Sharif Digital Repository

This paper presents a sequence of affordable methods applied to diagnose a millimeter-wave system-in-package. The module used in this paper is a 60 GHz transceiver with a waveguide interface, designed to transmit 8 dBm of saturated power. It consists of a flip-chipped RFIC, a multi-layer organic substrate, a metal enclosure with a standard waveguide interface, passive components and a 30-pin connector. The first measured output power was 3 to 6 dB below the desired value over the 60 GHz band. Thus, all parts of the module were thoroughly investigated to detect the cause of power drop. By 3-D electromagnetic simulation of the enclosure, the cavity modes and power leakage in the enclosure were... 

Economic production and on-time ordering are among the most important topics related to production and inventory control issues. An economical production needs a comprehensive and precise planning to be implemented in all production stages. To have a controlled and comprehensive planning system, economic order quantity (EOQ) or economic production quantity (EPQ) models are usually used in various production-inventory environments to minimize costs, avoid delays in orders, and achieve high performance. To meet the demands, sometimes a multiperiod production-inventory planning that involves several products requires outsourcing. In this paper, a production-procurement plan that integrates EOQ... 

Interactive and integrated design and manufacturing can be a useful strategy for designers to reach the efficient design through the cognitive or physical interactions. Process tolerance design is a key tool in the integrated design and manufacturing to reach a product with high quality and low cost. Since the optimal tolerance allocation involves several aspects of the design, manufacturing and quality issues, it is always a time consuming and difficult procedure, especially for complex products. Therefore, to overcome these difficulties, a computer-aided approach for optimal tolerance design of manufacturing process is needed in the design stage. In this paper, a novel interactive... 

Imprecise productions with low quality are produced by the incapable manufacturing processes. Prediction of the process capability in the design stage plays a key role to improve the product quality. In this paper, a new method is proposed to optimally reduce the locating error by allocating the minimum adjustments of locators. To quantify the precision of the manufacturing process, a proper tool that is called the geometric capability ratio (GCR) of the manufacturing process is introduced. First, based on a part fixture model, the relationship between the locating error and its sources is developed. Then, using the proposed geometric capability ratio, the manufacturing process capability is... 

In this paper a web based production system is proposed. This system consists of a web services agent to manage the receipt the order from the customer, a price agent to predict the price of the product for the customer, a decision agent to build up a virtual enterprise to manufacture and deliver of the product to the customer and make essential decisions of the system and a design and control agent to do the engineering tasks related to the production process of the product. This structure provides the production system with a high level of agility and flexibility. © 2019 IEEE  

Interactive and integrated design and manufacturing can be a useful strategy for designers to reach the efficient design through the cognitive or physical interactions. Process tolerance design is a key tool in the integrated design and manufacturing to reach a product with high quality and low cost. Since the optimal tolerance allocation involves several aspects of the design, manufacturing and quality issues, it is always a time consuming and difficult procedure, especially for complex products. Therefore, to overcome these difficulties, a computer-aided approach for optimal tolerance design of manufacturing process is needed in the design stage. In this paper, a novel interactive... 

Intense global competition, dynamic product variations, and rapid technological developments force manufacturing systems to adapt and respond quickly to various changes in the market. Such responsiveness could be achieved through new paradigms such as Reconfigurable manufacturing systems (RMS). In this paper, the problem of configuration design for a scalable reconfigurable RMS that produces different products of a part family is addressed. In order to handle demand fluctuations of products throughout their lifecycles with minimum cost, RMS configurations must change as well. Two different approaches are developed for addressing the system configuration design in different periods. Both... 

Intense global competition, dynamic product variations, and rapid technological developments force manufacturing systems to adapt and respond quickly to various changes in the market. Such responsiveness could be achieved through new paradigms such as Reconfigurable manufacturing systems (RMS). In this paper, the problem of configuration design for a scalable reconfigurable RMS that produces different products of a part family is addressed. In order to handle demand fluctuations of products throughout their lifecycles with minimum cost, RMS configurations must change as well. Two different approaches are developed for addressing the system configuration design in different periods. Both... 

Intense global competition, dynamic product variations, and rapid technological developments force manufacturing systems to adapt and respond quickly to various changes in the market. Such responsiveness could be achieved through new paradigms such as Reconfigurable manufacturing systems (RMS). In this paper, the problem of configuration design for a scalable reconfigurable RMS that produces different products of a part family is addressed. In order to handle demand fluctuations of products throughout their lifecycles with minimum cost, RMS configurations must change as well. Two different approaches are developed for addressing the system configuration design in different periods. Both... 

This article investigates the basis for pressure sensor application based on the magnetic shape memory effect in membranes. Von Karmans nonlinear terms are considered in strain–displacement relationships of thin films, and a new method is presented for solution of large deflections of thin films with arbitrary boundary condition. In this study, the equations of motion of magnetic shape memory alloys are extended. In pressurized membranes, the complex distribution of mechanical stress can cause the martensitic reorientation, which is the underlying mechanism for sensing applications in magnetic shape memory alloys. To examine the obtained model, the governing equations of magnetic shape... 

Maximizing the value of resources and producing less waste are strategic decisions affecting sustainability and competitive advantage. Sustainable closed-loop supply chains (CLSCs) are designed to minimize waste by circling back (repairing, reselling, or dismantling for parts) previously discarded products into the value chain. This study presents a novel two-stage fuzzy supplier selection and order allocation model in a CLSC. In Stage 1, we use the fuzzy best-worst method (BWM) to select the most suitable suppliers according to economic, environmental, social, and circular criteria. In Stage 2, we use a multi-objective mixed-integer linear programming (MOMILP) model to design a... 

Gamma irradiation systems are used extensively in the industry in order to sterilize medical devices, disinfect hygienic products and increase the shelf life of agricultural products. The method of gamma irradiation is superior to the older methods of heat or chemical treatment because it is by far a simpler operation. In this method, only one parameter, the exposure time is controlled, whereas in the other mentioned methods five or six different parameters need to be controlled. The design of irradiation systems generally includes the size and the location of products, and the arrangement of source rack pencils. In order to optimize the design of the gamma irradiation systems, it is needed... 

Real-time measurement of soil water pressure has been recognized as an essential part of investigating water ow in unsaturated soils. Tensiometry, amongst di erent measuring techniques, is a common method for direct evaluation of water pressure. However, the lower limit of measurable water pressure by a conventional tensiometer becomes even more limited by increasing its length in the vertical installation. This paper describes the development of a Vacuum-Re lled Tensiometer (VRT) for monitoring soil water pressure independent of installation depth. This is achieved by xing the distance between pressure sensor and ceramic cup together with incorporating an ancillary vacuum-re lling assembly... 

One of the most important goals of any organization for a product that goes into the design or manufacturing process is to improve its reliability. Reliability growth is defined as improving a product's criteria (input parameters) during operation using changes in design or production. This paper presents a hardware-centric approach for the reliability growth of systems following normal distribution based on the Non-Homogeneous Poisson Process (NHPP). To reach this goal, the reliability growth modeling equations for the NHPP with the assumption of the normal distribution for failure data are extracted and obtained. Then, the maximum likelihood estimation technique based on the... 

Electrostatically actuated beams are fundamental blocks of many different nano and micro electromechanical devices. Accurate design of these devices strongly relies on recognition of static and dynamic behavior and response of mechanical components. Taking into account the effect of internal forces between material particles nonlocal theories become highly important. In this paper nonlinear vibration of a microano doubly clamped and cantilever beam under electric force is investigated using nonlocal continuum mechanics theory. Implementing differential form of nonlocal constitutive equation the nonlinear partial differential equation of motion is reformulated. The equation of motion is... 

The Failure Modes and Effects Analysis (FMEA) method has been used to study the reliability of many different power generation systems. This paper now applies that method to a wind turbine (WT) system using a proprietary software reliability analysis tool. Comparison is made between the quantitative results of an FMEA and reliability field data from real wind turbine systems and their assemblies. These results are discussed to establish relationships which are useful for future wind turbine designs. The main system studied is an existing design 2 MW wind turbine with a Doubly Fed Induction Generator (DFIG), which is then compared with a hypothetical wind turbine system using the Brushless...