<p class="JIPIAbstractBody">Telah berhasil diciptakan alat monitoring denyut jantung, saturasi oksigen (SpO₂) dalam darah, dan suhu tubuh penderita COVID-19 berbasis IoT. Alat ini berupa gelang yang mana terdiri dari beberapa alat penting, yaitu NodeMCU ESP8266, TCA9548A, lcd oled 128 x 64 pixel, sensor AD8232, sensor MAX30100, dan sensorMPU6050. Alat ini ditujukan untuk penanganan penderita COVID-19 di Indonesia khususnya pasien rawat inap yang berada di rumah sakit darurat ataupun rumah sakit rujukan COVID-19. Metode analisis yang digunakan dalam penelitian ini adalah metode perbandingan, yaitu dengan membandingkan hasil ukur alat yang dibuat dengan alat ukur yang telah ada, seperti oximeter dan thermometer klinis. Hasil ukur denyut jantung menunjukan error yang besar, yaitu sebesar  4,12%, sedangkan hasil ukur saturasi oksigen dan suhu tubuh memiliki error relatif kecil, yaitu sebesar 1,27% dan 0,35%. Hasil pengukuran dapat dilihat pada website Thingspeak.com dalam bentuk grafik. Pengiriman data  dengan kecepatan internet 1,27 Mbps alat berhasil mengirimkan 16 dari 220 data dengan jeda 16-60 detik. Peletakan sensor denyut jantung yang tidak tepat memberikan error yang cukup besar.</p>

The good physical and chemical properties of metal ferrite nanoparticles can be used as potential materials when applied. This study aims to explore the physical and chemical properties, such as phase, structure, morphology, and vibration of Ni-Zn-Co ferrites nanoparticles annealed at different temperatures. Ni0.4Zn0.5Co0.1Fe2O4 nanoparticles were synthesized by coprecipitation method and characterized by X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), and Fourier Transform Infrared (FTIR) Spectroscopy to determine their structure, morphology, and vibration. Overall, all samples showed spinel cubic structures. In addition, XRD analysis showed the phase transformation from magnetite to hematite by increasing the temperature. The increase of annealing temperature leads to the larger average size of nanoparticles which were estimated by analyzing TEM images. The average diameter of nanoparticles with annealing temperature of 600°C was (10.9 + 0.5) nm and the average diameter of nanoparticles with annealing temperature of 1000°C was (18.6 + 4) nm. FTIR measurements between (4000 – 400) cm-1 confirmed the absorption band in the spectrum. The FTIR spectra of the nanoparticles confirmed the presence of metal ion vibrational bands located at octahedral and tetrahedral sites in 418 cm-1 to 696 cm-1. This implies that Ni-Zn-Co ferrites has truly the spinel cubic structures considering their absorption characteristics at about (500 – 600) cm-1.