Perbedaan Gangguan Pendengaran Akibat Bising antara Operator Ccr Pltu dengan Pltgudi PT Pjb Up Gresik

The role of central control room (CCR) operator in Steam Power Plant (PLTU) or Gas and Steam Power Plant (PLTGU) of a work environment has high noise intensity with range (62.2– 99.8 dBA). Noise resulting from the process of production of electrical energy by machinery such as power generation unit boiler/HRSG, turbine, generator, condenser and other supporting equipment can cause Noise Induced Hearing Loss (NIHL). Study with cross-sectional design aims to analyze the difference in Noise Induced Hearing Loss between shift operator CCR PLTU and PLTGU PT PJB UP Gresik. Research on samples taken with the technique of simple random sampling with the majority of respondents were ≥ 40 years old, have a working periode ≥ 4 years, have a work area with a level of intensity noise > 85 dBA, long exposure noise ≤ 1 hour and good level of compliance of the use of ear protection in both of units. There was a difference of NIHL shift operator CCR PLTU and PLTGU. The number ofoperator who have experienced hearing loss due to noise on the shift operator CCR PLTU greater than PLTGU. Shift operator CCR PLTU and PLTGU are advised to obey and comply with safe working hours in areas with particular noise intensity has been set and the use of ear protection with right, also have to perform regular an audiometry exam tests so that the function of hearing of shift operator CCR could in monitor continuously

Who uses foodbanks and why? Exploring the impact of financial strain and adverse life events on food insecurity

Background Rising use of foodbanks highlights food insecurity in the UK. Adverse life events (e.g. unemployment, benefit delays or sanctions) and financial strains are thought to be the drivers of foodbank use. This research aimed to explore who uses foodbanks, and factors associated with increased food insecurity. Methods We surveyed those seeking help from front line crisis providers from foodbanks (N = 270) and a comparison group from Advice Centres (ACs) (N = 245) in relation to demographics, adverse life events, financial strain and household food security. Results About 55.9% of foodbank users were women and the majority were in receipt of benefits (64.8%). Benefit delays (31.9%), changes (11.1%) and low income (19.6%) were the most common reasons given for referral. Compared to AC users, there were more foodbank users who were single men without children, unemployed, currently homeless, experiencing more financial strain and adverse life events (P = 0.001). Food insecurity was high in both populations, and more severe if they also reported financial strain and adverse life events. Conclusions Benefit-related problems appear to be a key reason for foodbank referral. By comparison with other disadvantaged groups, foodbank users experienced more financial strain, adverse life events, both increased the severity of food insecurity

Improvement of salt raw material procurement and inventory planning at Bitung

The aim of this study is to integrate demand forecast, determine the quantity of raw material requirements, and select the best supplier for the salt production process accurately. The steps start from demand forecasting, continue with supplier selection based on some criteria, and comparison between percentage of inventory costs and percentage of total costs in existing and proposed methods. After changing the period, the smallest error was achieved from moving average with 5 periods. The forecasting result was converted to raw materials in one period. Using Analytical Hierarchy Process, some supplier criteria like price, quality, service and delivery will give the total priority value of supplier A 0,356, supplier B 0,170, supplier C 0,249, supplier D 0,133, and supplier E 0,092. Supplier A became a selected supplier. The proposed method could decrease the percentage of stock out costs from 79,49% to 30,95%, but the percentage of saving cost increase from 20,35% to 68,62%. In total, the proposed method will save Rp2.587.609 or 28,61% from the existing method for six months

APLIKASI KONTROL OPTIMAL LQG UNTUK PENGENDALIAN WATER LEVEL STEAM DRUM BOILER DI PG. KEBON AGUNG MALANG JAWA TIMUR

Steam drum adalah bagian penting dari boiler, di dalamnya terjadi proses perubahan dari air menjadi uap (steam) berlangsung secara kontinyu. Level air pada steam drum boiler harus dijaga pada NWL (Normally Water Level), level tidak boleh terlalu rendah atau tinggi dari NWL. Level drum yang terlalu rendah bisa menyebabkan terjadinya panas berlebih (overheated) pada boiler tubes sehingga tubes bisa menjadi rusak. Sebaliknya level drum yang terlalu tinggi akan menyebabkan kualitas steam yang dihasilkan kurang bagus (banyak mengandung air/basah), hal ini dapat menyebabkan korosi pada peralatan yang menggunakan steam sebagai penggeraknya. Perubahan water level pada steam drum bisa terjadi akibat, perubahan kebutuhan steam yang digunakan pada proses produksi. Sistem pengendalian water level pada steam drum, mempunyai gangguan berupa perubahan kebutuhan steam ataupun noise dari pembacaan sensor ketinggian. Salah satu metode sistem kontrol optimal yang dapat mengkompensasi kedua masalah tersebut, adalah kontrol optimal dengan metode LQG (Linier Quadratic Gaussian). Digunakannya metode kontrol optimal LQG, bertujuan untuk mengoptimalkan kemampuan yang dimiliki oleh valve agar dapat mengatasi gangguan yang diberikan oleh perubahan laju steam dan pengukuran yang dikotori noise. Sehingga level dari steam drum bisa dipertahankan di dalam range yang diperbolehkan. Dari hasil percobaan, respon water level memiliki Ts=1100 s dan Ess=0.067% saat mode pertama. Ketika mode kedua Ess=0.13%.Kata Kunci :NWL, disturbance, LQG

A Dietary Microcapsule Based on Single Cell Protein (Spirulina Platensis) for Milk Fish, Chanos-chanos, Larvae

The purpose of this study was to evaluate differences between spirulina-based microcapsules and commercial diets on absolute, daily and specific growth and survival rates of milkfish larvae. Spirulina platensis was as a core diet in microcapsules with different matrix (walls). The first capsule wall was gelatin and fish oil, while the second capsule wall was gelatin, fish oil and whole egg. The control group was commercial diet. A total of 1200 larvae were used in this experiments using recirculation systems. Larvae are fed three times a day and increased regularly when the size of the larvae increases. The results showed that the effect of both sprirulina-based microcapsule diets on the absolute growth rate (AG), specific growth rate (SGR) and average daily growth rate (ADGR) of Chanos-chanos larvae fed spirulina-based microcapsule same as them which to be fed using commercial diet. The survival rate was as 80.6±11,171%; 84.6±8.443%; 83.8±16.496%, respectively. This study showed that Spirulina-based microcapsules had the same effect as commercial feed on the growth of milkfish larvae which means that this diet could replace commercial diet