The attandance of student in the classroom is reflecting their academic performance, the Department of Informatics Engineering in the Universitas Sebelas Maret used a manual way to record student attendance. The manual way is using papers to record student attendance and lecture activities, it may suffer to human error, because attandee can manipulate their presence and the departments can’t monitor them. Radio Frequency Identification (RFID) can be applied to identify various things, because it has unique information codes saved in a special chip called tags. RFID can be applied to developed an attendance system prototype. The term of Internet of Things (IoT) can be described as an embedded system with internet data exchange, by using this technology we can monitored and controlled the devices, also we can integrate the database. The aim of this research is to measure the data speed of the prototype of RFID attendance system, the prototype has function to stored, process, and record the student attendance in the Department of Informatics Engineering.

This study aimed to analyze the antibacterial activity of red galangal extract (Alpinia purpurata) against the growth of E. tarda. This aims of this study was to determine the antibacterial compounds and the antibacterial effectiveness of red galangal extract (A. purpurata) against the growth of E. tarda bacteria. Antibacterial activity test was carried out by MIC test and disc test. The MIC test used doses of 1 ppm, 10 ppm, 100 ppm, 500 ppm, and 1000 ppm with incubation for 24 hours. The disc test used doses of 100 ppm, 200 ppm, 300 ppm, 400 ppm, 500 ppm and a positive control of 5 ppm chloramphenicol and a negative control without treatment. Photochemical test of red galangal extract (A. purpurata) contains flavonoid compounds, alkaloids, tannins, triterpenoids, and saponins. The results of the disc test showed that the highest inhibitory diameter was 7.55 mm at a dose of 500 ppm and was bacteriostatic because it decreased its inhibitory zone after 48 hours of incubation. The highest inhibitory effectiveness was 56.56% at a dose of 500 ppm after 24 hours of incubation.

Barriers to cultivation activities are disease attacks, one of which is caused by infection with the bacterium Edwardsiella tarda. Treatment efforts can be made using natural ingredients such as jackfruit (A. heterophyllus) leaves. This study aims to determine the content of antibacterial compounds in the jackfruit (A. heterophyllus) leaves crude extract and their effect on Edwardsiella tarda bacteria in vitro. The inhibition test used disc test with five different concentrations of jackfruit (A. heterophyllus) leaves crude extract with three replications: 75 mg/L, 150 mg/L, 225 mg/L, 300 mg/L and 375 mg/L with a comparison using two types of controls (positive with 5 mg/L chloramphenicol antibiotics and negative with no treatment) using Tryptone Soy Agar (TSA) media and incubated for 2x24 hours. The results of phytochemical screening proved that the jackfruit (A. heterophyllus) leaves crude extract contains flavonoids, alkaloids, tannins and saponins. Treatment E with a dose of 375 mg/L gave the highest inhibition of 7.80 mm and treatment A with a dose of 75 mg/L gave the lowest inhibition of 4.38 mm.  The relationship between the treatment given to the test parameter in the form of the resulting inhibitory power obtained the equation y = 0.0111x + 3.6297 with an R2 value of 0.974 which means 97% of the treatment given in the form of crude extract of jackfruit (A. heterophyllus) leaves affects inhibition of bacteria E. tarda.