Claim Missing Document
Check
Articles

Found 2 Documents
Search

Rancang Bangun Alat Ukur Konsentrasi Logam Berat Timbal Berbasis Sensor Serat Optik Evanescent dengan Cladding Kitosan Rahayu, Aida; Harmadi, Harmadi
Jurnal Fisika Unand Vol 9 No 1 (2020)
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jfu.9.1.17-23.2020

Abstract

Telah dirancang alat ukur konsentrasi ion logam berat timbal berbasis sensor serat optik evanescent. Cladding serat optik dikupas dan diganti dengan kitosan. Variasi panjang pengupasan cladding serat optik adalah 1 cm, 2 cm, dan 3 cm. Sistem sensor terdiri dari laser dioda sebagai sumber cahaya, serat optik, fotodioda sebagai detektor cahaya, mikrokontroler sebagai pengolah sinyal dan LCD sebagai penampil hasil pengukuran. Konsentrasi diukur berdasarkan tegangan keluaran fotodioda. Semakin tinggi konsentrasi maka semakin tinggi tegangan keluaran fotodioda. Hasil karakterisasi serat optik menunjukkan serat optik dengan panjang pengupasan 1 cm, dan jari-jari bending 3,5 cm adalah yang paling optimal untuk pengukuran konsentrasi ion logam berat timbal dengan koefisien korelasi 0,9906. Persentase rata-rata kesalahan alat ukur yang dirancang adalah 43,334%. It has been designed for optical fiber sensor-based lead ion heavy metal measuring devices. Optical fiber cladding is peeled and replaced with chitosan. Variations in stripping length of optical fiber cladding are 1 cm, 2 cm, and 3 cm. The sensor system consists of a laser diode as a light source, fiber optic, photodiode as a light detector, a microcontroller as a signal processor and an LCD as a measurement result viewer. The concentration released is based on the photodiode output voltage. The higher the concentration, the higher the photodiode output voltage. The result of optical fiber characterization that shows optical fibers with stripping length of 1 cm and bending radius of 3.5 cm are the most optimal for measuring the concentration of lead heavy metals with a coefficient of 0.9906. The average percentage of errors of the measuring instruments designed is 43.334%.
Perbandingan Metode Continuous Review dan Periodic Review Dalam Pengendalian Persediaan Bahan Baku (studi kasus: UD. Keripik Cinta Mas Hendro) Rahayu, Aida; Manurung, Asima
Leibniz: Jurnal Matematika Vol. 4 No. 2 (2024): Leibniz: Jurnal Matematika
Publisher : Program Studi Matematika - Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas San Pedro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.59632/leibniz.v4i02.444

Abstract

UD. Keripik Cinta Mas Hendro is a business that produces snacks, the most popular product is cassava chips, with poor policies it is very risky for consumer demand and costs incurred in cassava inventory. This study aims to optimize the total inventory cost and obtain the right method in inventory control using Continuous Review and Periodic Review. The calculation results show that Continuous Review is the right method with a minimum cost of Rp 3,305,310,721 with a savings percentage of 4.70% and has an order size of q = 230,121.99 kg, and a reorder point r = 9,967.13 kg.