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The purpose of this study is, to compare laser-based additive manufacturing and subtractive methods. Laser-based manufacturing is a widely used, noncontact, advanced manufacturing technique, which can be applied to a very wide range of materials, with particular emphasis on metals. In this paper, the governing principles of both laser-based subtractive of metals (LB-SM) and laser-based powder bed fusion (LB-PBF) of metallic materials are discussed and evaluated in terms of performance and capabilities. Using the principles of both laser-based methods, some new potential hybrid additive manufacturing options are discussed.

Production characteristics, such as surface quality, dimensional accuracy, material range, mechanical properties and applications, are reviewed and discussed. The process parameters for both LB-PBF and LB-SM were identified, and different factors that caused defects in both processes are explored. Advantages, disadvantages and limitations are explained and analyzed to shed light on the process selection for both additive and subtractive processes.

The performance of subtractive and additive processes is highly related to the material properties, such as diffusivity, reflectivity, thermal conductivity as well as laser parameters. LB-PBF has more influential factors affecting the quality of produced parts and is a more complex process. Both LB-SM and LB-PBF are flexible manufacturing methods that can be applied to a wide range of materials; however, they both suffer from low energy efficiency and production rate. These may be useful when producing highly innovative parts detailed, hollow products, such as medical implants.

This paper reviews the literature for both LB-PBF and LB-SM; nevertheless, the main contributions of this paper are twofold. To the best of the authors’ knowledge, this paper is one of the first to discuss the effect of the production process (both additive and subtractive) on the quality of the produced components. Also, some options for the hybrid capability of both LB-PBF and LB-SM are suggested to produce complex components with the desired macro- and microscale features.

The purpose of this paper is to apply the developed systematic mechanical design methodologies, that are obtained in part I, to investigate their success in designing mechanics of a flexible printed circuit board assembly (PCBA) rework cell.

The decision of soldering and desoldering tool, which is the most critical function of a PCBA rework or remanufacturing cell, significantly influences overall design concept. Therefore, the paper starts by applying the design methodology to the soldering and desoldering function. The same study is repeated for the rest of the sub‐functions but only the results are provided.

An application of rework machine design methodology for the design of a PCBA rework cell has been made available. In addition to this, the embedded knowledge, such as the requirements list, the function structure, the function/means tree, the weighted objective tree and evaluation chart for the soldering and desoldering function are provided.

The paper is the first work providing both embedded knowledge and the application of the systematic design methodology for the design of a fully automated flexible PCBA rework cell. The methodology leads rework machine designers in a well‐controlled and structured design environment.

The design methodology can be applied to all functions or targeted on key weighted areas to ensure that the designed rework machine meets the key areas of concerns. Furthermore, the methodology is generic and may be used to develop other complex manufacturing sytems.

Eighty‐five participants attended the 4th ISHM Display meeting at the Jaarbeurs Congress Centre in Utrecht on 16 October, 1986. The programme of the day started with the annual general membership meeting of the Benelux Chapter. The chairman, Mr T. Kwikkers, gave a short review of the state of affairs of ISHM‐Benelux and of the activities of the last year. He mentioned the temporary enlargement of the executive committee to give a new generation a chance to gain experience in the ISHM organisation and to take up some new activities. In order to raise publicity for ISHM and Hybrid Circuits a new brochure has been designed and a set of material for demonstration purposes was collected. With the material every member of the chapter can easily set up a presentation for schools or customers. This year ISHM‐Benelux has grown from 85 to 100 members and enjoys a healthy financial situation. Next year again emphasis will be put on public relations. Professor R. Govaerts signified that he was no longer available for a position in the executive committee. As Prof. Govaerts has been very active and stimulating for the ISHM‐Benelux Chapter from its foundation in 1976 up to now, the general membership meeting decided to appoint him as (the first) honorary member of this chapter. Except for Professor Govaerts, the sitting executive committee, consisting of 15 members, was re‐elected for another year. After the European conferences in Bournemouth and Hamburg the ISHM‐Benelux chapter is asked to organise the 1991 Conference. The executive committee is already looking out for candidates for a function in the organising committee, which must be formed in the coming year.

The purpose of this paper is to discuss medium‐power amplifier (MPA) design using parasitic‐aware core‐based approach.

This paper discusses a core‐based design approach, which can also deliver multi‐band radio frequency integrated circuit.

A fabricated 3.5 GHz MPA achieved a P1dB of 16.81 dBm, power‐added efficiency (PAE) of 16.74 percent and gain of 6.81 dB at the 10 dBm of input power under a low‐power supply of 3 V. The maximum current, I_max is 80.7 mA and the power consumption of the device is 242.10 mW. A fabricated 2.4 GHz MPA achieved a P1dB of 14.83 dBm, PAE of 11.73 percent and gain of 9.83 dB at the 5.0 dBm of input power under a low‐power supply of 3.0 V. The maximum current, I_max is 84.4 mA and the power consumption for this device is 253.20 mW.

This paper shows the merits of the parasitic‐aware design methods used in designing the core circuit.

The purpose of this paper is to investigate the temperature reliability for a parallel high-efficiency class-E power amplifier (PA).

To explore the relationship between temperature and direct current (DC) characteristics, output power, S parameters and efficiency of the PA quantitatively, a series of reliability experiments have been designed and conducted to study the temperature reliability for this PA.

From the results, the prominent performance degradation even failure is found during the testing. Furthermore, the thermal shock test can cause permanent failure, which is a great threat for PA.

Therefore, to ensure the good performance, the influence of temperature on PA reliability should be carefully considered during the stage of PA design.

All these can provide important guidance for the reliability design of PA.

All these can give some important guidance for PA application.

In addition, PA is usually designed according to the electrical properties at the room temperature. From the results above, it can be concluded that it may be unable to satisfy the performance requirement at high temperature. In turn, if it is designed according to the electrical properties at low temperature, the transistor often works in the super-saturated state, the reliability of PA will become the new problem. Therefore, to ensure the good performance, the influence of temperature on PA reliability should be carefully considered during the design.