M.Sc. Engg.http://hdl.handle.net/20.500.12228/662024-03-29T12:09:31Z2024-03-29T12:09:31ZOptimization of Investment Casting Parameters to Improve the Mechanical Properties by Taguchi MethodMondal, Nil Ratanhttp://hdl.handle.net/20.500.12228/8342020-02-27T21:00:16Z2019-12-01T00:00:00ZOptimization of Investment Casting Parameters to Improve the Mechanical Properties by Taguchi Method
Mondal, Nil Ratan
In this present study investment casting process parameter is optimized by using Taguchi approach to improve the mechanical properties of mild steel. A set of experiments were conducted as per Taguchi's L9 orthogonal array to determine the most influential control factors, which will provide better and consistent for optimization to the casting's process parameters regardless of the noise factors present. For test the performance characteristics, orthogonal range, signal to noise ratio and variance analysis were used. Data values are obtained under the constraint of different process parameters like preheat temperature, pouring temperature, preheat time to investigate their effects on the surface hardness, tensile strength of the final results. The variations in the trend of the mechanical properties were observed and it was deduced out that high mold preheat temperature, higher pouring temperature, maximum preheat time significantly reduce the mechanical properties of castings produced by Taguchi method.
This thesis is submitted to the Department of Industrial Engineering and Management, Khulna University of Engineering & Technology in partial fulfillment of the requirements for the degree of Master of Science in Engineering in Industrial Engineering and Management, December 2019.; Cataloged from PDF Version of Thesis.; Includes bibliographical references (pages 34-37).
2019-12-01T00:00:00ZModeling and Analysis of Labour Cost Estimation for Ship Repairing: A Case Study in Chittagong Dry Dock LimitedKarim, Mohammad Sajedulhttp://hdl.handle.net/20.500.12228/8292020-02-26T21:00:15Z2019-12-01T00:00:00ZModeling and Analysis of Labour Cost Estimation for Ship Repairing: A Case Study in Chittagong Dry Dock Limited
Karim, Mohammad Sajedul
With the increase of international trade activities through sea and resulting exponential growth of number of ships calling on coastal nations’ ports, ship repair is becoming an increasingly attractive opportunity for littoral countries. Being a coastal nation, there were rapid growth of number of local shipyards in Bangladesh for past couple of years. This factor put CDDL faced with tremendous competition in ship repair arena in the national market. Besides, docking of ships and ship repairing work, are, by nature labor intensive. Labour cost contributes significantly to total repair cost. Besides acquiring market information, CDDL must estimate labor cost accurately to give competitive quotations in order to obtain ship repair orders. Lower labour cost value allow shipyards and ship owners to get higher productivity and lower final invoice respectively.
Forecasting estimated labor cost will allow CDDL to stay competitive among the ship repair
industries. In this project paper, attempt has been made to identify the number of those independent variables that influence ship repairing labour (dependent variable) and their inter-relationship. Since labor cost for ship repair can be expressed as a function of ship’s age, deadweight, displacement, type of ship and various repair works, so a multiple linear regression model is developed to construct a labor cost estimation model. From 2002 to 2019, ship repairing labour (man-days) related information for 43 sets for fishing vessel, 30 sets for oil tanker, 51 sets for multipurpose cargo ship, 40 sets for warship, 11 sets for dredger/barge and 15 sets for tugboat of various ages, sizes and types were collected from data storage of CDDL to construct models for each ship group. Regression coefficients are found out by applying “Method of Least Squares” in regression analysis. CDDL can use this mathematical model as a guiding tool to forecast labour cost estimates more realistically for ships to be under repair.
This thesis is submitted to the Department of Industrial Engineering and Management, Khulna University of Engineering & Technology in partial fulfillment of the requirements for the degree of Master of Science in Industrial Engineering and Management, December 2019.; Cataloged from PDF Version of Thesis.; Includes bibliographical references (pages 84-88).
2019-12-01T00:00:00ZDevelopment of an Optimal Inventory Management System in Khulna Shipyard Limited- A Case StudyUzzaman, Md. Safiqhttp://hdl.handle.net/20.500.12228/8282020-02-26T21:00:12Z2019-12-01T00:00:00ZDevelopment of an Optimal Inventory Management System in Khulna Shipyard Limited- A Case Study
Uzzaman, Md. Safiq
Inventory, the key component of any organization is the stock of any goods or asset that are required for manufacturing or assembly of the product to maintain the plant. The fundamental function of an inventory system is to keep track of and maintain the inventory levels, determine both the order size and replenishing period. Inventory is directly related with the manufacturing cost. As a result, Inventories influence the most essential portion of current resources of a greater numbers of companies. Thus, sufficient amount of capital is tied up due to maintaining the inventories in bulk by the organization. Poor inventory management may cause under-stocking or over-stocking including higher operating cost of the items. Thus, a firm ignoring the control and monitoring of inventories might be at risk of its ultimate profitability and may collapse in the long run. As a result, it is clearly necessary to manage inventories effectively and properly for the avoidance of unnecessary investment.
In the study it was found that Khulna Shipyard Limited frequently fails to maintain inventory level/ stock for the regular consumption of raw materials to meet the lead time of the demand. Demand for replenishment of inventory items are placed when it is required. The shipyard follows the traditional method of purchasing the raw materials and other items. As a result, the shipyard is unable to maintain delivery schedule of the project due to shortages of required materials and also due to the late delivery of proper materials from the suppliers. On the contrary, the plant also faces over stocking of materials in the warehouse. Both these situations act as a catalyst to increase the total inventory expenditure of the shipyard. Besides, the workers have to work in extra time (overtime) to finish the job quickly. Ultimately, the shipyard can not maintain the desire quality of the finished product and production cost also increases. As the ship cannot undock within the schedule time and the construction yard is engaged, the shipyard cannot dock the ship under pipeline within predetermined schedule. As a result, customer dissatisfaction may raise due to inferior quality, late delivery, failure to dock and high production cost of ships/ product. Moreover, this shipyard may lose their customer day by day. Thus the above discussion stated that, there is a room for improvement
to identify the procedure of managing and maintaining inventory at khulna shipyard limited. One of the most important goals in inventory management decision is how much inventory should be made and when to submit an order. If a firm procures higher quantities of inventory, carrying cost also increases. On the other hand, if the firm purchases less quantities, more orders to be placed which increases ordering cost. Therefore, the order quantity at a particular time should be controlled by balancing the ordering and carrying cost. Considering both the costs, EOQ model is applied to decide the optimal order quantity to be replenished at a specific order time for the optimization of carrying and ordering cost and also confirming the availability of material when required. In addition, ROP model provides information when to order the item. Safety stock policy can be adopted for providing protection against the variation and uncertainty in both lead time and demand.
It was observed that managing inventory at ship construction and repairs industry is more complicated due to the distinctive and uncertainty nature of demand. In this thesis, a sample for inventory items from a major workshop of khulna shipyard limited was identified and demand data for these items was collected. Accordingly, required data for cost calculation was gathered to implement EOQ, ROP and safety stock for the selected inventory items. Finally, the thesis work has been completed with several specific recommendations for the management of Khulna Shipyard Limited and suggestions for carrying out future research.
This thesis is submitted to the Department of Industrial Engineering and Management, Khulna University of Engineering & Technology in partial fulfillment of the requirements for the degree of Master of Science in Engineering in Industrial Engineering and Management, December 2019.; Cataloged from PDF Version of Thesis.; Includes bibliographical references (pages 46-47).
2019-12-01T00:00:00ZDevelopment of a Model to Optimize the Supply Chain Management and it's ApplicationAmin, Md. Alhttp://hdl.handle.net/20.500.12228/7702020-02-10T21:00:13Z2019-12-01T00:00:00ZDevelopment of a Model to Optimize the Supply Chain Management and it's Application
Amin, Md. Al
The mam objective of this research is to develop a mathematical model for supply chain
transportation costs. This model consider the real time data of the transportation cost incurring
elements which helps in achieving optimization. Though it has been case studied for a particular
company but it's been generalized for all aspects of supply chain network under some specific
conditions. In this research Theory of Constraint (TOC) has been applied to identify the main
constraints to its goal. The main constraint are found supply chain transportation cost which
significantly impact on supply chain profit. Thinking process has been developed to propose a
conceptual model regarding the constraints. The case study has been performed for 30 days and
found 32.68% better results for one complete transportation cycle compared to existing
transportation modes. The ways the model optimize the transportation cost by managing vehicle
route, fleet size and number of moves throughout the transportation network. Finally, this model
offering significant results in throughput accounting of supply chain transportation that leads to
optimize overall supply chain costs.
This thesis is submitted to the Department of Industrial Engineering and Management, Khulna University of Engineering & Technology in partial fulfillment of the requirements for the degree of Master of Science in Engineering in Industrial Engineering and Management, December 2019.; Cataloged from PDF Version of Thesis.; Includes bibliographical references (pages 31-34).
2019-12-01T00:00:00Z