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The purpose of this paper is twofold. First, it is to introduce a knowledge‐based system for planning processes for families of final products, instead of component items, be they parts or assemblies. Second, it is to demonstrate the feasibility and potential of a prototypical system developed for planning processes families for truck families from a multinational company.

The authors first identify the challenges in planning process families, including data and knowledge representation and constraint handling. To accommodate these challenges, the paper adopts the integrated product and process structure (IP²S) and colored timed Petri nets (CTPNs) in the proposed knowledge‐based process family planning system. On top of the IP²S and CTPNs, XML‐based knowledge representation is employed to alleviate the difficulties in modelling complex product and process family data and planning knowledge while enabling information exchange across different operating platforms. In addition, in accordance with the correspondence between PNs and knowledge‐based systems, a mechanism is designed to cope with the generation of production rules, which model constraints.

The proposed system is able to automatically generate production processes for customized products. At a higher level, such production processes provide input (e.g. operations, machines) to downstream activities for planning process details to manufacture component parts or component assemblies.

Traditional trial and error approaches to planning processes limit production performance improvement when companies need to timely produce diverse customized products. Knowledge‐based systems should be developed to help companies better plan production processes based on the available manufacturing resources.

Unlike most reported studies addressing either detailed process planning or assembly planning for component parts or component assemblies, this study tackles process planning for final products, in attempting to maintain production efficiency from a holistic view.

Scheduling of production in a wire rope factory is complicated by several features: (a) the simultaneous requirement for two types of limited resource, machines and bobbins; (b) multi‐stage production with normally two or three stranding and one or two closing operations; (c) queuing at the closing machines; the typical job splits into sub‐batches when passing from the stranding to the closing operation; these sub‐batches usually queue at the closing operations which, being faster than stranding operations, generally receive work from several queues; (d) alternative choices in the selection of machines and bobbin sizes for any given stranding or closing operation; (e) the presence of random elements in the timing of machine breakdowns and repairs. In this case study factory in a developing country, the existing control of production flows was ad hoc rather than according to a specified method. The management needed to know whether a scientific scheduling approach could significantly improve the low utilisation of machines. As a first attempt a strategy was synthesised based on well‐known concepts from the theory of scheduling in static and dynamic environments, taking into consideration certain effects of the complicating factors mentioned above. Simulation revealed that a significant improvement was possible.

The purpose of this paper is to advance new rules about operations of grey numbers based on kernels and greyness and analyze the reliability of these new operations.

A grey number is usually represented as a closed interval or a discrete set of numbers. Based on the definition of traditional grey number, novel rules that grey numbers can be represented as their kernels and associated degrees of greyness are proposed. In new rules, the operation between kernels of grey numbers has significance in the application of grey numbers. The reliability of operations of grey numbers using their kernels and the degrees of greyness derived from kernel operations and their corresponding interval operations are studied.

The results show that the novel rules about operation of grey numbers satisfy to the concept of grey system properly. It is useful to calculate the grey degree of grey numbers and the process of calculating is easier than traditional operation rules.

The method exposed in the paper can be used to calculate each two grey numbers. The grey degree and the calculating results of two grey numbers can be given out easily. The method can also be used to calculate grey numbers more than two.

The paper succeeds in constructing novel operation rules of grey numbers. The reliability of novel operation rules is studied and it is new development of grey systems theory, undoubtedly.

This paper proposes a systematic scheme for synthesizing formal specification from the definitions of relational data model – entity relationship diagram and their data dictionaries. The formal specification of both structural and behavioral properties of relational data model is generated in Z schemas. In our approach, the mandatory structural constraints – the uniqueness of primary key, foreign keys, and referential integrity constraints among the relations in the model, are preserved. We propose a set of transformation rules to produce Z schemas of the states and primitive operations – cascade insertion, deletion, and updating. Moreover, a composition technique of constructing the composite operations is presented by using requirements particle networks. The revision of the formal specification can be easily conducted with the mathematical proofs of the properties of the data model using Z prover tool.

The purpose of this paper is to advance new rules about operations of grey sets based on grey numbers and greyness and investigate their capability in reducing uncertainty.

A grey set can have its characteristic function values restricted by grey numbers, and such a representation makes the operations of grey sets different from other sets. Based on the concept of whitenisation of grey sets, two extended operations of grey sets are defined and their properties are discussed.

The result demonstrates that the proposed meet operation can significantly reduce uncertainty in grey sets and that the novel rules about operation of grey sets can reduce uncertainty of the set significantly. The propagation of uncertainty under different operations is investigated.

The method exposed in the paper can be used to integrate information from different sources to reduce uncertainty in information.

The paper succeeds in constructing novel operation rules of grey sets. The capability of novel operation rules to reduce uncertainty is studied and it is a new development of grey systems theory.

The purpose of this paper is to advance new rules about operations of grey numbers.

The paper first puts forward the definitions of basic element of grey number and general grey number. The operation axiom, operation rules of general grey numbers and a new algebraic system for general grey numbers are built based on the “kernel” and the degree of greyness of grey numbers.

Up to now, the operation of general grey numbers has been transformed to operation of real numbers; thus, the difficult problem for set up operation of general grey numbers has been solved to a certain degree.

The method exposed in the paper can be used to integrate information from a different source. The operation of general grey numbers could be extended to the case of grey algebraic equation, grey differential equation and grey matrix which includes general grey numbers. The operation system of general grey numbers also opened a new passageway for research on grey input‐output and grey programming, etc.

The new conception of a basic element of grey number and general grey number was given for the first time in this paper. The novel operation rules of general grey numbers were also constructed.

The purpose of this paper is to provide a brief history on the Part 15 rules.

The approach takes the form of a systematic overview of spectrum policy applied to rules governing unlicensed devices since 1938.

Much of the policy debate in the last decade has been couched in terms of how spectrum rights are defined. The jurisprudence underlying the Part 15 rules is that unlicensed spectrum is not spectrum at all. Rather, the rules concentrate on the effective power and modulation characteristic of the radio devices themselves. Perhaps this is the next great idea for all spectrum policy: spectrum does not really exist. It is merely an idea – a concept – a way of describing and organizing the physical world in people's minds and actions. Spectrum is a legal and engineering construct to control for an immutable fundamental physical property.

Research limitations encompass typical limitations of a case study of a historical event.

The paper informs ongoing efforts to update and modernize spectrum policy.

The paper provides a retrospective view of spectrum policy.

This paper aims to summarize amendments to Rule 22c‐2 under the Investment Company Act of 1940, the “redemption fee rule”, adopted by the Securities and Exchange Commission on September 26, 2006.

Provides background to the redemption fee rule, defines financial intermediaries and intermediary chains, and discusses how funds are expected to implement the rule and associated frequent trading policies.

Under the redemption fee rule, the boards of most mutual funds are required to consider whether to implement a fee of up to 2 percent of the value of any shares redeemed by a customer from a fund within a short time after purchase. Amendments to the rule clarify operation of the rule and reduce mutual funds' costs in complying with it.

Outlines the requirements of the amendments to Rule 22c‐2 under the Investment Company Act of 1940.

Scheduling is defined by Baker as, “the allocation of resources over time to perform a collection of tasks”. The term facilities is often used instead of resources and the tasks to be performed may involve a variety of different operations.

A theory of local rules was developed using Kauffman and Holland’s work on fitness landscapes. Local rules are used by individuals to increase their chances of survival on a fitness landscape. This paper reports on results from a simulation model of the local rules used by managers in the operation of a kanban system. In this case, local rules were used to optimise chances of survival by deflecting senior management criticism of potential stockouts in the system. The local rules used by the managers were modelled and their success and unintended consequences were reported. Some tentative conclusions about the effectiveness of local rules were advanced.