A case based model to assist in the design process in the manufacture of furniture products

This paper describes progress on a project to utilise case based reasoning methods in the design and manufacture of furniture products. The novel feature of this research is that cases are represented as structures in a relational database of products, components and materials. The paper proposes a method for extending the usual "weighted sum" over attribute similarities for a ·single table to encompass relational structures over several tables. The capabilities of the system are discussed, particularly with respect to differing user objectives, such as cost estimation, CAD, cutting scheme re-use, and initial design. It is shown that specification of a target case as a relational structure combined with suitable weights can fulfil several user functions. However, it is also shown that some user functions cannot satisfactorily be specified via a single target case. For these functions it is proposed to allow the specification of a set of target cases. A derived similarity measure between individuals and sets of cases is proposed.

Cohabitation: quantifying an equitable share

Discusses the House of Lords judgment in Stack v Dowden on the factors the courts may consider when determining whether to rebut the presumption that former cohabitees, who were registered as joint legal owners of a property, were also joint beneficial owners with equal shares in the property. [From the Legal Journals Index]

Scheduling for parallel dedicated machines with a single server

This paper examines scheduling problems in which the setup phase of each operation needs to be attended by a single server, common for all jobs and different from the processing machines. The objective in each situation is to minimize the makespan. For the processing system consisting of two parallel dedicated machines we prove that the problem of finding an optimal schedule is NP-hard in the strong sense even if all setup times are equal or if all processing times are equal. For the case of m parallel dedicated machines, a simple greedy algorithm is shown to create a schedule with the makespan that is at most twice the optimum value. For the two machine case, an improved heuristic guarantees a tight worst-case ratio of 3/2. We also describe several polynomially solvable cases of the later problem. The two-machine flow shop and the open shop problems with a single server are also shown to be NP-hard in the strong sense. However, we reduce the two-machine flow shop no-wait problem with a single server to the Gilmore-Gomory traveling salesman problem and solve it in polynomial time. (c) 2000 John Wiley & Sons, Inc.

Two-machine open shop scheduling with special transportation times

The paper considers a problem of scheduling n jobs in a two-machine open shop to minimise the makespan, provided that preemption is not allowed and the interstage transportation times are involved. In general, this problem is known to be NP-hard. We present a linear time algorithm that finds an optimal schedule if no transportation time exceeds the smallest of the processing times. We also describe an algorithm that creates a heuristic solution to the problem with job-independent transportation times. Our algorithm provides a worst-case performance ratio of 8/5 if the transportation time of a job depends on the assigned processing route. The ratio reduces to 3/2 if all transportation times are equal.

Proportionate flow shop with controllable processing times

This paper considers a special class of flow-shop problems, known as the proportionate flow shop. In such a shop, each job flows through the machines in the same order and has equal processing times on the machines. The processing times of different jobs may be different. It is assumed that all operations of a job may be compressed by the same amount which will incur an additional cost. The objective is to minimize the makespan of the schedule together with a compression cost function which is non-decreasing with respect to the amount of compression. For a bicriterion problem of minimizing the makespan and a linear cost function, an O(n log n) algorithm is developed to construct the Pareto optimal set. For a single criterion problem, an O(n2) algorithm is developed to minimize the sum of the makespan and compression cost. Copyright © 1999 John Wiley & Sons, Ltd.

A fully polynomial approximation scheme for the single machine weighted total tardiness problem with a common due date

We develop a fully polynomial-time approximation scheme (FPTAS) for minimizing the weighted total tardiness on a single machine, provided that all due dates are equal. The FPTAS is obtained by converting an especially designed pseudopolynomial dynamic programming algorithm.

Financing of SME's: an asset side story

The main sources of financing for small and medium sized enterprises (SMEs) are equity (internally generated cash), trade credit paid on time, long and short term bank credits, delayed payment on trade credit and other debt. The marginal costs of each financing instrument are driven by asymmetric information (cost of gathering and analysing information) and transactions costs associated with non-payment (costs of collecting and selling collateral). According to the Pecking Order Theory, firms will choose the cheapest source in terms of cost. In the case of the static trade-off theory, firms choose finance so that the marginal costs across financing sources are all equal, thus an additional Euro of financing is obtained from all the sources whereas under the Pecking Order Theory the source is determined by how far down the Pecking Order the firm is presently located. In this paper, we argue that both of these theories miss the point that the marginal costs are dependent of the use of the funds, and the asset side of the balance sheet primarily determines the financing source for an additional Euro. An empirical analysis on a unique dataset of Portuguese SME's confirms that the composition of the asset side of the balance sheet has an impact of the type of financing used and the Pecking Order Theory and the traditional Static Trade-off theory are rejected.

Private equity and employment - the Davos/WEF/Harvard study

The World Economic Forum at Davos has published a major study showing that workplaces of firms taken over by private equity have 10% less employees 5 years after the takeover, than other similar workplaces. The rate of plant closures, opening, acquisitions and disposals is twice as high as in other firms, and the net effect is still a job loss of 3.6%-4.5% after only 2 years, compared with other firms. Firms taken over by private equity are also more likely to go bankrupt than publicly quoted firms.