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Multiple impact characterization of wafer level packaging (WLP)Original Research ArticleMicroelectronics ReliabilityProcessing and properties of engineering plastics recycled from waste electrical and electronic equipment (WEEE)Original Research ArticlePolymer Degradation and StabilityAnalytical models for shock isolation of typical components in portable electronicsOriginal Research ArticleInternational Journal of Impact EngineeringTheoretical models can help to guide the cushion design for portable electronics. In the theory of shock isolation, mass-spring model has been mostly adopted to describe the shock response of a system. However, since the mass-spring model ignores the deflection of the fragile equipment and the coupling of the equipment with its supports, it may not be adequate to apply to flexible electronic components such as printed circuit board. In the present paper, a comprehensive study is carried out for both mass-spring systems and flexible beam structures. Particular attention is paid to the maximum force sustained by the connecter, the maximum relative displacement and the vibration amplitude with respect to shock duration. It is found that as long as the shock duration exceeds 0.3 times of the basic period, the beam structure can still be simplified as mass-spring model. However, about 10 vibration modes should be considered in order to achieve a good estimation, if the shock duration is much shorter than the natural period. Results show that better cushion effect can be achieved when the shock duration exceeds 2.5 times of the natural period of the response system. A notable phenomenon found in this research is that the maximum strain is independent of the dimension of the beam.Article Outline1. Introduction2. Mass-spring model 2.1. Model description2.2. The effect of drop velocity and peak acceleration2.3. The effect of isolation spring2.4. The effect of pulse duration for fixed impact velocity3. Beam model 3.1. Simply supported beam3.2. Clamped beam4. Conclusions9 articles found for: pub-date 2004 and tak(More than 900 mhz) or (antenna design) or Experience or (Practical experience) or (mass production) or UHF or (microwave antenna design) or (simulation and debugging) or (The physical realization) or (antenna products) or (Product applications) or (the chip antenna structure) or design or verification or implementation) and (ADS or hss or (other electromagnetic simulation tools) or ( protel SE) or DXP or (Power PCB) or ( graphics software) or (able to skillfully use) or (a variety of microwave) or (test equipment) Electronic components and packagingMeasurements and predictions of the air distribution systems in high compute density (Internet) data centersOriginal Research ArticleEnergy and BuildingsWhen equipment power density increases, a critical goal of a data center cooling system is to separate the equipment exhaust air from the equipment intake air in order to prevent the IT server from overheating. Cooling systems for data centers are primarily differentiated according to the way they distribute air. The six combinations of flooded and locally ducted air distribution make up the vast majority of all installations, except fully ducted air distribution methods. Once the air distribution system (ADS) is selected, there are other elements that must be integrated into the system design. In this research, the design parameters and IT environmental aspects of the cooling system were studied with a high heat density data center. CFD simulation analysis was carried out in order to compare the heat removal efficiencies of various air distribution systems. The IT environment of an actual operating data center is measured to validate a model for predicting the effect of different air distribution systems. A method for planning and design of the appropriate air distribution system is described. IT professionals versed in precision air distribution mechanisms, components, and configurations can work more effectively with mechanical engineers to ensure the specification and design of optimized cooling solutions.Article OutlineNomenclature1. Introduction and methods2. Overview of data center cooling 2.1. Environmental requirements2.2. Hot-aisle and cold-aisle arrangements2.3. Types of air distribution systems (ADS)3. Thermal evaluation of a data center 3.1. Summary of measurements3.2. Thermal imaging and temperature measurements of an IT sever room4. The computational model 4.1. The base configurations4.2. Heat flux equations4.3. Numerical method4.4. CFD model construction5. Numerical results and discussions 5.1. Heat removal performance of ADS 5.1.1. Air temperature distribution5.1.2. Air velocity distribution5.2. Implemented hot-aisle/cold-aisle arrangement5.3. Summary of results6. Conclusions and future workReferencesA comprehensive simulation model for immunity prediction in integrated circuits with respect to substrate injectionOriginal Research ArticleMicroelectronics JournalThis paper presents a comprehensive modelling methodology for the electromagnetic immunity of integrated circuits (ICs) to direct power injection (DPI). The aim of this study is to predict the susceptibility of ICs by the means of simulations performed on an appropriate electrical model of different integrated logic cores located in the same die. These cores are identical from a functional point of view, but differ by their design strategies. The simulation model includes the whole measurement setup as well as the integrated circuit under test, its environment (PCB, power supply) and the substrate model of each logic core. Simulation results and comparisons with measurement results demonstrate the validity of the suggested model. Moreover, they highlight the interest of the aforementioned protection strategies against electromagnetic disturbances.Article Outline1. Introduction2. Description of the test chip3. Direct power injection (DPI) method: set-up and modelling 3.1. Set-up of the injection system3.2. Modelling of the injection system and the PCB3.3. Modelling of the integrated circuit package and bonding3.4. Modelling of CESAME cores 3.4.1. Substrate modelling for the NORM core3.4.2. Substrate modelling for the ISO core3.4.3. Substrate modelling for the RC core4. Results5. Discussion and comparison among results 5.1. Measurement results5.2. Simulation results6. ConclusionReferencesActive cooling of a mobile phone handsetOriginal Research ArticleApplied Thermal EngineeringPower dissipation levels in mobile phones continue to increase due to gaming, higher power applications, and increased functionality associated with the internet. The current cooling methodologies of natural convection and radiation limit the power dissipation within a mobile phone to between 1-2W depending on size. As power dissipation levels increase, products such as mobile phones will require active cooling to ensure that the devices operate within an acceptable temperature envelop from both user comfort and reliability perspectives. In this paper, we focus on the applied thermal engineering problem of an active cooling solution within a typical mobile phone architecture by implementing a custom centrifugal fan within the mobile phone. Its performance is compared in terms of flow rates and pressure drops, allowable phone heat dissipation and maximum phone surface temperature as this is the user constraint for a variety of simulated PCB architectures in the mobile phone. Perforated plates with varying porosity through different size orifices are used to simulate these architectures. The results show that the power level dissipated by a phone for a constant surface temperature may be increased by 50-75% depending on pressure drop induced by the internal phone architecture. Hence for successful implementation and efficient utilization of active cooling will require chip layout to be considered at the design stage.Article OutlineNomenclature1. Introduction2. Experimental 2.1. Influence of case temperature on quantification of allowable heat dissipation3. Results and discussion4. ConclusionsAcknowledgementsReferencesCombination Approach of FEM and Circuit System in IR Drop Ana