scholarly journals Optimalisasi Sistem Persediaan Bahan Baku Karet Mentah (Lateks) dengan Metode Lot Sizing (Studi Kasus: PT Abaisiat Raya)

2016 ◽  
Vol 12 (1) ◽  
pp. 317 ◽  
Author(s):  
Dina Rahmayanti ◽  
Ahmad Fauzan
Keyword(s):  
Inventory Management ◽  
Lot Sizing ◽  
Demand Forecasting ◽  
Crumb Rubber ◽  
Optimal Size ◽  
Lot Size ◽  
Planning Period ◽  
Safety Stock ◽  
Reorder Point

PT Abaisiat Raya is one of the manufacturers of rubber crumb (crumb rubber) in the city of Padang. Latex inventory management system at PT Abaisiat Kingdom basically signinfikan still need improvement. It is based on the planning activities in the warehouse inventory of raw materials firms irregular, thus causing excess stock (over stock) at a time and shortage of stock (stock out) at other times. Process optimization is done with latex inventory system involving factors such as demand forecasting production planning or latex needs during the period of next 12 (in 2012), the costs involved, the waiting time (lead time), the implementation of forecasting methods, determination of size lots (lot sizing), the determination of safety stock (safety stock), and re-ordering time (reorder point), so the output will get a number of requests are for 12 periods ahead, the size of each reservation period, the total cost is required, when re-ordering will be done , as well as how much inventory to latex in the warehouse. Based on these results, it was found that the optimal size of the book is the same as the demand for each period (reservation is made each period) due to a cyclical pattern of demand and decreases throughout the planning period. Value of the stock or safety stock is located in Kg 114,282.20, and re-ordering time (reorder point) to cope with fluctuations do when the stock has reached a level of 333,130.95 kg.Keywords: Forecasting, Time Wait, Lot Size, Safety Supplies, Reorder

scholarly journals Implementation of inventory management in footwear industry

2021 ◽  
Vol 14 (2) ◽  
pp. 360
Author(s):  
Jeferson Conceição ◽  
José De Souza ◽  
Elton Gimenez Rossini ◽  
Alfonso Risso ◽  
Alexandre Beluco
Keyword(s):  
Inventory Management ◽  
Demand Forecasting ◽  
Economic Order Quantity ◽  
Economic Order ◽  
Order Quantity ◽  
Lot Size ◽  
Safety Stock ◽  
Forecasting Method ◽  
Abc Analysis ◽  
The Moment

Purpose: The objective of this research was to implement new inventory management in a footwear company through the analysis of indicators obtained from inventory data collection.Design/methodology/approach: The methods of ABC analysis, demand forecasting, safety stock, reorder point and economic order quantity were applied. The items in inventory were classified by order of financial importance through ABC analysis, and the proposed indicators were analyzed to determine the moment the inventory replenishment should be carried out as well as the purchase lot size for each item. The research also analyzed the behavior of the demand and pointed out the demand forecasting method that came closest to reality.Findings: The study presents a method of implementing inventory management based on indicators derived from the application of ABC curve methods, demand forecasting, safety stock, re-fulfillment point, and economic purchased lot. It also indicates how the ABC classification of stocks can be used to check the most representative materials in stock. The study also highlights that the rejection of modifications can be surpassed by obtaining favorable results.Research limitations/implications: The inventory management applied in this work is based on indicators that resulted in two main data which were able to define the size of the purchase lot to be ordered and the amount of material needed.Practical implications: The methods of ABC analysis, demand forecasting, safety stock, reorder point and economic order quantity were applied. The items in inventory were classified by order of financial importance through ABC analysis, and the proposed indicators were analyzed to determine the moment the inventory replenishment should be carried out as well as the purchase lot size for each item. The research also analyzed the behavior of the demand and pointed out the demand forecasting method that came closest to reality.Originality/value: In this study, a method applied is presented, highlighting the importance of the methodological application for the implementation of inventory management. The study contributes to the encouragement and adoption of methodologies to improve analysis and inventory management in companies.

scholarly journals ANALISIS PERENCANAAN PERSEDIAAN BAHAN BAKU PAKAN TERNAK DENGAN MENGGUNAKAN METODE LOT SIZING (Studi Kasus Pada PT. Japfa Comfeed Indonesia Tbk, Unit Makassar)

ARIKA ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 29-36
Author(s):  
A. Besse Riyani Indah ◽  
Sapta Asmal ◽  
Khalifah Amalia ◽  
Dian Pratiwi Sahar ◽  
Gerard Antonini Duma
Keyword(s):  
Wheat Bran ◽  
Lot Sizing ◽  
Moving Average ◽  
Exponential Smoothing ◽  
Lot Size ◽  
Safety Stock ◽  
Reorder Point ◽  
Fixed Period ◽  
Single Exponential ◽  
Weighted Moving Average

Permasalahan yang dihadapi perusahaan adalah tingginya total biaya persediaan pada bahan baku pakan ternak kategori mayor dalam penelitian ini bahan baku tersebut diantaranya Jagung Lokal, Wheat Bran Pellet, Biji Batu dan Katul. Oleh karena itu, penelitian ini bertujuan untuk mengoptimalkan kuantitas pemesanan (lot size) agar diperoleh total biaya yang minimum. Pada penelitian ini dilakukan perencanaan persediaan menggunakan Fixed Period Requirement (FPR) dan Algoritma Wagner-Whitin (AWW) dengan mempertimbangkan kuantitas pemesanan. Langkah awal yang dilakukan ialah peramalan permintaan menggunakan Weighted Moving Average dan Single Exponential Smoothing, kemudian dilakukan perbaikan terhadap manajemen persediaan bahan baku pakan ternak kategori mayor, dengan menentukan safety stock dan reorder point, kuantitas pemesanan optimal, dan total biaya persediaan. Hasil dari penelitian yang dilakukan ialah diperoleh safety stock dan reorder point setiap jenis material untuk mengantisipasi apabila terjadi stock out, serta lot size yang optimal agar tidak terjadi overstock. Hasil yang didapatkan setelah melakukan perhitungan menggunakan  FPR adalah sebesar Rp. 68.836.795.791 dan AWW menunjukkan hasil sebesar Rp 3.216.795.791 Berdasarkan hasil tersebut maka metode yang menghasilkan total biaya minimum adalah  AWW.

scholarly journals MATERIAL REQUIREMENT PLANNING UNTUK MEMENUHI PRODUKSI PADA CV. BANGUN CIPTA ARTHA DI BADUNG

2020 ◽  
Vol 9 (2) ◽  
pp. 426
Author(s):  
I Made Sugita Yasa ◽  
Kastawan Mandala
Keyword(s):  
Inventory Management ◽  
Lot Sizing ◽  
Raw Materials ◽  
Raw Material ◽  
Exact Order ◽  
Lot Size ◽  
Inventory Costs ◽  
Material Requirement Planning ◽  
Material Requirement ◽  
Total Inventory

Inventory management without Material Requirement systems in CV. Bangun Cipta Artha resulted in the lot size for each order of raw materials not optimal. One concept that can be used to plan and control raw materials is the Material Requirement Planning. This study is to determine the number of sizes of raw material orders, the exact order time, the method that produces the lowest cost for each raw material, and the effect of using MRP on inventory costs. This research conducted on 160x200cm spring bed products. Data was analyzed by making production master schedules, determining net requirements, determining lot size, and making MRP tables. Based on the results, the determination the best lot sizing is the order quantiy period which results in a total inventory cost of Rp. 26,475,220 where the total cost is lower, compared to lot for lot method which Rp. 43,464,000. part period balancing Rp. 33,106,576, and conventional method Rp.49,472,912. Keywords: Material Requirement Planning (MRP), Sizing Lot, Lot For Lot, Balancing Part Period, Period Order Quantiy

scholarly journals Optimal pricing and lot-sizing decisions under Weibull distribution deterioration and trade credit policy

2008 ◽  
Vol 18 (2) ◽  
pp. 221-234
Author(s):  
S.K. Manna ◽  
K.S. Chaudhuri ◽  
C. Chiang
Keyword(s):  
Weibull Distribution ◽  
Trade Credit ◽  
Lot Sizing ◽  
Retail Price ◽  
Lot Size ◽  
Credit Period ◽  
Two Parameter ◽  
Weibull Distribution Deterioration ◽  
Dependent Demand

In this paper, we consider the problem of simultaneous determination of retail price and lot-size (RPLS) under the assumption that the supplier offers a fixed credit period to the retailer. It is assumed that the item in stock deteriorates over time at a rate that follows a two-parameter Weibull distribution and that the price-dependent demand is represented by a constant-price-elasticity function of retail price. The RPLS decision model is developed and solved analytically. Results are illustrated with the help of a base example. Computational results show that the supplier earns more profits when the credit period is greater than the replenishment cycle length. Sensitivity analysis of the solution to changes in the value of input parameters of the base example is also discussed.

scholarly journals Decreasing Total Inventory Cost by Controlling Inventory in Motorcycle Dealer

2020 ◽  
Vol 22 (2) ◽  
pp. 41-49
Author(s):  
David ◽  
Engmir ◽  
Irwan Budiman ◽  
Jusra Tampubolon
Keyword(s):  
Inventory Management ◽  
Demand Forecasting ◽  
Spare Parts ◽  
Order Quantity ◽  
Inventory Cost ◽  
Safety Stock ◽  
Safety Stocks ◽  
Forecasting Method ◽  
Total Inventory ◽  
Abc Analysis

This research was conducted at one of the motorcycle dealers in Indonesia. Besides selling motorcycles, this dealer also provides services to repair motorcycles and sells genuine motorcycle parts. Inventory management which the company carried out is still not good enough because there are still demand for spare parts from consumers that cannot be fulfilled by the company. The purpose of this study is to draw up a plan to control spare parts by paying attention to the spare parts that need to be considered, estimating the exact number of spare parts demand, knowing the smallest total inventory cost, knowing the amount of safety stock needed, and knowing when to reorder. In preparing the spare parts control, the methods used are ABC analysis, demand forecasting method, and EOQ method. The results of this study are plans to control the inventory of Tire, Rr. such as the forecasting sales of Tire, Rr. as many as 17338, economic order quantity of Tire Rr are 2158 units, the number of safety stocks of Tire, Rr. needed in 2020 are 1738 units, and the reorder point in 2020 is 8 times with the total inventory cost for Tire, Rr. in 2020 is Rp. 30,009,005.

scholarly journals Joint determination of preventive maintenance and buffer stock for a production unit under lease

2018 ◽  
Vol 11 (3) ◽  
pp. 497 ◽  
Author(s):  
Thanawath Niyamosoth ◽  
Supachai Pathumnakul
Keyword(s):  
Mathematical Model ◽  
Preventive Maintenance ◽  
Buffer Stock ◽  
Production Unit ◽  
Maintenance Cost ◽  
Optimal Size ◽  
Safety Stock ◽  
Joint Determination ◽  
Optimal Period

Purpose: The purpose of this work is to develop a mathematical model for simultaneously determining the optimal period of preventive maintenance actions and the optimal size of buffer stock for a production unit that is owned by a lessor and leased to a lessee under a lease contract.Design/methodology/approach: A mathematical model is formulated and a numerical procedure is developed for finding the optimal period of preventive maintenance actions and the optimal size of buffer stock to minimize the total expected costs considering both a lessor and a lessee over a lease period.Findings: The proposed model gives better solutions than those where the maintenance cost to the lessor and the production inventory cost to the lessee are minimized separately.Originality/value: The joint determination of preventive maintenance and safety stock is a topic that has been extensively studied for decades. The majority of the models reported in the literature implicitly assume that the firm owns the production unit and maintenance actions are done in-house. However, equipment acquisition through leasing is a common practice nowadays. Normally, under a lease contract, the lessor who owns the equipment is responsible for maintenance services. This may lead to a conflict between the lessor and the lessee concerning the optimal choice of maintenance actions. To solve this conflict, we propose a joint determination of preventive maintenance and safety stock model for a production unit under a lease. The objective of our model is to simultaneously determine the optimal period of preventive maintenance actions that the lessor needs to perform and the optimal size of buffer stock the lessee needs to produce so that the total combined expected costs to both parties over the lease period are minimized.

scholarly journals Analisis Pengendalian Persediaan Sistem Manajemen Persediaan Bahan Baku Kemasan

2018 ◽  
Vol 4 (2) ◽  
pp. 65
Author(s):  
Suryani Suryani ◽  
Dedi Can
Keyword(s):  
Data Processing ◽  
Inventory Management ◽  
Raw Materials ◽  
Demand Analysis ◽  
Safety Stock ◽  
Class A ◽  
Reorder Point ◽  
Spss Software

Inventory is one of the things that must be considered by the company. One way is to manage inventory management. The problem that occurs in the research location is the lack and excess stock for packaging raw materials. This lack of capital is due to the absence of calculations for the number of safety stock and reorder points, the cause of excess inventory is the excess in the absence of groupings of packaging raw materials to find out which products are more critical according to demand. Analysis of system improvements focuses on packaging raw materials. Based on the results of data processing obtained from 304 existing packaging raw materials, there are 15 packaging raw materials in class A. Processing is focused on class A only. Forecast calculations using SPSS software. And processing is continued by using the size-reorder point systems lot method with quantity results, reorder margin and safety stock that varies 15 raw materials according to the calculations performed.

scholarly journals Evaluating The Performance of Inventory Management The Production Division of PT. Tiga Serangkai Surakarta as a Case Study

2016 ◽  
Vol 1 (1) ◽  
pp. 93
Author(s):  
Sri Maryati
Keyword(s):  
Inventory Management ◽  
System Performance ◽  
Service Level ◽  
Inventory System ◽  
Order Quantity ◽  
Safety Stock ◽  
Production Employee ◽  
The Cost

This research aims to understand the process of production and to analyze the performance of inventory system on production division of PT. Tiga Serangkai. The data has been gathered from direct observation of the process production and warehouse and the interview with the production employee, the employee of warehouse division, supervisor of purchasing and finance manager. This research demonstrates that inventory system performance of PT. Tiga Serangkai Surakarta can be optimized through the determination of inventory policy, applying a model minimum and maximum inventory that considers the safety stock in accordance with service level plan, implementing model Reorder Point (ROP) which can be used as guidelines in charging supply back, and applying the model economic ordering quantity. In doing so, they can save the cost of inventory. Keywords: inventory management, economic order quantity (EOQ), PT. Tiga Serangkai 

scholarly journals Pengendalian Persediaan Bahan Baku Vulkanisir Ban (Studi Kasus: PT. Gunung Pulo Sari)

2016 ◽  
Vol 12 (1) ◽  
pp. 326
Author(s):  
Difana Meilani ◽  
Ryan Eka Saputra
Keyword(s):  
Production Process ◽  
Inventory Management ◽  
Dynamic Method ◽  
Raw Materials ◽  
Minimum Cost ◽  
Raw Material ◽  
Minimum Size ◽  
Safety Stock ◽  
Reorder Point ◽  
Manufacturing Company

The problem of raw materials is the most fundamental issue for a manufacturing company, because the raw material is something that is very important for a production process. Companies must be able to maintain optimal raw material inventory that the production process can run smoothly so as to achieve the production target set by the company and can meet the demand of consumers. PT. Gunung Pulo Sari is one of the manufacturing company engaged in tire retreading. Here there are two types of main raw material of the tire retreading process is the rubber cold rare steak to cook and cook to cook hot rubber. PT. Gunung Sari Pulo do not meet the criteria of good inventory management. So far the company in order raw materials only based on estimates only. We conducted this study in order PT. Gunung Sari Pulo can manage them inventory system by finding the optimum safety stock, determine the total cost of the minimum size of the buyer to use the dynamic method, and the reorder point. Based on the research that has been done then the obtained value of safety stock is 18 units, the total minimum cost is Rp. Rp. 133 991 672, and reordering time (Reorder point) is 93 units.Keywords: Safety Stock, Dynamic Method, Lot Sizing, Reorder Point

scholarly journals Energy Implications of Lot Sizing Decisions in Refrigerated Warehouses

Energies ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1739
Author(s):  
Beatrice Marchi ◽  
Simone Zanoni ◽  
Mohamad Y. Jaber
Keyword(s):  
Inventory Management ◽  
Energy Efficient ◽  
Lot Sizing ◽  
Performance Measure ◽  
Total System ◽  
Order Quantity ◽  
Lot Size ◽  
Surrounding Environment ◽  
Perishable Goods

Cold supply chains (CSCs) are responsible for preserving the quality of perishable goods in storage and transport. They consume significant amounts of energy to maintain cooling temperatures constant over time continuously and ubiquitously, which is affected by the surrounding environment and the users’ behavior. The storage filling level is one specific feature of refrigerated warehouses observed in practice: they are more energy efficient when kept full of items, reducing the space that air occupies. Inventory management models that consider energy consumption have received increasing attention recently due to an increase in stakeholders’ awareness of sustainability. Despite this interest, there is no work that jointly considers the effects of the filling level and the temperature inside the warehouse. This study, therefore, integrates those aspects into the economic order quantity model and finds the optimal lot size quantity that minimizes the total system cost, which is the performance measure used herein. It provides numerical results and brings some insights into the behavior of the model proposed.

Sign in / Sign up

Export Citation Format

Share Document