist of 5 wheels with 1st wheel spindle with 2nd wheel. The 2nd and 3rd wheels are interconnected and the 4th wheel is connected to the 5th wheel to generate electricity generation. The results obtained by the flow of water can rotate Kaplan turbines with a force of 50N. Maximum angular velocity of 5500 rad/s on the 5th wheel. The rotation speed of the wheels on the converter system will increase with time.

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