OPTIMAL REPLENISHMENT POLICY FOR AN INTEGRATED SUPPLIER–BUYER DETERIORATING INVENTORY MODEL CONSIDERING MULTIPLE JIT DELIVERY AND OTHER COST FUNCTIONS

2007 ◽  
Vol 24 (01) ◽  
pp. 125-145 ◽  
Author(s):  
CHUN-JEN CHUNG ◽  
HUI-MING WEE
Keyword(s):  
Storage Time ◽  
Transportation Cost ◽  
Inventory Model ◽  
Inventory Level ◽  
Rigorous Analysis ◽  
Factors Affecting ◽  
Inspection Cost ◽  
Replenishment Policy ◽  
The Cost ◽  
The Relationship

This study develops an integrated deteriorating inventory policy for a single-buyer–single-supplier model with multiple JIT deliveries considering the transportation cost, inspection cost and the cost of less flexibility. Distinct from the former concept of average inventory level, our paper proposes a significantly different approach to deal with the first production batch and uses a revised method to approximate the relationship between the supplier's production time and the storage time. We provide a rigorous analysis to derive the number of inspection and deliveries, the optimal cycle time of deliveries, and the delivery size for the replenishment policy of the integrated buyer–supplier inventory deteriorating model. It is shown that the unit inspection cost is one of the critical factors affecting the deteriorating inventory model. A numerical example is presented to illustrate the theory.

scholarly journals Filtering and predicting the cost of hidden perished items in an inventory model

2002 ◽  
Vol 15 (3) ◽  
pp. 235-245
Author(s):  
Lakhdar Aggoun ◽  
Lakdere Benkherouf
Keyword(s):  
Joint Distribution ◽  
Inventory Model ◽  
The State ◽  
Inventory Level ◽  
Discrete State ◽  
History Of ◽  
Accumulated Losses ◽  
The Cost ◽  
State Of The Environment ◽  
Recursive Estimators

This paper is concerned with a discrete time, discrete state inventory model for items of changing quality. Items are assumed to be in one of a finite number, M, of quality classes that are ordered in such a way that Class 1 contains the best quality and the last class contains the pre-perishable quality. The changes of items' quality are dependent on the state of the ambient environment. Furthermore, at each epoch time, items of different classes may be sold or moved to a lower quality class or stay in the same class. These items are priced according to their quality, and costs are incurred as items lose quality. Based on observing the history of the inventory level and prices, we propose recursive estimators as well as predictors for the joint distribution of the accumulated losses and the state of the environment.

scholarly journals FACTORS AFFECTING THE THICKNESS OF REPLACEMENT LAYER ON MEDIUM CLAY

2021 ◽  
Vol 11 (4) ◽  
pp. 232-245
Author(s):  
Manar Abd Elhamid ◽  
Tarek Abdelaziz ◽  
Hesham Bassioni
Keyword(s):  
Bearing Capacity ◽  
Research Problem ◽  
Total Direct Cost ◽  
Factors Affecting ◽  
Consolidation Settlement ◽  
Common Technique ◽  
Optimum Type ◽  
Design Requirements ◽  
The Cost ◽  
The Relationship

Soil replacement is a common technique that can be used to increase the soil bearing capacity and reduce the expected settlement. The thickness of replacement layer depends on many factors such as: the applied stress, original soil properties, material of replacement layer and the cost of foundation works. However, until now the practical thickness of replacement is usually selected based on soil experts’ experience. This study proposed an optimization model to assist geotechnical engineers in predicting the optimum thickness and material type of replacement layer that satisfy the main design requirements, i.e. bearing capacity, consolidation settlement and cost considerations at the same time. The Evolutionary solving method that uses a variety of genetic algorithm and local search methods was used to solve the research problem. Furthermore, the effect of the thickness and properties of clay layer and the depth of ground water table on determining optimum type and thickness of replacement soil were investigated. The study evaluated the relationship between the replacement layer thickness and the total direct cost of foundation works and found that, the notion of increasing replacement thickness to decrease cost limitlessly was not viable and an optimal thickness was usually achieved.

scholarly journals A weak convergence approach to inventory control using a long-term average criterion

2018 ◽  
Vol 50 (4) ◽  
pp. 1032-1074 ◽  
Author(s):  
K. L. Helmes ◽  
R. H. Stockbridge ◽  
C. Zhu
Keyword(s):  
Brownian Motion ◽  
Weak Convergence ◽  
Inventory Control ◽  
Linear Equations ◽  
Auxiliary Function ◽  
Inventory Model ◽  
Inventory Level ◽  
Function Of Two Variables ◽  
The Cost

Abstract In this paper we continue the examination of inventory control in which the inventory is modeled by a diffusion process and a long-term average cost criterion is used to make decisions. The class of such models under consideration has general drift and diffusion coefficients, and boundary points that are consistent with the notion that demand should tend to reduce the inventory level. The conditions on the cost functions are greatly relaxed from those in Helmes et al. (2017). Characterization of the cost of a general (s, S) policy as a function of two variables naturally leads to a nonlinear optimization problem over the ordering levels s and S. Existence of an optimizing pair (s*, S*) is established for these models under very weak conditions; nonexistence of an optimizing pair is also discussed. Using average expected occupation and ordering measures and weak convergence arguments, weak conditions are given for the optimality of the (s*, S*) ordering policy in the general class of admissible policies. The analysis involves an auxiliary function that is globally C2 and which, together with the infimal cost, solves a particular system of linear equations and inequalities related to but different from the long-term average Hamilton‒Jacobi‒Bellman equation. This approach provides an analytical solution to the problem rather than a solution involving intricate analysis of the stochastic processes. The range of applicability of these results is illustrated on a drifted Brownian motion inventory model, both unconstrained and reflected, and on a geometric Brownian motion inventory model under two different cost structures.

scholarly journals Optimal Buyer’s Replenishment Policy in the Integrated Inventory Model for Imperfect Items

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Lu Yueli ◽  
Mo Jiangtao ◽  
Wei Yucheng
Keyword(s):  
Inventory Model ◽  
Computational Method ◽  
Imperfect Quality ◽  
Imperfect Items ◽  
Unrealistic Assumption ◽  
Replenishment Policy ◽  
Demand Rate ◽  
Classical Economic ◽  
The Cost ◽  
Optimal Ordering

In the classical economic order quantity (EOQ) models, a common unrealistic assumption is that all the items received are of good quality. However, in realistic environment, a received shipment usually contains a fraction of imperfect quality items. These imperfect items may be scrapped, reworked at a cost, or salvaged at a discounted price. While the percentage of imperfect items is random, the optimal ordering cycle is rarely considered in current literatures. This paper revisits the model (Maddah and Jaber, 2008) and extends it by assuming that the ordering cycle is determined by the demand rate, delivery quantity per shipment, and the mathematical expectation of the defective rate. The possibility of stockout or residue in the end of a cycle will be considered, and the loss of stockout and the salvage of the residue are counted into the cost. Besides, we consider consolidating the shipments of imperfect items over multiple deliveries. Thus, an integrated vendor-buyer inventory model for imperfect quality items with equal-size shipment policy is established to derive the optimal ordering cycle, ordering quantity, and number of deliveries. The computational method of the optimal delivery quantity per shipment and number of deliveries is given through theoretical results. Finally, sensitivity of main parameters is analyzed through simulation experiments and shown by some figures.

scholarly journals Effect of bond administration on construction project delivery

2016 ◽  
Vol 8 (1) ◽  
pp. 1390-1396 ◽  
Author(s):  
Ayodeji Emmanuel Oke
Keyword(s):  
Project Success ◽  
Construction Project ◽  
Project Delivery ◽  
Building Projects ◽  
Factors Affecting ◽  
Bond Issues ◽  
The Cost ◽  
The Relationship ◽  
Pro Forma ◽  
Best Fit

Abstract Construction bond administration involves management of bond issues from inception of obtaining bond from guarantor to the point of release of contractor by the client. This process has posted a lot of challenges to construction stakeholders; it is therefore, necessary to examine the relationship between bond administration and project success. Archival data of completed bonded building projects were gathered through a pro forma developed for this purpose. Using Pearson product moment of correlation, it was revealed that the cost of securing a construction bond has a positive and significant effect on the initial and final costs of the project, while the number of days needed to secure a construction bond has no significant effect on the initial and final durations of the construction project. In order to establish the relationship between project delivery indices of cost and time and the construction bond administration variables, iteration of linear regression was adopted to arrive at the best-fit equation. Factors affecting the cost of securing construction bonds from guarantors should be identified and given adequate attention by construction stakeholders in order to minimize the effect of construction bond administration on project delivery.

The Awareness Level of the Safety and Health of the Operational Level

2017 ◽  
Vol 3 (1) ◽  
pp. 42
Author(s):  
Roshanira Che Mohd Noor ◽  
Nur Atiqah Rochin Demong
Keyword(s):  
Health And Safety ◽  
Health Conditions ◽  
Effective Strategies ◽  
Operational Level ◽  
Safety And Health ◽  
Health Factors ◽  
The Cost ◽  
The Relationship ◽  
Awareness Level

Providing a safe and healthy workplace is one of the most effective strategies in for holding down the cost of doing construction business. It was a part of the overall management system to facilitate themanagement of the occupational health and safety risk that are associated with the business of the organization. Factors affected the awareness level inclusive of safety and health conditions, dangerous working area, long wait care and services and lack of emergency communication werethe contributed factors to the awareness level for the operational level. Total of 122 incidents happened at Telekom Malaysia Berhad as compared to year 2015 only 86 cases. Thus, the main objective of this study was to determine the relationship between safety and health factors and the awareness level among operational workers.The determination of this research was to increase the awareness level among the operational level workerswho committing to safety and health environment.

OPTIMAL FEASIBLE SOLUTIONS TO A ROAD FREIGHT TRANSPORTATION PROBLEM

2020 ◽  
Vol 5 (1) ◽  
pp. 456
Author(s):  
Tolulope Latunde ◽  
Joseph Oluwaseun Richard ◽  
Opeyemi Odunayo Esan ◽  
Damilola Deborah Dare
Keyword(s):  
Transportation Problem ◽  
Optimal Solution ◽  
Transportation Cost ◽  
North West ◽  
Life Problems ◽  
Basic Feasible Solutions ◽  
Feasible Solutions ◽  
Road Freight Transportation ◽  
The Cost ◽  
Cost Of Transportation

For twenty decades, there is a visible ever forward advancement in the technology of mobility, vehicles and transportation system in general. However, there is no "cure-all" remedy ideal enough to solve all life problems but mathematics has proven that if the problem can be determined, it is most likely solvable. New methods and applications will keep coming to making sure that life problems will be solved faster and easier. This study is to adopt a mathematical transportation problem in the Coca-Cola company aiming to help the logistics department manager of the Asejire and Ikeja plant to decide on how to distribute demand by the customers and at the same time, minimize the cost of transportation. Here, different algorithms are used and compared to generate an optimal solution, namely; North West Corner Method (NWC), Least Cost Method (LCM) and Vogel’s Approximation Method (VAM). The transportation model type in this work is the Linear Programming as the problems are represented in tables and results are compared with the result obtained on Maple 18 software. The study shows various ways in which the initial basic feasible solutions to the problem can be obtained where the best method that saves the highest percentage of transportation cost with for this problem is the NWC. The NWC produces the optimal transportation cost which is 517,040 units.

The number of employed as a macroeconomic indicator of working time dynamics

2020 ◽  
Vol 16 (5) ◽  
pp. 935-945
Author(s):  
I.A. Zaikova
Keyword(s):  
Comparative Analysis ◽  
Manufacturing Sector ◽  
Working Hours ◽  
Working Time ◽  
Labor Costs ◽  
Factors Affecting ◽  
Time Dynamics ◽  
Developed Economies ◽  
The Relationship ◽  
Macroeconomic Indicator

Subject. The working time of workers at any stage of economic development is a value reflecting the level of labor productivity. Any progress in productivity contributes to changes in the volume of labor costs and the number of employed. Depending on the relationship between the total volume of labor costs and the number of employed, the duration of working time per one worker may change (it may increase, decrease, or remain unchanged). Objectives. The study aims to confirm the importance of such a macroeconomic indicator as the number of employed in varying working hours. Methods. The study rests on the comparative analysis of countries with developed economies based on some indicators like dynamics of the working time fund, dynamics of the number of employed, average number of hours worked during the year per employee, etc. The analyzed timespan is 25 years (from 1991 to 2016). Results. The comparative analysis revealed that in the non-production sphere and the economy as a whole the macroeconomic determinants correlate so that the length of working time per worker reduces. When considering the analysis results for the manufacturing sector, no single trend was identified. Conclusions. One of the key factors affecting the change in working hours is the number of employed. The relationship between the working time fund and the number of employed directly determines the dynamics of working time per worker.

The Sterility of Reusable Surgical Instruments with Pouches Packaging on One of the Private Hospital in Bandung

2017 ◽  
Vol 8 (2) ◽  
Author(s):  
Kurniawansyah I. S. ◽  
Mita S. R. ◽  
Najla E. ◽  
Nindayani E.
Keyword(s):  
Storage Time ◽  
Private Hospital ◽  
Surgical Instruments ◽  
Healthcare Associated Infection ◽  
Sterility Testing ◽  
Reusable Instruments ◽  
Healthcare Associated ◽  
The Relationship ◽  
Common Infection ◽  
Long Storage

Healthcare associated infection is one of the common infection that happens in Indonesia. One form control to prevent healthcare associated infection is the sterilization process of the materials and medical instruments that used for taking care of patients. At the private hospital whereas a place of research, there’s never been done the study of sterility test for reusable instrument with pouches, based on previous studies showed that 8 sets from 40 sets of reusable instrument with linen were not sterile moreover there were positively influence from the amount of time to the sterility of reusable instrument. The purpose of these studies was to determining the relationship between a long storage time and the sterility of reusable instruments with pouches. The method that used in this study was the sterility testing of reusable instrument with pouches which were stored in a central operations room storage with a long storage time of 1 and 2 months. From 30 reusable instruments with pouches which were stored for nine months there were 5 instruments were not sterile. The results of statistic analysis showed that the amount of storage time not significantly associated to the sterility of reusable instrument with pouches in the operating room central storage space.

Sign in / Sign up

Export Citation Format

Share Document