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Designing microstrip antennas with wide bandwidth and low-frequency capabilities presents several challenges. These difficulties mainly arise due to the relatively small size of the microstrip in comparison to the operating frequency. Therefore, achieving a combination of enhanced bandwidth and lowerfrequency cut-off becomes crucial to support a broad frequency range of communication technologies. This paper presents a method for enhancing the bandwidth of a circular microstrip antenna based on an inverted C-shaped ground configuration. The proposed method successfully creates an antenna with extended bandwidth while lowering the operating frequency. The antenna was simulated and then fabricated using an RO5880 duroid substrate with a relative permittivity of 2.2, a thickness of 1.575 mm, and a loss tangent of 0.0009. The simulation and measurement results demonstrate that the antenna can operate effectively within a wide frequency range of 3.5 GHz to 18 GHz. Additionally, utilizing this method enables the antenna to function at even lower frequencies and wider bandwidth without the need for additional dimensions.

Road crack detection is critical to road infrastructure maintenance, requiring sophisticated and accurate approaches. This research explores the utilization of a combination of Wavelet and Convolutional Neural Network (CNN) methods to improve efficiency and accuracy in detecting cracks in road images. The wavelet method was chosen for its capability to capture information at different scales, enabling improved feature extraction. Meanwhile, CNN was utilized to comprehend the spatial context and tackle image complexity. The research involves several stages, including data collection, pre-processing, decomposition using the Wavelet method, forming of the CNN architecture model, training, testing, and evaluating the result. The tested images involve three main types of cracks: alligator, linear, and images without cracks. The testing results show that the developed model is capable of classifying cracks with an F1-score of 0.96, recall of 0.96, and precision of 0.96. In real-time detection of road cracks, the testing obtained an F1-score of 0.84, recall of 0.92, and precision of 0.77. This research contributes to the advancement of road crack detection technology by leveraging the capabilities of Wavelet and CNN, enhancing the accuracy and efficiency of crack detection in road maintenance.

This paper proposes dual functional microwave sensor for displacement and angular detection of liquid material based on electric coupled (ELC) resonator. The proposed resonator uses a two-port band stop filter operating at a resonant frequency of 2.72 GHz. Polystyrene-mm pipe channels are used to accommodate water samples placed in the sensing area of the sensor in the center of the ELC resonator. Displacement and angular detection were observed based on the shift in the resonant frequency of the resonator. Based on the measurement results, the proposed sensor has a sensitivity for displacement detection of 31.5 MHz/cm with a distance range of d =1 – 4 cm while for angular detection it is 0.33 MHz/o with a rotation angle of 0 – 90° for polystyrene-mm pipe channel filled with water content. This paper makes a significant contribution by proposed a dual functional microwave sensor for displacement and angular detection that can be recommended for the automotive, robotics and aerospace industries.

The SIW antenna suffers from the narrow bandwidth for a single cavity and single resonant. Defected ground structure (DGS) with a dual cavity was the solution to solve narrow bandwidth by resulting in hybrid resonance. The hybrid resonance with 14.83% impedance bandwidth is proposed in this antenna design. The first resonance resulted from the combination of the TE101 modes from inner and outer HMSIW cavities while the second resonance resulted from the combination of the strong TE101 and the weak TE102 mode from the inner HMSIW cavity and the addition of the weak TE101 from the outer HMSIW cavity. The measurement antenna design has a broadband antenna with a 14.31% (5.71 – 6.59 GHz) impedance bandwidth by using substrate Rogers RO 5880.

A band-pass filter (BPF) is an essential part of a wireless communication system as it functions to reduce interference and noise. Many structures have been proposed to achieve a high-quality BPF. Typically, these structures utilize vias. However, vias has several drawbacks, including impedance discontinuities, increased resistance values, and complex structures. In this study, we propose a dual-band BPF based on a cascaded closed ring resonator (CCRR) without using vias. Specifically, the proposed structure consists of multiple CCRRs connected at the corner pattern and incorporates capacitive coupling to the input impedance. Additionally, the CCRR configuration has dual sizing to achieve dual-band performance. Subsequently, the proposed BPF is simulated and fabricated using Duroid Rogers RT 5880 with dielectric constant εr = 2.2, dissipation factor tan δ = 0.0009, and thickness h = 1.575 mm. The measurement results demonstrated that the dual-band BPF operated at a resonant frequency of 2.50 GHz with a transmission coefficient (S21) value of -2.18 dB in the first band. In the second band, a resonant frequency of 3.70 GHz was obtained with an S21 value of -1.43 dB. The bandwidth in the first band was 160 MHz, and in the second band, it was 110 MHz. Moreover, based on the measurement results, the reflection coefficient (S11) in the first band was -11.05 dB, while in the second band, it was -23.3 dB. The excellent agreement between the simulation and measurement validates the proposed method.

ABSTRAK Makalah ini mengusulkan antena mikrostrip dengan dengan performansi tinggi yang beroperasi pada frekuensi resonansi 3,5 GHz untuk sistem komunikasi 5G. Antena dikembangkan dalam dengan teknik array planar seri 4x2 elemen yang dikonfigurasi MIMO. Berdasarkan hasil pengukuran, antena yang dirancang memiliki koefisien refleksi

Gold nanoparticles film as a part of an optical sensor is considered as active support in the development of specific chemical or biological biosensors optically. Well-organized gold nanoparticles can be prepared through inexpensive approaches where gold nanoparticles are easily obtained on a glass substrate. Herein, the authors propose a low-cost thermal synthesis of active plasmonic nanostructures on thin gold layers modified by a short annealing time (1 min and 15 min) at 550 °C and quickly followed by simple quenching. The results proved a good reproducibility of localized surface plasmon resonance (LSPR) optical responses with investigate the effects of modified thermal treatment on the morphology of gold thin films, the extinction LSPR spectra characteristics in the range between 350−1000 nm, and the quality factor (Q-factor) of the plasmonic resonance. The present findings that the proposed method gives evidence enhancement with the enrichment factor (EF-factor) values by about 310 %–460 %. We believe our study may have provided a strategy to enhance the fabrication of gold nanoparticles film based on plasmonic nanostructures for LSPR chip sensor applications.

EFFECT OF Al, Zr AND Mo ON CORROSION RESISTANCE OF AlXCrFeNiMo AND AlXCrFeNiZr (X=1, 1.2 AND 1.4) AS FUEL CLADDING MATERIALS. The high entropy alloy of AlxCrFeNiM (with x = 1, 1,2 and 1,4; M = Mo and Zr) was successfully synthesized using powder metallurgy technique with sintering process at 1000 oC in an inert atmosphere. These alloys were designated as fuel cladding for research reactor with high U-density fuel such as U-Mo. One of the critical in-service properties of nuclear fuel cladding is its corrosion behavior. In this study, some properties of the HEA of AlxCrFeNiM such as the phases, microstructures, hardness, and corrosion resistance in 3 wt.% NaCl solution at room temperature were investigated. The results show that the phases in the HEA of AlxCrFeNiMo are FeNi, AlNi and Mo. The HEA of AlxCrFeNiZr has more complex phases compared to the AlxCrFeNiMo. The microstructure of HEA samples show fine grains with some micropores that imperfect the solidification during the sintering process. The hardness value of the HEA of AlxCrFeNiMo has a trend of decreasing as the x value increases. The opposite trend occurs to the HEA of AlxCrFeNiZr that the hardness value increases with increasing x value. The lowest hardness value is Al1.4CrFeNiMo at 262.2 HV, and the highest hardness value of Al1.4CrFeNiZr is at 756.7 HV. The corrosion rate of the AlxCrFeNiMo does not show a specific trend with increasing x value; however, the AlxCrFeNiZr shows decreasing value with increasing x value. The lowest value for the all-HEA samples is 0.20 mmpy for the Al1.4CrFeNiZr. The results of hardness and corrosion tests show that the Zr element combined with the Al element affects not only its hardness but also its corrosion resistance. Keywords: Fuel cladding, high entropy alloy, corrosion.

ABSTRAK Jalan kelas IIIC memiliki struktur yang lebih sempit dan biasanya dibangun didekat permukiman penduduk untuk penggunaan pejalan kaki. Selain pejalan kaki, kendaraan motor roda dua juga dapat mempergunakaan jalan tersebut. Permasalahan mulai timbul saat kendaaraan bermotor memiliki kecepatan yang cukup tinggi sehingga membahayakan pengguna jalan lainnya khususnya pedestrian. Untuk mengatasi hal tersebut, pada penelitian ini dilakukan pengembangan X-band speed detector berbasis efek pergeseran doppler untuk kendaraan motor roda dua di jalan kelas IIIC. Detektor yang dibangun mengimplementasikan sensor HB100 dengan frekuensi 10 GHz Adapun efek pergeseran doppler diproses menggunakan Arduino. Parameter yang dijadikan perhitungan diantaranya kecepatan, pergeseran doppler, dan jarak detektor. Hasil pengujian menunjukan bahwa sistem berhasil memiliki akurasi diatas 95% (atau error

This study carried out on the effect of precursor concentration and annealed substrate temperature on the crystal structure, electronic and optical properties of ZnO thin film. An aqueous solution of Acid Nitrite was used as precursors and its concentration was varied from 0.1 M to 0.4 M. The ZnO thin film was deposited on the glass substrate by Spray Pyrolysis Deposition and annealed with different temperature from 300 oC to 600 oC. The crystal structure, electronic and optical properties were investigated by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and UV-Spectrometer. XRD result showed that all thin films have amorphous hexagonal wurtzite crystalline. Particle sizes ranging from 21.83 to 43.67 nm were calculated through Debye-Scherer Method. It showed that the concentration of the precursor had slightly impact on the particle size. Meanwhile, the increase in particle size with increasing annealed temperature is found to be gradual. The average transparent of all thin film was more than 80%. The bandgap of the ZnO thin films was estimated by Tauc Plot Relation. It showed that the bandgap values were increased with the increasing of precursor concentration due to Burstein-Moss Effect. In addition, the decrease in band gap values was found with increasing annealed temperature. Our results demonstrated that the varying precursor concentration and annealed substrate temperature can enhance the structure, electronic and the optical properties of ZnO thin films.

The main problem in designing a multiband bandpass filter (BPF) is making each passband response highly independent, where each bandwidth of multiband BPF can be controlled and adjusted separately. To overcome this problem, this paper proposes a highly independent multiband BPF based on a multicoupled line stub-SIR with a folding structure. The proposed multiband BPF is constructed as a multicoupled line to generate a highly independent inter-passband. Moreover, the multiband performance is produced separately and independently by using three sets of resonators: resonator A1/A2 (RA1 and RA2), resonator B1/B2 (RB1 and RB2), and resonator C1/C2 (RC1 and RC2). The three passband frequencies can be independently arranged and designed. To miniaturize the multiband BPF, a folding structure is also proposed. As a result, the multiband BPF has a compact size that is reduced by over 61.29 % compared to previous structures. The even-odd excitation model and the equivalent circuit model are used to analyze the multiband BPF structure. This BPF is designed for GPS applications at 1.57 GHz, WCDMA (3G) at 1.8 GHz, WLAN (WiFi) at 2.4 GHz, LTE (4G) at 2.6 GHz, and 5G communication at 3.5 GHz. To evaluate and validate the proposed structure of the multiband BPF, the circuits are fabricated and tested. The simulated and measured results of the multiband BPF show good agreement. In conclusion, the proposed multiband BPF structure has a highly independent inter passband response and a compact size.

In conventional hybrid reversible data hiding in encrypted images (RDHEI), the error-free extracted-bit rate condition in recovered images cannot be fully achieved (reversible) as the block size decreases because of the fluctuation function used, which cannot reduce the bit error, as indicated by the high extracted-bit error rate (EER) and low peak signal-to-noise ratio (PSNR). Therefore, this work proposes improving the accuracy of hybrid RDHEI performance for remote sensing satellite images by modifying the fluctuation function in the data extraction process with and without the Reed-Solomon (RS) codes in the data embedding process. The proposed fluctuation function takes the absolute difference in the actual value of two adjacent pixels in horizontal and vertical pixels. The modified fluctuation function algorithm in the extraction process both with and without RS codes in the embedding data process is derived, and performance results are obtained through simulations of SPOT-6, SPOT-7, and Pleiades-1A satellite images. The simulation results show that the proposed hybrid RDHEI algorithm with modification of the fluctuation function without an RS encoder can achieve error-free extracted-bit and maximum PSNR (infinity) values at a block size of 18 × 18 for SPOT-6 and SPOT-7 test images, as well as a block size of 20 × 20 for the Pleiades-1A test image. It is proven that the proposed hybrid RDHEI succeeds in reducing the minimum block size from reference systems. In addition, it can also be seen that the proposed hybrid RDHEI with modification of the fluctuation function and RS coding in data embedding can reduce the minimum block size to achieve error-free extracted bits to 9 × 9 for SPOT-6 and SPOT-7 test images and 10 × 10 for the Pleiades-1A test image.

Neighbour Discovery Protocol is a core IPv6 protocol used within the local network to provide functionalities such as Router Discovery and Neighbour Discovery. However, the standard of the protocol does not specify any security mechanism but only recommends the use of either Internet Protocol Security (IPSec) or Secure Neighbor Discovery (SEND) that has drawbacks when used within IPv6 local network. Furthermore, neither is enabled by default in the IPv6 local network; leaving the protocol unsecured. This paper proposes Trust-ND with reduced complexity by combining hard security and soft security approaches to be implemented on securing IPv6 link-local communication. The experimentation results showed that Trust-ND managed to successfully secure the IPv6 Neighbour Discovery. Trust-ND significantly cuts down the time to process NDP messages up to 77.21 ms for solicitation message and 100.732 ms for advertisement message. It also provides additional benefit over regular NDP in terms of data integrity for all Trust-ND messages with the introduction of Trust Option.

Untuk mendeteksi tingkat osteoporosis biasanya dipergunakan perangkat Dual Energi X-Ray Absorptiometri (DEXA). Akan tetapi, karena harga dan biaya operasionalnya yang tinggi, maka perangkat DEXA sangat jarang dipergunakan. Untuk memberikan solusi tersebut maka pada penelitian ini dilakukan kuantisasi data dengan bantuan aplikasi perangkat lunak komputer, yang berupa algoritma pengolahan citra digital untuk meningkatkan kualitas citra (Image Enhacement), konvolusi dua dimensi, penghalusan, dan penajaman citra, serta deteksi tepian pada trabekula sinar x-ray vertebra spinal. Hasil dari penelitian ini menunjukkan metode Index Singh pada citra x-ray vertebra spinalis dapat digunakan untuk pengurutan dan pengelompokkan pixel putih dalam deteksi tingkat osteoporosis. Jumlah pixel putih pada perhitungan berdasarkan luas kolom dan baris area merupakan dari jumlah keraptan atau kepadatan dari massa tulang vertebra spinalis. Dari 50 sempel uji citra x-ray pixel putih tertinggi adalah 7.983 pixel dan pixel putih terendah adalah 5.410 pixel.

A multiwideband bandpass filter (MW-BPF) using a quad cross-stub stepped impedance resonator (QC-SSIR) was simulated, fabricated, and measured. The proposed QC-SSIR is designed on a four-series arrangement of crossed open stub (COS) structures where each open stub is developed with a step impedance resonator (SIR) structure to generate a wide bandwidth. Compared to the COS resonator, the QC-SSIR has a wider fractional bandwidth and good transmission coefficients and is compact. ABCD matrix analysis is used to investigate the filter structure. Furthermore, the MW-BPF is designed on an FR4 microstrip substrate with εr = 4.4, thickness h = 1.6 mm, and tan δ = 0.0265. The results show that the proposed MW-BPF using a QC-SSIR achieves transmission coefficients/fractional bandwidths of −0.60 dB/49.3%, −1.49 dB/18.7%, and −1.93 dB/13.9% at 0.81 GHz, 1.71 GHz, and 2.58 GHz, respectively. Furthermore, to reduce the filter size, a folded QC-SSIR (FQC-SSIR) structure was also proposed. The results show that the proposed MW-BPF using an FQC-SSIR achieves transmission coefficients/fractional bandwidths of −0.57 dB/49.6%, −1.21 dB/17.7%, and −1.76 dB/12.5% at 0.82 GHz, 1.80 GHz, and 2.62 GHz, respectively. The size of the proposed MW-BPF using an FQC-SSIR is reduced by up to 46% compared with the MW-BPF using a QC-SSIR. Finally, the performance of the simulated MW-BPF based on the QC-SSIR and FQC-SSIR was in good agreement with the measurement results.

In telecommunications equipment, an oscillator has a function to generate a carrier signal. As the carrier signal, a high stability performance is required. The frequency shift caused by component tolerances. In this research, a Monte-Carlo method was used to analyze a component tolerance on the performance of the oscillator at a frequency 2.3 GHz. A simulation was performed by software Advance Design System (ADS). In this research, the iterations were carried out as many as 212 times with tolerance component values by 10%. The analyzed performance consists of a fundamental frequency shift, a phase noise, the value of power fundamental, and a harmonic power. Meanwhile, the oscillator has a structure of bias BJT common base-bias BFR183 with Vcc = 20 V, Vce = 8.2 V and Ic = 15 mA and a dielectric resonator as a resonator. The oscillator has a fundamental frequency 2.3 GHz, phase noise -135.6 dBc / Hz, power fundamental 10.8 dBm, and harmonic power -11.2 dBm. The simulation results showed that the oscillator has a good performance with a high degree of stability on a fundamental frequency by 73%, stability phase noise 100%, stability power fundamental 64%, and stability harmonic power 61%. This simulation has a confidence level of 95.4%, an error ± 3%, and the estimation accuracy 95%.

In this research, a triple-band bandpass filter (BPF) using a cascade tri section step impedance resonator (TSSIR), which can be operated at 900 MHz, 1,800 MHz, and 2,600 MHz simultaneously, was designed, fabricated and evaluated. Advanced Design System (ADS) was used to design and simulate the proposed BPF. The proposed BPF using cascade TSSIR was fabricated on an FR4 substrate with dielectric permittivity, substrate thickness and loss tangent at 4.3, 1.6 mm and 0.0017, respectively. The performance parameters of the proposed BPF were characterized by insertion loss, return loss, voltage standing wave ratio (VSWR) and group delay. The performance results from the simulation were compared to those of the fabricated BPF. The results showed that the performances from both the simulated and the fabricated BPF satisfied the design specifications and were in close agreement with each other. Furthermore, the results indicated that the proposed BPF using cascade TSSIR performed better than a hairpin BPF with TSSIR.

In this study, It is proposed a design of electric surgery on 10 KHz. This device consists of a power supply circuit, a voltage regulator, and a frequency counter. The purpose of this study is expected to minimize the occurrence of spark overs and the occurrence of burns. The measurement results show that LPES is working with a power of 26 watts and a frequency of 11.16 KHz. Electric surgery was tested against buffalo meat, mutton and beef. In beef by applying a voltage of 28.7 volts takes 51 seconds, using a voltage of 28.1 volts takes 53 seconds, using a voltage of 27.8 volts takes 57 seconds. In goat meat by using a voltage of 28.7 volts takes 30 seconds, using a voltage of 28.1 volts takes 41 seconds, using a voltage of 27.8 volts takes 49 seconds. In buffalo meat by using a voltage of 28.7 volts takes 52 seconds, using a voltage of 28.1 volts takes 56 seconds, using a voltage of 27.8 volts takes 59 seconds. Compare to another electric surgery, this study had low power and low frequency, so as to minimize the occurrence of spark over with good speed cutting process.

The main problem of intensity modulation (IM) in radio-over-fiber (RoF) communication is dispersion power fading (DPF), which occurs when the signal is transmitted through a dispersive link that causes a sideband cancelation effect. The DPF level of the RoF link is determined by the deviation factor (DF). The optical single-sideband (OSSB) modulation scheme, which is generated by driving one of the dual-drive Mach–Zehnder modulators (DD-MZMs), is usually used to overcome DPF. The DF value of OSSB modulation at modulation index m = 0.1 increases from 0.008 to 0.930 at m = 1. It can be said that this method is only effective at reducing DF at low m. However, as well-known information of the DD-MZM system, high-efficiency optic–electric conversions can be obtained at high m values, but DF will increase. Therefore, reducing the DPF value for high m ≥ 0.1 is interesting. It is known that in wireless communication, to reduce the impact of fading, direct signals are amplified and signals with irregular phases are used. Moreover, this paper proposes the DD-MZM with an asymmetric carrier divider as a direct signal and combines it with an irregular radio frequency (RF) phase to reduce the DPF at high m. The carrier that is generated by laser diode (LD) power (PIN) is divided asymmetrically as power modulation (PDD-MZM) and carrier arm (CA) power (PCA). Furthermore, the minimum DF is obtained when the PIN is separated as 75% for PCA and 25% for PDD-MZM with an irregular RF signal of θ = 48° and a bias point value of γ = ¾. As a result, with the same power as OSSB, this proposed structure produces DF at m = 0.1 and m = 1 with values of 0.008 and 0.03, or it can reduce DF of 96.7% at m = 1. The mathematical model and simulation model have very good agreement, which validates the proposed method.

The main problem with the radio-over-fiber (RoF) link is the decrease in the recovered radio frequency (RF) power due to the chromatic dispersion of the fiber known as dispersion power fading. One of the methods for dealing with dispersion power fading is to use the optical single sideband (OSSB) modulation scheme. The OSSB modulation scheme can be generated by biasing the dual-drive Mach−Zehnder modulator (DD-MZM) to the quadrature bias point (QBP) and shifting the RF drive signal phase (θ) by 90°, which is called the regular θ. However, the OSSB modulation scheme only overcomes dispersion power fading well at the modulation index (m) < 0.2. This paper proposes an irregular θ method to overcome dispersion power fading at all m. There are two irregular θ for every m used. The irregular θ managed to handle dispersion power fading better than OSSB modulation scheme did at every m. Specifically, the irregular θ could handle the dispersion power fading well at m ≤ 1. In sum, the irregular θ could overcome the dispersion power fading at any RF frequency and optical wavelength without having to re-adjust the transmitter.

A compact multiband bandpass filter (BPF) based on folded dual crossed open stubs (DCOS) is designed and analyzed. Two Crossed Open Stubs (COS) are used to generate concurrent six-band BPF, where the center frequency located at 0.95 GHz, 1.85 GHz, 2.65 GHz, 3.35 GHz, 4.375 GHz, and 5.25 GHz. The proposed BPF based on folded Dual Crossed Open Stubs (DCOS) is an expansion of tri-band BPF based on a single COS, where the second COS is used to generate second additional tri-band. To achieve miniaturization structure of proposed BPF, the DCOS is folded. The proposed BPF will be designed and analyzed by using Advanced System Design (ADS). The performances of multiband BPF which characterized by return loss, insertion loss, voltage standing wave ratio (VSWR), and group delay, are conducted by simulation, measurement and analysis. It is shown that the simulation and fabrication results of insertion loss, return loss, VSWR, and group delay of the proposed multiband BPF are satisfied to design requirements. However, the center frequencies of fabricated the proposed multiband BPF are shifted average to 5?30 MHz lead to simulated results. This is due to some errors in fabricated process including imperfect dimension of fabricated BPF, soldering between connector to substrate and cable losses.