Judul: Noise Analysis of Biodiesel Plant P3 Machinery Production to The Operator Performance at PT SMART Tbk., Marunda, Jawa Barat
Abstrak: Noise is one of the essential aspects in ergonomics. This study aims to analyze the distribution pattern of noise in the biodiesel production factory room, evaluate the magnitude of noise received by the hearing sense of the operators of the biodiesel Plant P3 production machine, and determine the appropriate Noise Risk Assessment based on the analysis. PT SMART Tbk. has a biodiesel Plant P3 factory that operates 24 hours, and the use of various machines results in a significant level of noise. The measurement results indicate that the noise levels on floors 1 through 4 are below the threshold value. However, the noise level on the 5th floor exceeds 85 dB, which means that workers can work without maximum protective equipment for only 57 - 64.2 minutes. Therefore, it is necessary to control the noise by reducing the noise on the 5th floor to avoid compromising the health and comfort of the workers. The use of personal protective equipment is also essential to mitigate the negative impact of noise exposure on the workers in the factory environment.
Keyword: Ergonomics, Noise, Biodiesel Production, Threshold Limit Value, Noise Risk Assessment

Judul: Analysis of noise and mechanical vibration in power house oil palm plant PT Condong, Garut, West Java
Abstrak: Power house merupakan stasiun penyedia sumber listrik utama pabrik yang dihasilkan dari generator dan mesin uap. Tujuan dari penelitian ini adalah menganalisis tingkat dan pola sebaran kebisingan dan getaran mekanis, menentukan durasi aman maksimum pada area kerja, dan memberikan rekomendasi untuk mengatasi masalah kebisingan dan getaran mekanis tersebut. Pengukuran dilakukan dengan metode grid dan pemetaan pola kebisingan dan getaran dilakukan sesuai dengan kaidah kontur. Hasil pengukuran kebisingan menunjukkan intensitas kebisingan pada power house berkisar 83.36–97.32 dB(A) dan intensitas percepatan getaran maksimum yang merambat ke lantai berkisar 0 sampai 0.3 m/s[2]. Berdasarkan analisis data pengukuran, dapat disimpulkan bahwa daerah power house merupakan daerah dengan tingkat kebisingan yang tinggi. Durasi aman bekerja di dalam power house adalah 3 jam per hari. Oleh karena itu, pekerja disarankan untuk menggunakan pelindung telinga agar bisa bekerja di dalam power house selama 8 jam kerja per hari.
Keyword: power house, mechanical vibration, noise

Judul: Pelabelan Super Vertex Magic
Abstrak: Super vertex magic labeling is labeling on graph with is a set of edges mapped into and is a set of vertices mapped into . It has a vertex magic labeling in which and represents the size and order of the graph respectively. This manuscript proves that paths, cyclics, and disjoint union of cyclics have a super vertex magic labeling. There are four theorems to be discussed. The first theorem proves that path is super vertex magic if and only if is odd and . The second theorem proves that cyclic is super vertex magic if and only if is odd. The third theorem proves that bijection function from an edge set onto of graph can be extended to a super vertex magic labeling if and only if the set amount of edge label that incidents with a vertex in the graph, consists of sequential integers as many as vertices in the graph. The fourth theorem proves that disjoint union of the cyclics consists of cyclics with each cyclic has vertices is super vertex magic if and only if and are odd.
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