an evolutionary approach for the offsetting inventory cycle problem

AbstractIn inventory management, a fundamental issue is the rational use of required space. Among the numerous techniques adopted, an important role is played by the determination of the replenishment cycle offsetting which minimizes the warehouse space within a considered time horizon. The NP-completeness of the Offsetting Inventory Cycle Problem (OICP) has led the researchers towards the development and the comparison of specific heuristics. We propose and implement a genetic algorithm for the OICP, whose effectiveness is validated by comparing its solutions with those found by a mixed integer programming model. The algorithm, tested on realistic instances, shows a high reduction of the maximum space and a more regular warehouse saturation with negligible increase of the total cost. This paper, unlike other papers currently available in literature, provides instances data and results necessary for reproducibility, aiming to become a benchmark for future comparisons with other OICP algorithms

A Fully Polynomial Time Approximation Scheme for the Replenishment Storage Problem

The Replenishment Storage problem (RSP) is to minimize the storage capacity requirement for a deterministic demand, multi-item inventory system where each item has a given reorder size and cycle length. The reorders can only take place at integer time units within the cycle. This problem was shown to be weakly NP-hard for constant joint cycle length (the least common multiple of the lengths of all individual cycles). When all items have the same constant cycle length, there exists a Fully Polynomial Time Approximation Scheme (FPTAS), but no FPTAS has been known for the case when the individual cycles are different. Here we devise the first known FPTAS for the RSP with different individual cycles and constant joint cycle length

The taxation of natural resources : principles and policy issues

Natural resources are typically subject both to taxation under the income tax system and to special resource taxes. Properly designed income taxes attempt to include capital income on a uniform basis. But in most countries the income tax treats resource industries more favorably than most other industries - through favorable treatment of such capital expenses as depletion, exploration and development, and the cost of acquiring resource properties. The case for special resource taxes is precisely to tax resource rents over and above the levies implicit in general income taxes. There are two justifications for this: (a) the efficiency-based argument that a tax on resource rents is nondistorting and complementary; and (b) the equity argument that the property rights to resources ought to accrue to the public at large rather than to private citizens since the rents represent the bounty nature has bestowed on the economy rather than a reward for economic effort. If the main purpose of a resource tax is to capture rents for the public sector, the base of resource taxes should be economic rents (or their present value equivalent), contend the authors. Actual resource taxes differ from rent taxes in significant ways. Unlike a general income tax - which allows the resource industries to understate capital income - resource taxes often overstate rents. This is because they typically do not offer full deductions for all costs, especially capital costs. Some systems tax revenues without allowing any deductions for costs; others allow the deduction of current costs only. As a result, they discourage investment activity in resource industries, encourage the exploitation of high-grade relative to low-grade resources, and make it difficult to impose high tax rates for fear of making the marginal tax rate higher than 100 percent. The authors discuss three alternative ideal ways for the government to divert a share of rents to the public sector: levy a tax on rents, ideally in the form of a cash flow tax; require firms to bid for the rights to exploit resources; and take a share of equity in the firm. They discuss these options in terms of their implications for the ability of firms to obtain finance, the allocation of risk, the share of rents accruing to the public sector, the extent of involvement of foreign firms, and other factors. The time has come in many countries, they say, when gains from further refinement of imperfect existing taxes on resources are less than replacing them with simpler, more efficient forms of pure rent taxes.Environmental Economics&Policies,Public Sector Economics&Finance,Economic Theory&Research,Banks&Banking Reform,Tax Law

Supply Chain Coordination with Quantity Discount for Seasonal Demand

Coordination between manufacturers and multiple buyers represents an important problem in supply chain management. In this paper, we develop a supply chain coordination mechanism in a system with a dominant manufacturer that delivers seasonal products to a group of buyers. These buyers have common replenishment times and receive delivery through a common delivery channel. A twice-stage ordering and production system is introduced in which the first order is placed at some time in advance of the selling season and a second order is placed closer to the selling period. This reorder strategy allows the buyer to collect additional information about seasonal demand, thereby reducing demand forecast error and simultaneously smoothing out production time. This twice-stage model results in savings for both manufacturer and the buyers. Strategies for developing sustainable cooperation between manufacturers and buyers are discussed in light of the conclusions of this model

Audits of agricultural producers and agricultural cooperatives (1987); Audit and accounting guide:

https://egrove.olemiss.edu/aicpa_indev/1223/thumbnail.jp

Audits of agricultural producers and agricultural cooperatives with conforming changes as of May 1, 1994; Audit and accounting guide:

https://egrove.olemiss.edu/aicpa_indev/1226/thumbnail.jp

Business Models for Sustainable Consumption : Identifying and Overcoming Barriers to Rental and Reuse of Home Furnishings

It is widely recognised that society is consuming at levels and in ways that are unsustainable. Sustainable business models, broadly defined as those that consider economic, ecological and social value, hold promise for shifting consumption patterns. By facilitating activities such as rental and reuse, including second-hand, repair, refurbishment, and upcycling, they can help to provide more sustainable options for consumers to acquire, utilise and dispose of products. This, in turn, can extend product lifetimes, keep products from going to waste, and reduce the need for new production. Yet despite the potential of these business models, there are still relatively few of them in the business-to-consumer market.This thesis aims to understand why we do not see more rental and reuse business models in practice, and how these models can become more prevalent. It does so by addressing two research questions: what barriers rental and reuse business models encounter, and how these barriers can be overcome. It focuses on the home furnishings sector, while also bringing in lessons from and for other consumer goods.Through interviews with consumer goods rental companies, document analysis of company marketing materials, and a case study of Sweden’s pioneering reuse-based shopping mall, ReTuna, the thesis finds that rental and reuse business models encounter a number of barriers regarding finance and economics, product design, capabilities, relationships, consumers, and policy. Home furnishings pose particular challenges due to their bulky nature, wide range of products, and uncertainties regarding consumer use patterns. The thesis also finds strategies through which the barriers can be addressed, including reducing or eliminating the barriers directly through the design of the business models, involving other actors, associating new offerings with concepts that are already familiar to consumers, and outweighing or offsetting the barriers by emphasising added benefits. In addition, it suggests that consumer-related barriers regarding desire for ownership and hygiene concerns about not-new goods may not be as substantial as previous research would imply.The findings in this thesis are relevant for researchers interested in understanding how business models that can facilitate sustainable consumption can become more prevalent, as well as for companies and other societal actors seeking or struggling to offer opportunities for rental and reuse of home furnishings and other consumer goods

Audits of agricultural producers and agricultural cooperatives with conforming changes as of May 1, 1993; Audit and accounting guide:

https://egrove.olemiss.edu/aicpa_indev/1225/thumbnail.jp

Audits of agricultural producers and agricultural cooperatives with conforming changes as of May 1, 1992; Audit and accounting guide:

https://egrove.olemiss.edu/aicpa_indev/1224/thumbnail.jp

Audits of agricultural producers and agricultural cooperatives with conforming changes as of May 1, 1996; Audit and accounting guide:

https://egrove.olemiss.edu/aicpa_indev/1227/thumbnail.jp