Judul: Penjadwalan Kamar Operasi Menggunakan Pemrograman Linear Bilangan Bulat
Abstrak: Operating room scheduling in hospitals is undertaken based on a master surgery schedule, which can be formulated manually or by using mathematical programming. Some hospitals, such as state owned hospitals, receive budget or subsidy from the government to carry out its daily management, including surgery services. But for some reason, government may reduce the budget. The impact of budget cuts to hospitals is immediate. They must adjust the operating time and the number of operating rooms in services. In this work, operating room scheduling problem is modeled in the form of an integer linear programming. The objective function is formulated to maintain as much as possible the proportion of service time in each surgical division, although work hours and the number of operation rooms are reduced. As a case study, we consider a scheduling problem in a hospital with 6 surgical divisions and 4 types of operating rooms, which gives a total of 14 rooms. We discuss three schedulling adjustments, namely (i) model 1: total operating time is obtained by reducing the number of operating rooms, (ii) model 2: total operating time is obtained by reducing the number of operating rooms more than that of model 1, (iii) model 3: total operating time is obtained by reducing the total of work hours, while the number of operating rooms is as model 1. The results obtained are in the form of schedules that minimize the differences of time allocation between master surgery schedule and the new schedule.
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Judul: Penjadwalan Perawat Rumah Sakit Menggunakan Integer Linear Programming
Abstrak: Dampak dari Pembatasan Sosial Berskala Besar diperlukannya penjadwalan ulang staf/personel dari jadwal yang sudah ada. Penjadwalan perawat merupakan masalah penting bagi rumah sakit, sehingga diperlukan pengelolaan penjadwalan yang tepat. Penjadwalan secara otomatis dapat dilakukan dengan bantuan software seperti LINGO. Dalam karya ilmiah ini, permasalahan penjadwalan dapat dimodelkan sebagai masalah integer linear programming lalu akan dibuat ke dalam 5 skenario berbeda. Fungsi objektifnya adalah meminimumkan biaya keseluruhan yang harus dikeluarkan Rumah Sakit sesuai dengan peraturan atau kendala yang ada di rumah sakit. Penjadwalan dengan lima skenario akan dimasukkan ke dalam proses komputasi dan diselesaikan dengan bantuan software LINGO 18.0, The impact of large-scale social restrictions necessitates rescheduling of staff or personnel from the existing schedule. Nurse scheduling is an important issue for hospitals, so proper scheduling management is needed. Automatic scheduling can be done by software such as LINGO. In this scientific paper, scheduling problems can be modeled as integer linear programming problems and then divided into 5 different scenarios. Its objective function is to reduce the overall costs must be incurred by the hospital with the hospital's regulations or constraints. Scheduling with five scenarios will be included in the computation process and solved with software LINGO 18.0.
Keyword: Hospital, Integer Linear Programming, Nurse Scheduling

Judul: Durability of Specific Immunoglobulin (Ig) Y Againts Influenza and Covid-19 in Sunscreen
Abstrak: The benefit of specific immunoglobulin Y (Ig Y) as an active ingredient in personal care products such as sunscreen has not been properly studied. Our study aims to evaluate the reliability of specific IgY against influenza and the COVID-19 virus in a sample sunscreen product. Specific IgY influenza and COVID-19 viruses were inserted in the sample sunscreen at two concentrations of 0.1% and 0.25%. Three treatments were observed: control (C) sunscreen without IgY, treatment 1 (T1) sunscreen with 0.1% IgY, and treatment 2 (T2) sunscreen with 0.25% IgY. Organoleptic observations were carried out to monitor changes in aroma, color, and texture, and sunscreen sampling was done every week for 6 weeks. The durability of IgY was evaluated using an enzyme-linked immunosorbent assay (ELISA) and a neutralization assay. Organoleptic observation from weeks 1 to 6 showed consistency in its aroma, color, and texture. Enzyme-linked immunosorbent assay and neutralization assay (NA) results of the T1 and T2 groups showed negative results except for sample T1 at week 5, which showed a positive result in the Influenza A ELISA. Based on the results, it seems that IgY concentrations of 0.1% or 0.25% were not optimal. However, this negative result might be due to low concentration of the IgY and the presence of beeswax, which inhibits IgY and causes it to dissolve in distilled water, thus preventing it from being detected in the assay.
Keyword: Immunoglobulin Y, Sunscreen, Influenza, COVID-19, Biological Activity