Model Penentuan Lot Pemesanan Dengan Mempertimbangkan Unit Diskon  dan Batasan Kapasitas Gudang dengan Program Dinamis

The classical model of dynamic programming in determining the economical lot size of orders generally considers the cost of orders and inventory costs. However, firms are often confronted with the situation of determining the number of economic orders if the seller gives incremental discounts to the buyer and limits the warehouse capacity. In this paper, explains the model of determining lot order by considering discount and limitation of warehouse capacity with dynamic program. The dynamic program model is compared with the Economic Order Quantity (EOQ) model considering the discount and the limitation of warehouse capacity. The comparison result shows that dynamic programming model can minimize total inventory cost compared to EOQ.

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MODEL PROGRAM DINAMIS UNTUK LOT SIZE MULTI ITEM DENGAN KENDALA KAPASITAS GUDANG

J TI UNDIP JURNAL TEKNIK INDUSTRI ◽

10.14710/jati.14.1.21-26 ◽

2019 ◽

Vol 14 (1) ◽

pp. 21

Author(s):

Dana Marsetiya Utama

Keyword(s):

Dynamic Programming ◽

Programming Model ◽

Raw Materials ◽

Model Program ◽

Lot Size ◽

Planning Period ◽

Inventory Cost ◽

Proposed Model ◽

Total Inventory ◽

Dynamic Programming Model

Persediaan bahan baku merupakan aktifitas yang penting dalam proses produksi. Pada makalah ini, model mempertimbangkan kuantitas dan periode pemesanan. Dalam model ini, pembeli tunggal membeli beberapa bahan baku dari satu pemasok. Permintaan bahan baku bersifat deterministik dan bervariasi untuk periode waktu. Selain itu, biaya pesan dan biaya simpan untuk periode perencanaan adalah tetap. Kami telah mengembangkan model pemrograman dinamis untuk mengatasi masalah ini. Model pemrograman dinamis ini dikembangkan dari algoritma Wagner-Whitin. Model program dinamis yang diusulkan mempertimbangkan multi item dan kendala kapasitas gudang. Untuk menguji performa dari model, peneliti melakukan beberapa percobaan numerik. Hasil percobaan numerik model pemrograman dinamis usulan menunjukan total biaya persediaan lebih optimal dibandingkan dengan metode EOQ. Hasil percobaan ini menunjukkan model usulan efektif minimasi total biaya persediaan. AbstractInventory of raw materials is an essential activity in the production process. In this paper, the model considers the quantity and order period. In this model, a single buyer buys several raw materials from one supplier. The demand for raw materials is deterministic and varies for a period of time. Besides, the message costs and save costs for the planning period are fixed. We have developed dynamic programming models to overcome this problem. This dynamic programming model was developed from the Wagner-Whitin algorithm. The proposed dynamic program model considers multi items and warehouse capacity constraints. To test the performance of the model, researchers conducted some numerical experiments. The numerical experimental results of the dynamic programming model suggest that the total inventory cost is more optimal compared to the EOQ method. The results of this experiment indicate the proposed model effectively minimizes the total cost of inventory.Keywords: Multi Item; Inventory; Wagner Whitin; Warehouse Constraints; Dynamic Programming

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Economic Order Quantity Model for Minimizing Total Inventory Cost at PT PQR in Indonesia

Advanced Science Letters ◽

10.1166/asl.2015.5982 ◽

2015 ◽

Vol 21 (4) ◽

pp. 1053-1056

Author(s):

Bachtiar H. Simamora

Keyword(s):

Economic Order Quantity ◽

Economic Order ◽

Order Quantity ◽

Inventory Cost ◽

Traditional Practice ◽

Inventory Costs ◽

Eoq Model ◽

Total Inventory

The purpose of this research is to see whether an Economic Order Quantity model can be used to reduce cost of inventory significantly in PT PQR, manufacturer of spring and sponge mattresses in Pekanbaru, Indonesia. The research was conducted on three main materials required in producing spring and sponge mattresses. Using Economic Order Quantity (EOQ) model to analyze historical demand on main materials, it is proven that with EOQ model the company can save by more than 45% from procuring and inventory costs of those materials. The research continues to forecast the sales demand to get the annual requirement of materials needed in 2014 and calculate the EOQ model again. The results show that, comparing with traditional practice done by company, EOQ model can reduce costs up to 118 million rupiah per year.

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Using of EOQ and EPQ Methods in Minimizing Inventory Cost of Crude Palm Oil

ZERO Jurnal Sains Matematika dan Terapan ◽

10.30829/zero.v4i1.7935 ◽

2020 ◽

Vol 4 (1) ◽

pp. 36

Author(s):

Linda Kumala Sari ◽

Sajaratud Dur ◽

Ismail Husein

Keyword(s):

Palm Oil ◽

Crude Palm Oil ◽

Inventory Cost ◽

Inventory Costs ◽

Economic Production Quantity ◽

Economic Production ◽

Production Quantity ◽

Total Inventory ◽

The Difference ◽

The Cost

Excess or lack of inventory that is too large is a problem that can trigger increased costs so that companies do not get the benefits they should. The purpose of this study is to minimize the cost of inventories of crude palm oil using the EOQ (Economic Order Quantity) method and EPQ (Economic Production Quantity) methods at PT. Perkebunan Nusantara IV (Persero) Medan. From the results it is known that economic orders according to the EOQ method in 2017 amounted to 2.741,222 tons and in 2018 amounted to 2.825,927 tons. The difference in total inventory costs generated using the EOQ method and company conditions in 2017 amounted to Rp71.605.439.976,17 and in 2018 amounting to Rp60.884.174.907,3. The optimal amount of production (EPQ) in 2017 and 2018 was 146.226,147 tons. The difference in total inventory costs generated using the EPQ method and the condition of the company in 2017 and 2018 amounted to Rp102.771.704.121,63.

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PENGENDALIAN PERSEDIAAN BAHAN BAKU TEBU DI PG X

Forum Agribisnis ◽

10.29244/fagb.10.2.86-94 ◽

2020 ◽

Vol 10 (2) ◽

pp. 86-94

Author(s):

Nila Kandi ◽

Hendrik Johannes Nadapdap

Keyword(s):

Raw Material ◽

Inventory Cost ◽

Safety Stock ◽

Total Cost ◽

Inventory Costs ◽

Raw Sugar ◽

Total Inventory ◽

Plantation Crops ◽

The Cost ◽

Level Order

Sugarcane is one of the plantation crops which is used as raw material for making sugar. The efficiency of inventory is very important for a sugar factory. The purpose of this study is to determine the order level, order frequency, the amount of safety stock (Safety Stock), re-order points (sugarcane raw material) which is economical and to know the total inventory cost (Total Inventory Cost) of sugarcane raw material economical in PG X. The method of determining the area of this research was carried out intentionally (purposive). The research method uses the descriptive-analytic method. The analytical tool used is Economic Order Quantity (EOQ), Re-Order Points (ROP), Safety Stock (SS), and Total Inventory Cost (TIC). The results of the 2018 and 2019 EOQ calculations show it is not yet economical. The 2018 EOQ calculation was 1.688,79 tons greater than the number of orders made by PG X by 1.483,9 tons and the 2019 EOQ calculation was 3.074 tons greater than the number of bookings made by PG X by 976,6 tons. The value of the safety stock in 2018 amounted to 1.483,9 tons and in 2019 it was 976,6 tons. The value of ROP in the supply of raw sugar cane in 2018 was 2.967,8 tons and in 2019 it was 1.953,2 tons. The 2018 TIC value is Rp. 139.031.870 smaller than the cost of inventory incurred by the company of Rp. 158.302.102 and the 2019 TIC value of Rp. 208.014.632 less than the cost of inventory incurred by the company of Rp. 654.250.185. The results of the last two years calculations indicate the inefficiency of orders made because it causes the frequency of orders is greater and the inventory costs incurred by PG X are higher., so with economic calculations, the order frequency will be less and the total cost of inventory will be lower.

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PENGENDALIAN PERSEDIAAN BARANG DAGANG MENGGUNAKAN METODE ECONOMIC ORDER QUANTITY

Jurnal Bakti Masyarakat Indonesia ◽

10.24912/jbmi.v3i2.10066 ◽

2021 ◽

Vol 3 (2) ◽

Author(s):

Fanny Andriani Setiawan ◽

Margarita Ekadjaja ◽

Yustina Peniyanti

Keyword(s):

Inventory Management ◽

Cost Savings ◽

Economic Order Quantity ◽

Economic Order ◽

Cost Calculation ◽

Order Quantity ◽

Inventory Cost ◽

Inventory Costs ◽

Total Inventory ◽

The Cost

Inventory control can be done by reducing the cost of inventory and the number of ordering frequencies economically. PT Tanjung Globalindo Utama or Toko TODA is an oil and accessory retail store that provides various oil needs. Some of the problems are late delivery of goods from suppliers, so that for several days the company cannot operate optimally. On the other hand, the company has also experienced an excess inventory of merchandise, so the company wastes due to excess inventory of merchandise which in turn increases inventory costs. The Community Service Team (PKM) provides a solution for TODA Stores in overcoming their problems by providing training in inventory management in the Economic Order Quantity (EOQ) method. PKM activities were carried out on May 22, 2020. Participation of partners in the PKM program is to participate in discussions, provide historical data, and convey targets. The output is that the TODA Shop can determine the amount and schedule for the procurement of merchandise economically. The result is that Toko Toda begins to understand the importance of controlling inventory so that inventory costs are not too high. Proposed procedures for purchasing merchandise inventory were received and started to be carried out with monitoring from the relevant PKM Team. Based on the calculation simulation results and discussion shows that the use of the EOQ method in controlling merchandise inventory at Toda Stores is very efficient, seen from the amount of cost savings obtained if the total inventory cost calculation uses the EOQ methodABSTRAK:Pengendalian persediaan dapat dilakukan dengan menekan biaya persediaan dan jumlah frekwensi pemesanan secara ekonomis. PT Tanjung Globalindo Utama atau Toko TODA adalah Toko retail oli dan aksesori yang menyediakan berbagai kebutuhan oli. Beberapa permasalahan yang sering dialami adalah keterlambatan pengiriman barang dari supplier, sehingga selama beberapa hari perusahaan tidak dapat beroperasi maksimal. Disisi lain perusahaan juga pernah mengalami kelebihan persediaan barang dagang, sehingga perusahaan melakukan pemborosan akibat kelebihan persediaan barang dagang yang pada akhirnya meningkatkan biaya persediaan. Tim Pengabdian Kepada Masyarakat (PKM) memberikan solusi untuk Toko TODA dalam mengatasi permasalahannya dengan memberikan pelatihan tata kelola persediaan metode Economic Order Quantity (EOQ). Kegiatan PKM telah dilaksanakan pada tanggal 22 Mei 2020. Partisipasi mitra dalam program PKM adalah ikut serta dalam berdiskusi, memberikan data-data historikal, dan menyampaikan target yang hendak dicapai. Target luaran dari kegiatan PKM ini adalah Toko TODA dapat menentukan jumlah dan jadwal pengadaan barang dagang secara ekonomis. Hasil kegiatan PKM adalah Toko Toda mulai memahami pentingnya pengendalian persediaan barang dagang agar biaya persediaan tidak terlalu besar. Usulan prosedur pembelian persediaan barang dagang diterima dan mulai dijalankan dengan pemantauan dari Tim PKM terkait. Berdasarkan hasil simulasi perhitungan dan diskusi menunjukkan bahwa penggunaan metode EOQ dalam mengendalikan persediaan barang dagang pada Toko Toda sangatlah efisien terlihat dari besarnya penghematan biaya yang diperoleh jika perhitungan total biaya persediaan menggunakan metode EOQ.

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Peranan Internal Audit dalam meningkatkan Efektifitas, Efisiensi, Ekonomis Terhadap Pengendalian Internal Persediaan

Neraca Keuangan : Jurnal Ilmiah Akuntansi dan Keuangan ◽

10.32832/neraca.v13i1.2013 ◽

2018 ◽

Vol 13 (1) ◽

Author(s):

Indupurnahayu . ◽

Dessy Hardiyanti

Keyword(s):

Internal Control ◽

Internal Audit ◽

Internal Controls ◽

Raw Material ◽

Inventory Cost ◽

Inventory Costs ◽

Analysis Technique ◽

Total Inventory ◽

The Cost ◽

Descriptive Method

Inventory is an asset which includes goods belonging to the company with the intention to be sold in a normal business period. Inventories in companies are very vulnerable to theft, embezzlement, damage or loss to the company. This study aims to determine the internal controls applied in the company against inventory and internal audit implementation in improving the effectiveness, efficiency, economical internal control inventory. This research uses descriptive method because this research relates to the object of research that is company with a certain period, by collecting data and information related to the company and tailored to the research objectives. The analysis technique used to analyze data about inventory using the Economic Order Quantity (EOQ) method. This research analyzes Internal Control and Implementation of Internal Audit inventory at PT. Mustika Ratu. Internal Control of PT. Mustika ratu has run well and in accordance with the elements of internal control. PT. Mustika Ratu has complied with the policies and regulations set by the company. Implementation of Internal Audit has been running Effectively, Efficiently, and Economically. Can be seen from the calculation using EOQ method. By using company method, the quantity of Titan Komet Kowet's 3288 raw material purchasing amounted to 5,573 Gram with total inventory cost of Rp. 2.769.780, - and while using the EOQ method Quantity of raw material purchase Titan Komet Kowet 3288 for 5.932 with inventory cost of Rp. 2,764,386, -. meaning the company can save inventory costs of Rp. 5.394, - By using company method Quantity of purchase of raw material Talk Mesh 325 amounted to 8,574 Gram with total cost of inventory equal to Rp. 3.056.223, - while using EOQ method Quantity purchase of raw material of mesh 325 mesh with 7648 with inventory cost of Rp. 3.056.385, -. meaning the company can save the cost of Rp. 19.838,-

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Analisis Pengendalian Persediaan Bahan Baku dengan Menerapkan Metode EOQ (Economic Order Quantity) pada PT. Jatisari Furniture Work

EKONOMIS Journal of Economics and Business ◽

10.33087/ekonomis.v5i1.304 ◽

2021 ◽

Vol 5 (1) ◽

pp. 215

Author(s):

Arga Sutrisna ◽

Rizki Ginanjar ◽

Suci Putri Lestari

Keyword(s):

Production Costs ◽

Raw Material ◽

Economic Order Quantity ◽

Economic Order ◽

Analysis Tool ◽

Order Quantity ◽

Inventory Cost ◽

Total Cost ◽

Inventory Costs ◽

Total Inventory

This research objectives aims to determine and analyze raw material inventory control, the ideal raw material inventory that the company must provide and the efficiency of production costs carried out by Jatisri Furniture Work in Tasikmalaya for the period 2018.11 – 2020.02. The data collection method in this study is by direct observation at Jatisari Furniture Work in Tasikmalaya. Using techniques such us interviews, observation, and documentation. These observations were made in production reports for the years 2018 – 2020. The analysis tool was carried out using the Economic Order Quantity (EOQ) method such us safety stock, reorder point, and total inventory cost. The result of the Economic Order Quantity (EOQ) analysis show that the total cost of raw the material inventory that must be incurred by the company is greater than the total cost of inventories calculated according to the EOQ method. Companies should follow the calculations from the EOQ method so that they can save on raw material inventory costs, so that production costs are more efficient.

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An Optimization Approach to the Low-Frequency Entire Train Formation at the Loading Area

Sustainability ◽

10.3390/su11195500 ◽

2019 ◽

Vol 11 (19) ◽

pp. 5500

Author(s):

Lin ◽

Yang ◽

Zuo ◽

Liu ◽

Zhao ◽

...

Keyword(s):

Programming Model ◽

Low Frequency ◽

Transportation Systems ◽

Optimal Operation ◽

Optimization Approach ◽

Inventory Cost ◽

Eoq Model ◽

Railway Industry ◽

Pros And Cons ◽

Using Data

It is well known that the shift of transporting bulk cargo from roads to railways is an important measure to reduce carbon emissions of the overall transportation systems. In order to increase the attractiveness of railway transport, companies usually provide some discounts to the customers with great transport demand so that entire trains can be operated. Since the operation of entire trains can reduce the reclassification times of shipments, the expenses of railway operations can be reduced. However, when the volume of shipment is not sufficient, the door-to-door direct transportation (in the railway industry specifically, “door-to-door” means running trains from supplier’s warehouse to customer’s warehouse) of the entire train often leads to a decrease in the frequency of delivery, which increases the average stock of users, thus increasing the inventory cost of users. Therefore, how to balance the pros and cons of the two is exactly the problem to be studied. In this paper, the optimal operation plan is obtained by minimizing the total cost of the stockholding of suppliers and customers, as well as the transportation costs of an entire train and non-direct train. Based on the classic economic order quantity (EOQ) model, a 0-1 integer programming model with the constraint of the maximum stock level is proposed to solve this problem. And an innovative approach is used to calculate the actual average stock of the customer. Finally, the model is validated and its effectiveness is confirmed using a real-world case, which is carried out using data from the China rail system.

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Simulation-Based Optimization of a Two-Echelon Continuous Review Inventory Model with Lot Size-Dependent Lead Time

Processes ◽

10.3390/pr8091014 ◽

2020 ◽

Vol 8 (9) ◽

pp. 1014

Author(s):

Ibrahim Alharkan ◽

Mustafa Saleh ◽

Mageed Ghaleb ◽

Abdulsalam Farhan ◽

Ahmed Badwelan

Keyword(s):

Supply Chain ◽

Lead Time ◽

Shop Floor ◽

Lot Size ◽

Continuous Review ◽

Inventory Costs ◽

Size Dependent ◽

Simulation Based ◽

Simulation Based Optimization ◽

Total Inventory

This study analyzes a stochastic continuous review inventory system (Q,r) using a simulation-based optimization model. The lead time depends on lot size, unit production time, setup time, and a shop floor factor that represents moving, waiting, and lot size inspection times. A simulation-based model is proposed for optimizing order quantity (Q) and reorder point (r) that minimize the total inventory costs (holding, backlogging, and ordering costs) in a two-echelon supply chain, which consists of two identical retailers, a distributor, and a supplier. The simulation model is created with Arena software and validated using an analytical model. The model is interfaced with the OptQuest optimization tool, which is embedded in the Arena software, to search for the least cost lot sizes and reorder points. The proposed model is designed for general demand distributions that are too complex to be solved analytically. Hence, for the first time, the present study considers the stochastic inventory continuous review policy (Q,r) in a two-echelon supply chain system with lot size-dependent lead time L(Q). An experimental study is conducted, and results are provided to assess the developed model. Results show that the optimized Q and r for different distributions of daily demand are not the same even if the associated total inventory costs are close to each other.

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

E-Jurnal Manajemen Universitas Udayana ◽

10.24843/ejmunud.2020.v09.i02.p02 ◽

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

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