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The purpose of this paper is to propose a miniaturized tri-band bandstop filter that finds application in a modern dense communication system where size and multi-band plays a vital role.

In this paper, the authors propose a miniaturized tri-band microstrip bandstop filter which combines the conventional bandstop filter and spur microstrip line structures such that this design achieves tri-band operation at 1.8 GHz and 3 GHz. The overall length of the microstrip filter is found to reduce from 126 to 45 mm because of introduction of spur lines and via-hole grounding. The addition of spur lines replaces two resonators, introduces two additional resonant frequencies and enhances the −6 dB bandwidth of the center frequency by 14 %.The addition of via-holes in each resonator reduces its length into half of its original length, thereby reducing filter size.

Resonance occurs at three different frequencies 1.8, 2.4 and 3 GHz. The filter size reduces from 126 to 45 mm, and the −6 dB rejection bandwidth of center frequency improves by 14 %.

The overall filter size is reduced by 65% and it resonates at three different frequencies 1.8, 2.4 and 3 GHz with an improved bandwidth of 10 % around the center frequency.

In features based design systems that are underpinned by solid models, buildings are designed by applying features to the design domain. A feature may be translated and/or rotated in order to position it in the desired place. Contradiction between the applied features and resulting features may occur due to the features interaction, wrong positioning, or inadequate parameters supplied by the user during the product definition. Moreover, the application of other features may cause some features to degenerate to further features. Therefore, verification of the resulting features must be performed against the applied features to establish whether the resulting features conform to the underlying geometry. Current feature‐based design systems employ a mechanism of tagging feature labels onto geometry. This approach does not guarantee the geometric correctness of the resultant feature and knowledge of the topology of the resulting feature and a geometric analysis is necessary to correctly identify the validity of the resultant feature. The research reported in this paper proposes an alternative approach which uses a product model that permits all geometrical and technological information associated with the design and construction stages to be represented. Individual features can be extracted from the product model and analysed to determine their accessibility. Methods which use the product description and other construction data to determine feature validity, accessibility and machinability are used. Each volumetric feature corresponds to a solid that can be added by one or more construction process or removed by one or more machining operations; as a consequence of applying volumetric features, surface features are generated. These surface features provide enough information to enable the accessibility, and machinability of the individual features to be determined and establish the possible routes in which the feature can be accessed if any.

The industrial robot has now become accepted in almost every sector of manufacturing industry as this review of robot applications and specifications shows.

Translated Abstracts of a Selection from the New Post‐war Series of Patents Granted in the German Federal Republic. The invention consists in the provision of the detonator fuse inside the fuselage connected with the explosive cap. The edge of the section of the fuselage (1) is stiffened by a rib (2) to which the strengthening frame (3) for the hood (4) is secured by rivets. Between the strengthening frame (3) and the fastening edge (5) for the hood (4) there is provided a closed detonator fuse (6) which is in connexion with an explosive cap (7) secured to the frame (2). The fuse (6) runs round the hood body (4) on the strengthening frame (3) in the fastening edge (5) above the securing rivets (4) for the hood (4). The explosive cap (7) is protected towards the inside of the fuselage (1) by a protecting wall (8) of armour plating. To the protecting wall (8) there is secured a housing (9) covered by a lid (10) which serves for the reception of the draw ring (11) for firing the explosive cap (7).

The industrial robot when associated with a workpiece magazine or conveyor system loading and unloading one or more numerical controlled machine tools opens a new way for automation in low series production. The possibilities for automatic handling together with machine tools within direct numerical controlled systems are discussed. After dealing with the master control selection and the signal flow some limitations resulting from the robot's kinematics are pointed out. Afterwards an actual manufacturing system, installed at the Berlin University, is introduced.

This paper seeks to analyze the evolution of shift in the area of operations management (OM) and attempts to anticipate potential developments in the relevant areas of OM.

A hybrid approach is adopted to understand how the field of OM has evolved over time relying on the perspectives of both academics and business practitioners. This evolution of shift in the area of OM is examined based on a thorough literature review and the authors’ industrial experience.

From the days of functional point solutions relying on concepts like reorder point to finite capacity planning, OM research at present deals with a set of important problems facing both private and public sectors at the organizational level. Most prominent of these include e‐business, supply chain management, production planning and scheduling, product development, decision support systems, information‐based strategy, systems development and implementation, risk and environmental management. OM has also embraced several organization‐wide philosophies including lean production, mass customization and agile manufacturing.

With the advent of Internet and burgeoning of the new economy, this paper provides important insights regarding the evolution of OM in the past, recent developments at present and what the future holds for this field. It is envisaged that a focus on the issues central to OM will soon propel both researchers and industry practitioners beyond existing technologies and also provide the catalyst for developing new ones.

This paper provides useful insights to both researchers and practitioners who are interested in the field of OM.

The product‐costing techniques developed for conventional job shops are unsuitable for use in computer‐integrated manufacturing systems (CIMS) and their continued use in the CIMS environment generates incorrect and misleading manufacturing costs. A new cost model particularly suited for CIMS that also satisfies all financial accounting requirements is described. The model has two components of manufacturing cost, direct material cost and transformation cost, instead of three in the conventional method, and uses actual machine usage to calculate manufacturing costs. To effect accurate allocation of the transformation cost, first to each machine and then to the product that uses the machine, intermediate pooling of costs and different allocation bases are used. A numerical example is presented to clarify the steps in the procedure.

Effective management of suppliers is one of the ways manufacturing companies can improve their performance. Typically, it has been argued in the literature that close relationships with suppliers should be developed, in contrast to the traditional price‐driven transactional relationships. However, there has been relatively little empirical research on how supplier management is applied.

This paper presents research probing how manufacturers manage their suppliers and takes a sample from Germany – which has a large manufacturing sector. In‐depth interviews with purchasing managers were used to understand whether relationships with suppliers were being utilised.

The analysis of the data indicates that a significant portion of the companies surveyed had experienced a change in their relationship with suppliers in the last few years. In the main, relationships had become closer and the use of partnerships was in evidence.

The research results have implications for German manufacturing companies, as they indicate the potential for improving performance through the greater adoption of best practices in the area of supplier management. The research results indicate the need for German manufacturers to adopt leading‐edge practices in the area of supplier management.

Although exploratory in nature, the investigation demonstrated the need for researchers to better understand the range of relationships in a typical manufacturer's supplier base.

FOR SOME YEARS there has been a tendency for the number of industrial workers to decline and that of clerical staffs to increase.

IT is difficult to imagine the world of Work Study without the urbane ubiquity of Russell Currie, whose death on 28 August we deeply regret to record. Although he had been officially in retirement for a year or two his presence was immanent in any important gathering of those who had so long looked to him for the leadership that was always forthcoming. We can fittingly borrow an epigram he coined at the London Congress in 1963 as apt at this time. ‘The sun shone to greet your arrival; the skies weep for your departure.’