cover
Contact Name
Ali Khumaeni
Contact Email
khumaeni@fisika.fsm.undip.ac.id
Phone
+62247474754
Journal Mail Official
jpa@live.undip.ac.id
Editorial Address
Department of Physics Faculty of Science and Mathematics Diponegoro University Jl Prof Soedharto SH, Tembalang, Semarang, Indonesia
Location
Kota semarang,
Jawa tengah
INDONESIA
Journal of Physics and Its Applications
Published by Universitas Diponegoro
ISSN : -     EISSN : 26225956     DOI : 10.14710
Core Subject : Science,
Journal of Physics and Its Applications (JPA) (e-ISSN: 2622-5956) is open access, International peer-reviewed journal that publishes high-novelty and original research papers and review papers in the field of physics including Radiation Physics, Materials, Geophysics, Theoretical Physics, Instrumentation and Electronics, Medical Physics, Biomedical Physics, Chemical Physics, Mathematical Physics, and Applied Physics. The JPA publishes two issues annually (May and November). The journal is published by Department of Physics, Faculty of Science and Mathematics, Diponegoro University, Indonesia.
Articles 23 Documents
The Electric Susceptibility of Bi-Layers Ferroelectrics Gunawan, Vincensius; Umiati, Ngurah Ayu Ketut; Subagio, Agus
Journal of Physics and Its Applications Vol 1, No 2 (2019): May 2019
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v1i2.4860

Abstract

In order to enhance insight of layered structure, we perform numerical calculation to obtain the dynamic electric susceptibility in bi-layers ferroelectrics. Since susceptibility is a parameter which gives response to the external field, then determination of this parameter is important. A lattice model is employed to slice bilayer structure into several lattices.  Then, Landau-Khalatnikov equation of motion is used in each lattice to construct a matrix equation of equation of motion.  The solution is obtained by applying entire-cell effective medium.  We find that the homogeneity of dynamic polarization is different from homogeneity of the single individual layer due to the existence of interlayer interaction.  As a result, the electric susceptibility is also altered.  It is also noticed that there is a relation between the homogeneity of dynamic polarization and the value of electric susceptibility near resonant frequency.  The higher the homogeneity, the bigger the values of susceptibility will be. 
Synthesis of Zn-Fe nanoparticles using pulse laser ablation as a contrast agent in magnetic resonance imaging Hikmantiyah, Nurul; Hidayanto, Eko; Khumaeni, Ali
Journal of Physics and Its Applications Vol 2, No 1 (2019): November 2019
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v2i1.6458

Abstract

Synthesis of zinc oxide nanoparticles, iron oxide nanoparticles and Zn-Fe nanoparticles using pulse laser ablation method has been conducted. Experimentally, a pulse Nd:YAG laser (1064 nm, 7 ns, 35 mJ) was directed and focused on a metal plates of pure Zn and Fe, which are placed in the liquid medium of polyvinyl pyrrolidone (PVP). The PVP functions as a stabilizer agent. The results show that the produced nanoparticles have a spherical shape with an averaged diameter of Zn-Fe nanoparticles of 13 nm. FTIR and XRD test results of Zn-Fe nanoparticles show characteristics of Zn-Fe compounds. The examination of Zn-Fe nanoparticles as MRI contrast agents was carried out by varying the concentration of nanoparticles. Cenh calculation results showed the highest contrast enhancement occurred at a concentration of 1.25 mM with a value of 64.26% for T1 weighted images, and 81.52% for T2 weighted images. The SNR calculation results show the highest value at a concentration of 1.25 mM of 70.52 for T1 weighted images. The highest SNR value in the T2 weighted image at a concentration of 0.156 mM of 165.09.
Transduction matrix to enable sensor-less application of DC motor Tanra, Ivan; Ling, Shih-fu
Journal of Physics and Its Applications Vol 1, No 2 (2019): May 2019
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v1i2.4627

Abstract

Sensorless technology is one of the popular topic in motor industry. The aim is to reduce number of sensor and sensor size in the system. One of the method to achieve this sensor-less application of a motor is thru transduction matrix method. Transduction matrix is a 2x2 matrix that show the relationship between electrical input and mechanical output  of the motor. By obtaining the transduction matrix of a chosen motor, the mechanical output of the motor can be calculated from its electrical input. This paper explains the theory behind and the method to obtain the transduction matrix of a DC motor. The DC motor is chosen because it is the common motor in industry.
Generation of monocycle efficient terahertz pulses by optical rectification in LiNBO3 at 800 nm Khumaeni, Ali; Kitahara,, Hideaki; Furuya, Takashi; Yamamoto, Kohji; Tani, Masahiko
Journal of Physics and Its Applications Vol 1, No 1 (2018): November 2018
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v1i1.3912

Abstract

Generation of efficient terahertz (THz) pulses was experimentally made by tilted pump pulse front scheme with a Mg-doped LiNbO3 crystal. In this study, a spitfire laser (Ti:sapphire laser, 800 nm, 3 mJ, 1 kHz) was used as an optical source for the generation and detection of THz pulses. The electro-optic (EO) detection optics consisting of a ZnTe crystal (1 mm in thickness) and a balanced photodetector was used. To obtain optimum THz characteristics and pump to THz power conversion efficiency, the image of the grating was made coincides with the tilted pump pulse front. The maximum THz electric field of 8.5 kV/cm and the frequency bandwidth of 2.5 THz were achieved by using pump pulse energy of 2.4 mJ and pump pulse width of 100 fs. The THz energy of 4.15 μJ was obtained and pump-to-THz conversion efficiency was estimated to be approximately 1.73 x 10-3.
Some studies on Lorentz transformation matrix in non-cartesian co-ordinate system Das, Mukul Chandra; Misra, Rampada
Journal of Physics and Its Applications Vol 1, No 2 (2019): May 2019
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v1i2.4951

Abstract

The Lorentz matrices for transformation of co-ordinates in Cartesian system are presented for the cases when the relative velocity between two reference frames is along X , Y and Z axes. The general form of the matrix for transformation of co-ordinates from unprimed to primed frame has been deduced in case of Cartesian co-ordinate system with the help of the above matrices. This matrix has not been transformed to the cases of cylindrical and spherical polar co-ordinates due to the fact that the calculations are cumbersome and lengthy. Hence, considering the relative velocity between two frames along a co-ordinate axis the transformation matrix has been found out for cylindrical and spherical co-ordinates.
Electron contamination for 6 MV photon beams from an Elekta linac: Monte Carlo simulation Anam, Choirul; Soejoko, Djarwani S; Haryanto, Freddy; Yani, Sitti; Dougherty, Geoff
Journal of Physics and Its Applications Vol 2, No 2 (2020): May 2020
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v2i2.7771

Abstract

In external beam radiotherapy, the photons from a linear accelerator (linac) machine undergo multiple interactions, not only in the patient but also in the linac head and the air column between the linac head and the patient. Electrons are released from these interactions and contaminate the beams. The current study evaluates electron contamination for 6 MV photon beams from an Elekta linac using Monte Carlo simulation. The linac head was simulated by the BEAMnrc code and the absorbed dose in a phantom was calculated using the DOSXYZnrc code. The parameters of the initial electron beams on the target, such as mean energy and radial intensity distribution, were determined by matching the calculated dose distributions with the measured dose (at 10 x 10 cm2 field size and 90 cm source-skin distance). The central axis depth-dose curves of electron contamination were calculated for various field sizes from 5 x 5 cm2 to 40 x 40 cm2. We investigated the components that generated the electron contamination for a field size of 10 x 10 cm2. The optimal initial electron beam energy was 6.3 MeV with a full-width half maximum (FWHM) of the radial intensity distribution of 1.0 mm. These parameters were found to be in good agreement with the measured data. Electron contamination increased as the field size increased. At a depth of 1.0 mm and field sizes of 5 x 5, 10 x 10, 20 x 20, 30 x 30, and 40 x 40 cm2, the doses from electron contamination were 3.71, 5.19, 14.39, 18.97 and 20.89 %, respectively. Electron contamination decreased with increased depth. At a depth of 15 mm, the electron contamination was about 1 %. It was mainly generated in the air column between the linac head and the phantom (3.65 %), the mirror (0.99 %), and the flattening filter (0.59 %) (for the depth of 1.0 mm and the field size of 10 x 10 cm2).
Propagation loss on a Si-Slab Waveguide: Simulation revisited Tresna, Wildan Panji; Maruyama, Takeo
Journal of Physics and Its Applications Vol 2, No 1 (2019): November 2019
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v2i1.6421

Abstract

Slab waveguide is one of the simplest types of optical waveguide, the confinement factor is only determined by the thickness of one side so that the propagation of light passing through it will be confined in the material. The slab waveguide is built from Si as the core material and SiO2 as the substrate. The use of various optical waveguides is very dependent on the objectives to be achieved in its application, for it is very important to know the characteristics of each optical waveguide. In this paper the writer wants to know the characteristics of a slab waveguide, specifically with regard to propagation loss. The simulation results show that the propagation loss in the slab waveguide design that the authors propose is around 0.1dB / mm in TE mode conditions. The occurrence of propagation loss in the simulation is likely due to imperfections in determining the effective material index in the design of the slab waveguide.
Design of Automatic Bottle Filling Using Raspberry Pi Arifianto, Hadyan; Adi, Kusworo; Widodo, Catur Edi
Journal of Physics and Its Applications Vol 1, No 1 (2018): November 2018
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v1i1.3910

Abstract

Water consumption is very high, especially in urban areas. This means a good business opportunity for small and medium enterprises. Those enterprises, therefore, require an automatic and affordable device that can fill water into bottles. Raspberry Pi is the center of the control system in designing this automatic bottle filling device. This is because Raspberry Pi comes a with GPIO pin that is used as an input-output controller. GPIO pin receives signal input from switches and sensors that are then processed using Python programming language to drive an actuator and a solenoid valve. Subsequent hardware testing includes tests for water sensor, director motor, alternating motor, and solenoid valve. It is found that the water sensor works at a voltage of 4.18 V and that The DC motor works at 13.92 V. It is also found that the DC motor moves back and forth at 34.77 V when it is moving up, and at -34.77 V, when it is moving down. Meanwhile, the solenoid valve is found to work at 224.9 V. Therefore; it’s very possible to use Raspberry Pi as the center of a control system for an automatic bottle filling device.
Concurrent measurement of sample and reference waveforms in an optical-pump terahertz-probe system using a controlled optical diaphragm shutter Afalla, Jessica; Kitahara, Hideaki; Moriyasu, Takeshi; Tani, Masahiko
Journal of Physics and Its Applications Vol 1, No 2 (2019): May 2019
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v1i2.4659

Abstract

We present concurrent measurement of sample and reference terahertz waveforms for an optical-pump terahertz-probe spectrometer, using a controlled optical diaphragm shutter for the optical pump line. When waveforms are taken consecutively, laser power fluctuations and other experimental conditions can introduce spectral artefacts, thus a concurrent measurement is preferred. Instead of techniques based on double modulation, the use of the diaphragm shutter eliminates the need for a second lock-in amplifier and/or constricted alignment due to the use of a single chopper blade for modulating two signals, simultaneously. Drude fitting of the complex conductivity obtained for GaAs confirms that measurements obtained using our set-up agree with reported scattering times.
Comparative Results of Regional and Residual Anomalies with the Upward Continuation, Moving Average, and Polynomial Methods for Magnetic Data Indrawati, Luvera Deva Intan; indriana, rina dwi; Nurwidyanto, Irham
Journal of Physics and Its Applications Vol 2, No 2 (2020): May 2020
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v2i2.7673

Abstract

Geophysics programing of regional and residual anomaly separation on Magnetic data has been carried out with the results compared with the upward continuation method in the OasisMontaj software. Separation of anomalies with moving average and polynomial methods is processed using Matlab programming. The orders used in the polynomial method are first-order, second-order and third-order. Comparison is done by calculating the match value. The chosen matching method is autocorrelation. Correlation of residual magnetic anomalies resulting from upward continuation (Magpick) to moving averages, 1st-order polynomials, 2nd-order polynomials and 3rd-order polynomials. Correlation values obtained for the moving average method are 0.9604, first order polynomial 0.9072, 2nd order polynomial 0.9482 and third order polynomial 0.6057. The moving average and second order polynomial methods can be used as a substitute method if we do not use the upward continuation method.

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