Comparative Analysis of Time Series Methods LSTM and ARIMA for Predicting Inventory Availability (Case Study: PT XYZ)

Product availability plays a crucial role in supply chain management, directly impacting all aspects of business operations, from production to distribution. This study analyzes the optimization of product availability at PT. XYZ, a frozen and chilled food trading company in Indonesia, focusing on four main commodities: beef, buffalo meat, chicken, and potatoes. Utilizing historical transaction data from 2020 to July 27, 2024, this research compares the performance of two forecasting models: ARIMA (AutoRegressive Integrated Moving Average) and Long Short-Term Memory (LSTM), in predicting product availability The traditional ARIMA model has proven effective in time series data analysis but has limitations in capturing complex patterns and non-linear fluctuations. LSTM, as a machine learning technique, demonstrates superiority in capturing long-term temporal relationships. This study finds that the LSTM model consistently outperforms ARIMA for beef, buffalo meat, and chicken categories, although there is a slight increase in error for the potatoes category. Model performance evaluation is conducted using metrics such as Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), and Root Mean Squared Error (RMSE). The results indicate that the LSTM model exhibits lower errors compared to ARIMA, proving its effectiveness in predicting dynamic demand patterns. With a better understanding of product availability, the company is expected to reduce operational costs, avoid losses, and enhance customer satisfaction through more efficient supply chain management. This research provides significant insights for PT. XYZ and similar industries in implementing more accurate forecasting methodologie

Nanocrystalline Zeolite Y: Synthesis and Heavy Metal Removal

Lead (Pb) and chromium (Cr) are common groundwater contaminants at industrial installation. Zeolites are widely use as an adsorbent in heavy metal removal. Nanocrystalline zeolite Y has been synthesised from a clear solution at 1500C by using aluminum isopropoxide (Al(OiPr)3 and Ludox LS as alumina and silica source, tetramethylammonium hydroxide (TMAOH) and tetramethyl ammonium bromide (TMABr) as first and second organic template, respectively. The products were characterised by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) to identify the structure and particle sizes. After 48 hours synthesis time, nanocrystalline zeolite Y samples were obtained with approximately average particle sizes of 268 and 119 nm for one and two organic templates, respectively. The synthesized nanocrystalline zeolite Y was applied for some metal adsorption including Pb(II) and Cr(III) and the results show that the nano crystal samples have good performance. The removal efficiency for Pb and Cr could be up to 88.97% depending on the initial concentration and temperature. The adsorption isotherms of Cr and Pb were determined from the Langmuir and Freundlich equations. The equilibrium sorption capacities (Qe) from the Langmuir equation were 270.27 mg/g and 204.08 mg/g at 300C for Pb and Cr, respectively. Kinetic adsorption analysis of nanozeolite Y shows that the pseudo second order kinetics would be better for fitting the dynamic adsorption of both Cr and Pb cations.Key words: adsorption isotherms, kinetic adsorption analysis, nanocrystalline zeolite

MOBILITAS UNSUR LOGAM PADA HABITAT MANGROVE DAN KORELASINYA DENGAN LIMBAH INDUSTRI DAN KUALITAS TAMBAK

Changing Mangrove shore land into farms and settlements, resulting in further degradation of coastal environments. Some cases which arise due to the high metal pollution can not be reduced by mangroves. Changes in mangrove environmental improvements will decrease the accumulation of metals, because it has obtained data that mangroves are able mengabsorb fires resulting in lower metal solubility in water. The study aimed to assess the metal content in some mangrove and pond habitats, studying the feasibility or the quality of maintenance of sediment ponds for milkfish, and determine the relationship between the quality of sediment by the end of biomass production (PROD), dense stocking density (STD) and survival rate (SR) as well as changes quality of water

ANALISA BIAYA PEMBUATAN MOLD PRINTER DENGAN METODE QUALITY FUNCTION DEPLOYMENT DI PT. INDONESIA EPSON INDUSTRY

Pertumbuhan pesat pada penggunaan produk plastik terutama hasil dari injection molding di industri manufaktur sangat berguna dan memiliki nilai ekonomis yang tinggi. Injection molding banyak dipilih karena memiliki beberapa keuntungan diantaranya, kapasitas produksi yang tinggi, sisa penggunaan material (useless material) sedikit dan kebutuhan tenaga tergolong minimal. Metode perancangan yang dipilih adalah quality function deployment yang bertujuan menganalisa biaya pembuatan mold printer baru tahun 2014 di PT. Indonesia Epson industry. Produk plastik pada model printer Deniro mencapai 47% dari keseluruhan komponen atau part di dalam 1 model printer, sedangkan untuk komponen yang lain yaitu, press parts 18%, shaft 11%, rubber, spring dan others parts mencapai 20%. Dari spesifikasi tersebut didapatkan kesimpulan bahawa komponen part plastik merupakan peluang yang besar untuk aktifitas efisiensi, karena semakin banyak mold maka semakin banyak investasi yang harus dikeluarkan, oleh karena itu perlu dilakukan perancangan konsep untuk efisiensi. Perancangan yang diajukan adalah perubahan dari standard mold menjadi family mold, konsep rangcangan part dan mold dibahas pada saat proses part design review dan mold design review. Kata kunci: injection molding, rancangan, efisiensi

Studi Eksperimental Kekuatan Struktur Atap Berongga Berbahan Komposit Serat Alam

Komposit adalah suatu bahan yang terbentuk dari gabungan dua bahan atau lebih sehingga bahan komposit yang dihasilkan memiliki sifat dan karakteristik mekanik yang berbeda dengan bahan penyusunnya, serat yang digunakan dalam komposit matrik dibedakan menjadi dua yaitu serat alam dan serat sintetik. Sedangkan padi dan nanas merupakan tumbuhan yang banyak dijumpai di seluruh nusantara khususnya indonesia, sehingga hasil alam seperti beras dan nanas di indonesia sangat melimpah. Sekam padi merupakan bahan alternatif yang dapat digunakan dalam pembuatan material komposit, demikian pula serat daun nanas yang akan digunakan sebagai bahan atap merupakan cara yang baik untuk mengurangi evolusi limbah alam seperti sekam padi dan serat daun nanas. . Pada penelitian ini, penulis akan melakukan percobaan kekuatan mesin berbasis komposit menggunakan sekam padi dan serat daun nanas khususnya pada pembuatan atap hollow. Dari uji tarik yang telah dilakukan pada komposit serat sekam padi dan serat daun nanas dengan perbandingan komposisi resin 70% : 30% sekam padi dan daun nanas, 80% : 20% dan 90% : 10%. Terlihat komposisi bahan 90% : 10% mendapatkan nilai lebih tinggi yaitu 101,4 kgf/mm2, sedangkan untuk uji perbandingan perbandingan komposisi resin adalah 70% : 30% sekam padi dan serat daun nanas 80% : 20% dan 90% : 10%. Terlihat bahwa komposisi material 90% : 10% mendapatkan nilai yang lebih tinggi yaitu 1246,26 kgf/mm2

Adsorption of Cu (II) Heavy Metal From Acid Mine Drainage Using Modified Bentonite With Risk Husk Activated Carbon

Abstract: Acid mine drainage is a waste product of the mining process that contains several heavy metals, including copper. The purpose of this study was to develop bentonite adsorbent-modified activated carbon from rice husks that will be used to adsorb Cu metal from acid mine drainage. Bentonite was chemically activated with HCl, whereas rice husk was physically and chemically activated in a furnace at 500°C for 2 hours and soaked in HCl. The modification was accomplished by combining activated bentonite and rice husk activated carbon in variations of ratio, which are 1:1, 1:2, 1;3, 1:4, and 1:5. Morphological analysis revealed a surface structure similar to that of coral (sponge). The functional groups identified include the OH, OH2, Al, SiO, SiOAl, and SiOSi functions. The XRD analysis showed a diffractogram at 2θ = 19000o and 20000o that indicates the presence of montmorillonite minerals. The Cu metal adsorption capacity of rice husk-modified bentonite was 3.153 mg/g. The adsorption isotherm obtained in this study is the Freundlich isotherm, with an R2 value of 0.9541. These findings indicate the potential usefulness of the modified adsorbent in mitigating the environmental impact of the industry dealing with acid mine drainage.Abstrak: Air asam tambang merupakan limbah hasil proses penambangan yang mengandung beberapa logam berat, diantaranya tembaga. Tujuan penelitian ini adalah mengembangkan karbon aktif termodifikasi adsorben bentonit dari sekam padi yang akan digunakan untuk mengadsorpsi logam Cu dari air asam tambang. Bentonit diaktivasi secara kimia dengan HCl, sedangkan sekam padi diaktivasi secara fisik dan kimia dengan tanur pada suhu 500°C selama 2 jam dan direndam dalam HCl. Modifikasi dilakukan dengan menggabungkan bentonit aktif dan karbon aktif sekam padi dengan variasi perbandingan 1:1, 1:2, 1;3, 1:4, dan 1:5. Analisis morfologi mengungkapkan struktur permukaan yang mirip dengan karang (spons). Gugus fungsi yang teridentifikasi meliputi fungsi OH, OH2, Al, SiO, SiOAl, dan SiOSi. Analisis XRD menunjukkan difraktogram pada 2θ = 19000o dan 20000o yang menunjukkan adanya mineral montmorillonit. Kapasitas adsorpsi logam Cu pada bentonit termodifikasi sekam padi adalah 3,153 mg/g. Isoterm adsorpsi yang diperoleh pada penelitian ini adalah isoterm Freundlich, dengan nilai R2 sebesar 0,9541. Temuan-temuan ini menunjukkan potensi kegunaan adsorben yang dimodifikasi dalam mengurangi dampak lingkungan bagi industri yang berurusan dengan limbah air tambang asam

Recovery Process of Condensate the Ammonia Wastewater Plant of PT.PIM with A Combination of Technology Air Stripping Jet Bubble Colum, Advance Oxidation process and Ion Exchange Resin

Abstract   Study of reducing the content of ammonia, carbon dioxide and organic contaminants in wastewater process condensate using a combination of technologies of water Jet Stripping Bubble Colum, Advance Oxidation Process and Ion Exchange Resin have been done. The aims of this research is to look the effect of hydraulic resident time in Jet Stripping Bubble Colum and the amount of the addition of Ozon/H2O2 to reduction the content of carbon dioxide and organic contaminants as well as ammonia removal with ion exchange resin on the process condensate so that can be reuse as boiler feed water in ammonia plant of PT. PIM. This research was conducted using a combination Air Stripping Jet Bubble Colum, Advance Oxidation Process and Ion Exchange Resin which equipped with water and air flows adjustment. The water flow enter the column, pressure of the Colum and diameter of nozzle was maintained constantnts during experiment, while the air flow rate enter to the column, H2O2/O3 concentrations and the hydraulic retention time was vary  respectively. The results showed that the water Jet Stripping Bubble Colum at 50 Psi air pressure capable of achieving CO2 lowers 87.60% and ammonia to 65.31%. AOP technology capable of lowering the content of organic contaminant to 80.71% with the addition of hydrogen peroxide 8,000 ppm with a residence time 180 minutes. While the ammonia remaining in the water the process of condensate action exchange resin using eliminated with a reduction of ammonia reached 98.57%, so that the recovery process of water condensate technology uses a combination of Air Stripping Jet Bubble Colum, Advance Hydrocarbon processes (AOP) and Ion Exchange Resins already meets the requirements of viable reuses boiler feed water. The ammonia reduction was determined by using ASTM-D 1426 method, the carbon dioxide by using ASTM-512 method, and the organic contaminants by using titrimetric method (SII-0071).   Keyword   :  Air Stripping Jet Bubble Colum, Advance Oxidation Process (AOP), Ammonia Removal, Carbon Dioxide Removal

Response Surface Methodology Approach to the Optimization of Cyclone Separator Geometry for Maximum Collection Efficiency

A Response surface methodology coupled with a Box-Behnken design experiment has been utilized to optimize geometry parameters of a cyclone as a gas-solid separator in an effort to obtain a maximum particle collection efficiency. Independent variables being optimized include seven geometry parameters of inlet height (a/D), inlet width (b/D), vortex finder height (S/D), vortex finder diameter (De/D), total cyclone height (Ht/D), cylinder height (h/D), and cone tip diameter (Bc/D). A number of 62 treatments were performed following Box-Behnken experimental design of seven factors and three levels (-1, 0 and +1). The response variable, the cyclone collection efficiency, was calculated in accordance with the Muschelknautz model using a spreadsheet software. The relationship between the response variable and independent variables was mathematically expressed according to a quadratic polynomial equation calculated with the aid of Design Expert software.  The results of the research showed that among seven variables being investigated, there are only five cyclone geometry parameters which significantly affected the cyclone collection efficiency, including inlet height (a/D), inlet width (b/D), vortex finder height (S/D), vortex finder diameter (De/D) and total cyclone height (Ht/D).  The optimization was then conducted to include these five variables that significantly affected the collection efficiency and neglected the remaining other two variables.  The optimization computation was run in the Design Expert statistical software by setting a maximum possible value for the collection efficiency. The maximum collection efficiency of 91.244% was obtained when the independent variables of inlet height a/D=0.8, inlet width b/D=0.38, vortex finder height S/D=0.69, vortex finder diameter De/D=0.575 and total cyclone height Ht/D=3.12.  Validation of this statistical finding was tested again and compared with the result of Muschelknautz model calculation to give a significantly small error of 0.82%

Analysis of the potential of landfill gas as an alternative for electrical energy source

Municipal solid waste (MSW) is generated from human activities, where most of them end up at the landfill. The landfill gas produced from the degradation of organic matter in the MSW landfill contains methane can be used as the energy source. Therefore, the objective of this research is to analyze the potential of landfill gas as an alternative for energy source. Two Landfill Simulator Reactor (LSRs) made of high density polyethylene (HDPE) pipe has 50 cm outside diameter and 150 cm of height were operated under natural condition. The first LSR was operated without leachate recirculation (A), while the other one was operated with leachate recirculation (B). Results of this research found the highest methane concentration from LSR A was about 53% and 41.8% from LSR B. This finding was applied to estimate the landfill gas production for electricity generation in Cot Padang Nila landfill. The potential electrical energy that could be produced from Cot Padang Nila landfill is 203 MWh/year if it is operated using LSR A mode, and 161 MWh/year when operated in accordance to LSR B mode. This amounts of energy is suitable to provide electricity for 53-67 households in the vicinity of the landfill

Comparative analysis of HHV and LHV values of biocoke fuel from palm oil mill solid waste

This research aims to investigate and compare the energy value of different biocoke and raw palm oil-biomass. Applying pressure and heating simultaneously during biocoke production is a direct method used in this research. The results of the proximate analysis showed that the water content in each sample tested was below 10%. The water content can be reduced to 5% for all samples except oil palm-midrib. The highest raw biomass heating value was recorded from palm-kernel-shell at 16.83 MJ/kg; the lowest oil palm-midrib was 14.60%. Meanwhile, the highest lower heating value was recorded from biocoke at 19.08 MJ/kg, and the weakest empty-fruit-bunches 17.01 MJ/kg