This is to confirm that the thesis entitled "Development of Warehouse Storage Allocation Models" submitted by Syed Ariftul Islam has been approved by the Partial Fulfillment Committee for the Degree of Master of Science in Engineering, Department of Industrial Engineering and Management, Khulna University of Engineering & Technology, Khulna, Bangladesh December 2011. Finally, I am thankful to all the teachers of the Department of Industrial Engineering and Management, Khulna University of Engineering and Technology, Khulna-920300 , Bangladesh for their kind cooperation at various times whenever I needed. The aim of the experiment is to investigate the performance of the methodology described in the previous chapter in terms of the distance traveled to collect all elements of demand.
The details of the experiment and the results of the experiment are presented in Chapter 4. The performance of the algorithm is evaluated against the average travel distance needed to collect an order at the SPS.
List of Image
Definition
A warehouse is a large building where goods are stored and where they can be catalogued, shipped or received, depending on the type. A distribution warehouse is a warehouse in which products from different suppliers are collected (and sometimes assembled) for delivery to a number of customers. A production warehouse is used for the storage of raw materials, semi-finished products and finished products in a production facility.
The maintenance environment warehouse is very similar to the production warehouse where spare parts are stored and received. In such an environment, the allocation of space and the allocation of spare parts in a warehouse is a vital problem for the healthy operation of a warehouse.
Objective of the Study
This problem causes additional time consumption and money expenditure for long time labor involvement and creates the risk of unavailability of spare parts leading to wrong maintenance or repair of machines. As a result, it will create problems in issuing/retrieving spare parts with minimal waste of time and effort.
Organization of the project work
Storage I
SKU-
Receiving and Shipping
- Assigning SKUs across departments
- Storage Location Assignment
Allocation and allocation of material handling resources, such as material handling labor and equipment. Therefore, a careful decision must be made in order to balance the trade-off between cost and material storage and handling capacities. The costs in their model include the equipment cost of the quick pick area (modeled as a linear function of its size) and the material handling cost of receiving and replenishing orders.] It is common practice in the warehouse to create a physically separate compact Front area (or "quick pick") for picking high-demand, fast-moving products.
This reduces order picking costs, but at the cost of additional material handling to replenish the forward area of a reserve area, and additional space as storage is less efficient in the forward area than in the reserve area. The Storage Location Assignment Problem (SLAP) is to assign incoming products to storage locations in storage sections/zones to reduce material handling costs and improve space utilization.
HUALIEN PORT
Storage Location Assignment Problem based on Item Information (SLAP/il) In the SLAP/I1 problem, it is assumed that complete information is known about the arrival
The optimal solution to this problem for typical storage operations is computationally impractical due to the very large instances of the problem. An example of a SLAP/IT heuristic policy is the Duration of Stay (DOS) policy of Goetschalckx and Ratliff. In DOS-based policies, the expected DOS of the ith unit of a SKU with replenishment lot size Q is i/k for i = 1, 2.
Then the items of all the different products with the shortest DOS are assigned to the nearest locations. Consequently, the items from a single replenishment group of a single product may not be stored together in the warehouse.
Storage Location Assignment Problem based on Product Information (SLAP/PI)
The implementation of the above policies depends on the types of storage systems and can therefore have different variations, for example:. Since each unit load occupies the same amount of storage space, the popularity policy based on the distributed popularity is essentially the same as the COI policy. So the popularity policy based on the distributed popularity will now rank product B ahead of product Al, A2 and A3, which can be easily verified to match the COI policy.
This leads to the so-called organ pipe storage location allocation, for example see Jarvis and McDowell. The implementation of class-based warehousing (ie, the number of classes, the distribution of products into classes, and the storage locations for each class) has a significant impact on the required storage space and material handling costs in the warehouse.
Storage Location Assignment Problem based on No Information (SLAP/NI)
Product weight is taken into account and the objective is to minimize the work (a function of weight and distance) involved in order picking. Random, dedicated, and class-based storage are three popular storage strategies used, and each has its own advantages and disadvantages. For dedicated and class-based storage, implementation involves assigning products/classes to the storage location.
The COT policy has been extensively studied in the literature and is considered more effective than the other two policies. In class-based storage, additional decisions are determining the number of classes and assigning products to classes. Current results on these decisions are mainly focused on AS/RS and need to be further developed for other storage technologies.
All of the above research on SLAP assumes that replenishment lot sizes are specified for the SKUs. However, Wilson demonstrates that the lot size problem and SLAP should be considered simultaneously to obtain an optimal total cost including both inventory costs and material handling costs. The version of the SLAP problem studied in the literature is most often static, that is, it assumes that the input and output material flow patterns are stationary over the planning horizon.
Another type of move may occur due to the uncertainty of incoming shipments. It may happen that none of the zones have enough space to receive an incoming shipment. With class-based storage, additional decisions include determining the number of classes and assigning products to classes.
Order picking
- Batching
- Sorting
Jaikumar and Solomon Determine the elements to move Optimal ranking and their destinations with the algorithm. objective of finding the minimum number of moves that results in a throughput meeting the throughput requirement in the following busy periods Determine the move schedule Rule of thumb procedure in relation to the dynamically based on cluster changing order structure, i.e. techniques. In creating an abstract statement of the problem, there are potentially two levels of division. Dividing the orders among the pickers is a variation of the classic Vehicle Routing Problem (VRP), where "stops" are assigned to routes and the objective is to minimize the total route distance or time.
However, in the order batch problem, assigning an order to a picker's route means that all pick locations for the SKUs in this order are assigned to that route. In the order partitioning problem, there may be many stops (SKUs) associated with a single service request (order), but there are no priority constraints. The TSP in the warehouse is special because of the aisle structure of the possible train paths.
Gudehus describes the band heuristic, which divides the rack into two horizontal bands of equal height; the points in the lower band are visited in the increasing x-coordinate direction, while the points in the upper band are visited in the opposite direction. The algorithm constructs the convex hull of all the picking locations, then those free insertion locations for each segment of the convex hull are identified and inserted into the convex hull, and then the remaining points are sequentially inserted into the tour in a way that the increase in tour length for each insertion. They are placed on the recirculation conveyor through an induction point after the items in the previous pick wave have completed their sorting process (in some cases the items are allowed to enter the recirculation conveyor before the previous wave has completely finished sorting).
Items circulate on the recirculation belt and enter the assigned sorting lane when all items from the previous order assigned to that lane have been sorted. Furthermore, due to the limited and narrow travel paths in a warehouse, another relevant variant of the sequencing and routing problem would consider congestion when multiple picking rounds are performed simultaneously in the same area. The aim of the current research work is to explore the possibility of identifying similar items from past demand and storing them in the same place so that order picking becomes easier in terms of travel distance.
The Problem Environment
Methodology
- Identifying sparc_part_set
- Calculation of the Weight(popularity) of a spare_part_set
- Assignment of spare_part_set to Shelves
The Demand_set is the set of spare parts required for i-th maintenance in time period t and. This weight is used to identify a spare parts set as fast moving or slow moving. Generally, the fast-moving items are kept close to the dispensing counter, unlike the slow-moving items.
Since fast-moving items are used more often, a simple way to determine weight can be the annual frequency of use of all items in a spare_group. It is equal to the total number of all items issued/used in each spare_parts group per year.
Arrange the shelf number in ascending order of distance. Name this list as A
- Traveling Distance Calculation
- Experimental Design
- Sample Calculation of Travelling Distance
- Experimental Results
The parts required for a specific maintenance type are called spare_part_set and the total number of parts in the set varied from 4 to 8 per year. The demand of a part for a particular maintenance job is random and varies from 2 to 10 per year. The weight of a parts set (SPS) is the sum of all frequencies of uses in the question set which is also shown in table 4.1.
The random number generation scheme for selecting spare parts required for a given type of maintenance is shown in Table 4.3 to Table 4.9. For each experiment the travel distance to collect all items for both arrangements is calculated and summarized in Table 4.14. After 100 number of experiments, it can be seen from figure 4.10 and table 4.18 that the average distance traveled for the whole system becomes almost stable.
The cumulative value of the average No-i for the original setup in Figure 4.7 shows that the maximum travel distance is 43 and the minimum travel distance is 37.
