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Carbon fibre reinforced polymer composites (CFRP) is one of the common materials used in machining by various manufacturing industries. The most persistent challenges during the machining, both concerning the consistency of machined surfaces and the properties of the material, are the difficulties such as fibre pull-out, delamination, and decomposition of the material matrix. This preliminary research highlights the laser machining of thick CFRP using a fibre laser of more than 1 kW. Laser machining experiments have been conducted to examine the ability of the fibre laser machine to cut thick CFRP through their high-quality laser beams. Based on the results, the study showed how the heat affected zone can be reduced when the higher cooling period is used. The effects of modulated beam mode include substantial reductions in HAZ compared with other experimental results. In all experimental attempts, substantial damage has occurred. The results are important in assessing the relationship between laser machining parameters and cutting results.

Dynamic gameplay, fast-paced and fast-changing gameplay, where angle shooting (top and bottom corner) has the best chance of a good goal, are the main aspects of handball. When it comes to the narrow-angle area, the goalkeeper has trouble blocked the goal. Therefore, this research discusses image processing to investigate the shooting precision performance analysis to detect the ball's accuracy at high speed. In the handball goal, the participants had to complete 50 successful shots at each of the four target locations. Computer vision will then be implemented through a camera to identify the ball, followed by determining the accuracy of the ball position of floating, net tangle and farthest or smallest using object detection as the accuracy marker. The model will be trained using Deep Learning (DL) models of YOLOv2, YOLOv3, and Faster R-CNN and the best precision models of ball detection accuracy were compared. It was found that the best performance of the accuracy of the classifier Faster R-CNN produces 99% for all ball positions.

Proportional–integral–derivative (PID) controller is one of the linear control methods of closed-loop irrigation control. Today, it is mostly used in the industry to regulate industrial process variables such as pressure, flow rate, temperature, heat, and others. In precision farming, the use of technologies such as sensors and PID controllers is popular nowadays. The technologies help the farmer fasten the fertilizer's mixing process before using it directly to the crop. However, not all farms afford to use high technology, and using low-cost mixing systems is one way to reduce their cost. Therefore, this research investigates the accuracy of fertilizer mixture using low-cost methods, compares the results, and proposes improvements to ensure a better fertilizer distribution for precision farming. Different parameter tuning will affect the mixing process of the fertilizer. A series of experiments will be conducted based on the PID control parameter, the concentration of the salt solution, and the initial amount of nutrients in the mixing tank. The salt solution will be used as an alternative for the fertilizer because it contains some similar composition ingredients that the EC sensor can detect. The experiment starts with a preliminary test to determine the temperature effect on reading where room temperature will be the best for the next experiment. The best PID parameter that is used is K_P= 130 and K_I= 60 to prevent the phenomenon of overshoot occur during the mixing process. Using the same PID parameter for the next experiment had also found out that the higher the concentration of the salt solution, the higher the chance occur the phenomenon of overshoot. The initial amount of nutrients inside the mixing tank does not affect much for the mixing process because the best parameter for the experiment we had found from the previous experiment is used. The results extracted from the experiment that shows the mixing process from a low-cost automated fertilizer mixing system.

Perilaku masyarakat dalam menerapkan protokol kesehatan sangat penting dalam menangani pandemi terutama selama masa-masa awal pandemi ketika belum tersedia pengobatan atau vaksinasi. Pada minggu pertama bulan Mei 2021 didapatkan bahwa tingkat kepatuhan penduduk DKI Jakarta terhadap perilaku memakai masker sebesar 77,25% dan menjaga jarak sebesar 73,27%. Kementerian Kesehatan telah mengeluarkan panduan pencegahan dan pengendalian COVID-19 di tempat kerja yang memuat tentang apa saja yang harus dilakukan oleh manajemen dan pekerja. Sebagai bahan evaluasi, rekognisi dan perencanaan kebijakan dan program penanganan Covid-19 di sektor perkantoran, diperlukan penelitian mengenai faktor risiko yang mempengaruhi perilaku pekerja perkantoran dalam penerapan protokol kesehatan pencegahan Covid-19.Penelitian menggunakan desain studi potong lintang/cross sectional dengan jumlah responden sebanyak 211 orang. Pengumpulan data dilakukan secara non-probability sampling melalui pengisian kuesioner daring kepada seluruh pekerja perkantoran.Secara umum, sebagian besar pekerja perkantoran memiliki perilaku kurang (64,93%) dalam menerapkan protokol kesehatan. Hasil penelitian menunjukkan hubungan yang tidak signifikan (p value > 0,05) antara persepsi kerentanan dan keparahan (p value 0,325), persepsi manfaat (p value 0,424), persepsi hambatan (p value 0,787) dan persepsi keyakinan diri (p value 0,255) serta cues to action (p value 0,606) pada responden dengan pengetahuan rendah terhadap perilaku individu yang kurang dalam menerapkan protokol kesehatan. Tempat kerja tetap harus memberikan pemahaman, edukasi, sosialisasi dan konseling kepada para pekerja untuk dapat meningkatkan persepsi pekerja akan manfaat melakukan perilaku pencegahan Covid-19.

Precision farming is a topic that is gaining attention due to its potential to increase efficiency and reduce labor workload in the agriculture industry. Automation using mobile robots is expected to revolutionize the industry. however, a few technical challenges remain. This research is a test of a low-cost position sensor for the application of position estimation of a mobile robot. The objective is to measure the error produced by an ultra-wideband position sensor and to develop a mobile robot system using the Robot Operating System (ROS). The error generated is analyzed based on the measurements taken in outdoor and indoor experiment environment settings. The Root Mean Squared error method was performed to evaluate the performance of the position sensor. The result of the experiment shows that the installation layout of the sensors and the surrounding environment affects the error generated. It is concluded that the low-cost sensor has sufficient reliability for use in the agriculture setting.

Assistive grouser is an alternative grouser purposed by previous researchers that were used to help wheel rover to improve its performance especially when traversing on unconsolidated soft sand inclination slope. When using a normal grouser (conventional grouser), as the wheel rotates, the grouser pushes the sand particles under the wheel upward and toward the back of the wheel, and causing the wheel to get stuck into the sand surface as the wheel starts digging the sand. But by attaching the assistive grouser, it helps to minimize the subsequence sinkage. Assistive grousers are able to adjust its angle of attack when penetrating into the sand slope surface. Assistive grouser produces horizontal traction force that is similar to the bulldozing movement concept. When assistive grouser moves, it enters and exits sand surface without moving a large amount of sand particles from below of the wheel toward the back of the wheel and prevent the wheel from the stuck phase. From the previous experiment, by using assistive grouser with adjustable angle, it helps to improve the performance of wheel rover in term of minimizing the sand movement from under the wheel when the wheel rotates, less sinkage, and less current consumed during the movement of the wheel. However, during the experiment, the interaction between the assistive grouser and the sand cannot be seen clearly. The purpose of this study is to investigate and observe the interaction between assistive grouser (with varying angle of attack) and the sand particles especially on sand surface inclination slope by using computer simulation-Discrete Element Method (DEM) simulation at high slip condition. From the simulation, the effect of adjustable assistive grouser angle toward the traction force generated when the grouser and sand interact was observed. The highest normal force generated by using adjustable assistive grouser with 30-degree angle is around 900 N while the highest normal force generated by assistive grouser 0-degree angle is around 450 N. Assistive grouser that have same angle with the sand surface slope produced higher normal force and lead to produce higher traction force. The traction force helps the rover to climb the surface slope and move forward. And by using assistive grouser 30-degree, the area of destructive area is 230 cm2 which is bigger compared to assistive grouser 0-degree with 161 cm2. Destructive area portrays the relation between the grouser-sand and sand-sand particles.