Discrete Packages Research Articles

An 8-Gb 12-Gb/s/pin GDDR5X DRAM for Cost-Effective High-Performance Applications

The graphic DRAM interface standard GDDR5X is developed as an evolutionary extension to the widely available GDDR5. The implementation presented here achieves a data rate of 12 Gb/s/pin on a single-ended signaling interface with 32 IOs for a total memory bandwidth of 48 GB/s. The GDDR5X DRAM relies on the quad data rate operation enabled by a phase-locked loop (PLL), a receiver with a pre-amplifier in a dual-regulation loop and a one-tap digital feedback equalizer (DFE). To support lower performance modes, an additional GDDR5-like operation is provided, which bypasses the PLL. The interface is realized on a conventional high-volume DRAM process to provide a cost-efficient, discrete package 8-Gb DRAM for high-performance graphic cards and compute applications.

A Glossary of Behavior Analytic Terms for Speech-Language Pathologists' Considerations for Augmentative and Alternative Communication

At its core, productive collaboration between speech-language pathologists and behavior analysts requires effective communication between both parties. Successful communication can be gained in par...

Simulator for analysis cyber threats to RFID based system

The paper addresses the issues of attacks in cyberspace from the local perspective of computer network and IoT devices of RFID based office system. The rapid development in IT technology has constantly brought out revolutionary changes in the area of office services. The very promising technology for automatic identification is RFID that has changed the manual scenario of office tasks to computerized automated services. However, RFID based systems are vulnerable to various cyberattacks, from simple passive eavesdropping to well-known denial of service (DoS). One of the methods for the analysis of threats is computer modelling and simulation. M&S gives the possibility of quantitative and qualitative analysis as well as forecasting. As a part of the work, the original Java-based discrete simulation package has been developed. The simulation model and relevant software was implemented to simulate DoS attack on a protected server in restricted access administrative office. In contrast to most of existing simulation tools in the field of cyberspace, the simulation package has been designed to model and simulate heterogeneous devices which behaviours might be modified by programming Groovy/Python scripts.

Lifetime Estimation of Discrete IGBT Devices Based on Gaussian Process

Discrete package insulated gate bipolar transistor (IGBT) devices are a popular choice for low-power converters. Although IGBT power modules used in high-power applications have recently been studied in the literature, there are major knowledge gaps regarding reliability and lifetime estimation of discrete devices. In this paper, on-state collector–emitter voltage drop $(V_{{\rm{ce}},{\rm{on}}})$ variations are characterized for discrete IGBT devices exposed to cyclic thermal stresses. Variations in $V_{{\rm{ce}},{\rm{on}}}$ are carefully identified and classified depending on different aging mechanisms, stress levels, and device structures. A probabilistic framework for remaining useful lifetime (RUL) estimation based on the knowledge obtained by accelerated aging experiments for real-time RUL estimation has been proposed. Specifically, the proposed model uses Gaussian process regression (GPR) for applying a Bayesian inference (BI) on RUL estimation of the device under test. Using BI reduces the uncertainty associated with RUL estimation and leads to more accurate results. This concept is also tested by comparing the classical maximum-likelihood estimation and GPR estimation results with the ones obtained by accelerated aging tests.

Power Semiconductor SMD Package Embedded in Multilayered Ceramic for Low Switching Loss

We propose a multilayered-substrate-based power semiconductor discrete device package for a low switching loss and high heat dissipation. To verify the proposed package, cost-effective, low-temperature co-fired ceramic, multilayered substrates are used. A bare die is attached to an embedded cavity of the multilayered substrate. Because the height of the pad on the top plane of the die and the signal line on the substrate are the same, the length of the bond wires can be shortened. A large number of thermal vias with a high thermal conductivity are embedded in the multilayered substrate to increase the heat dissipation rate of the package. The packaged silicon carbide Schottky barrier diode satisfies the reliability testing of a high-temperature storage life and temperature humidity bias. At 175 °C, the forward current is 7 A at a forward voltage of 1.13 V, and the reverse leakage current is below 100 μA up to a reverse voltage of 980 V. The measured maximum reverse current (IRM), reverse recovery time (Trr), and reverse recovery charge (Qrr) are 2.4 A, 16.6 ns, and 19.92 nC, respectively, at a reverse voltage of 300 V and di/dt equal to 300 A/μs.

Comparative Evaluation and Analysis of Gate Driver Impacts on a SiC MOSFET-Gate Driver Integrated Power Module

Abstract SiC MOSFET-gate driver integrated power module is proposed to provide ultra-low stray inductance compared to traditional TO-247 or TO-220 packages. Kelvin connection eliminates the common source stray inductance and zero external gate resistor enables faster switching. This module can be operated at MHz switching frequency for high power applications with lower switching losses than discrete packages. Two different gate drivers and two different SiC MOSFETs are grouped and integrated into three integrated power modules. Comparative evaluation and analysis of gate driver impacts on switching speed of SiC MOSFET is shown in detail. The paper provides an insight of the gate driver impacts on the device switching performance in an integrated power module.

Rapid methods for radionuclide contaminant transport in nuclear fuel cycle simulation

Nuclear fuel cycle and nuclear waste disposal decisions are technologically coupled. However, current nuclear fuel cycle simulators lack dynamic repository performance analysis due to the computational burden of high-fidelity hydrolgic contaminant transport models. The Cyder disposal environment and repository module was developed to fill this gap. It implements medium-fidelity hydrologic radionuclide transport models to support assessment appropriate for fuel cycle simulation in the Cyclus fuel cycle simulator.Rapid modeling of hundreds of discrete waste packages in a geologic environment is enabled within this module by a suite of four closed form models for advective, dispersive, coupled, and idealized contaminant transport: a Degradation Rate model, a Mixed Cell model, a Lumped Parameter model, and a 1-D Permeable Porous Medium model. A summary of the Cyder module, its timestepping algorithm, and the mathematical models implemented within it are presented. Additionally, parametric demonstrations simulations performed with Cyder are presented and shown to demonstrate functional agreement with parametric simulations conducted in a standalone hydrologic transport model, the Clay Generic Disposal System Model developed by the Used Fuel Disposition Campaign Department of Energy Office of Nuclear Energy.

A proposed underlying source of human error

Difficult tasks tend to increase response times and errors, but also, paradoxically, the more quickly we have to respond to something, the more likely it is that we will make an error. Although much-researched and discussed, the underlying reasons for these apparent connections and contradictions have never been satisfactorily explained. This paper proposes that cognitive information is processed in discrete packages so that, during decision making, the likelihood and type of error depends on the precise moment at which a decision is taken and the degree to which the decision is synchronous with package processing. By understanding how response times and error might be connected, we can make informed judgements about how one might affect the other. This offers the prospect of reducing human error, which is particularly important in safety critical environments, but which also has application for improving reliability across all human activity.

Towards prognostics and health monitoring: The potential of fault detection by piezoresistive silicon stress sensor

A piezoresistive silicon based stress sensor has been demonstrated successfully as an effective tool to monitor the stresses inside electronic packages during various production processes. More recently, the sensor has been evaluated as a sensor for Prognostics and Health Monitoring (PHM) systems. This paper presents a systematic approach that evaluates its performance from the perspective of failure mode detection. A detailed Finite Element method (FEM) model of existing test vehicles is created. The test vehicle consists of six DPAK (Discrete Package) power packages and three stress sensors. The results of simulation are verified by the signals obtained from the stress sensor as well as the supplementary warpage measurements. After inserting various failure modes into the model, statistical pattern recognition algorithms are implemented for fault detection and classification. The proposed technique can identify detectable failures during reliability testing by utilizing the database of stress sensor responses for healthy and unhealthy state. Thus, the results establish a baseline for the applicability of the piezoresistive stress sensor for an on-line monitoring PHM methodology.

Discrete Element Modeling for Sieve Analysis with Image-based Realistic Aggregates

Grain sizes play significant roles in determining internal structure and mechanical behaviors of a granular assembly. The main objectives of this research are to develop a numerical method for sieve analysis through an image-based discrete element modeling and apply the newly-developed method for analyzing aggregate particle sizes. The discrete element software package, PFC5.0 Suite, was employed to establish a virtual sieving testing method to determine aggregates grain size. X-ray Computed Tomography was employed to scan the selected individual aggregate particles. Then, a speciallydesigned discrete element model was created for the virtual sieve tests. Finally, three vibration patterns were considered to investigate their effects on the sieving analysis results. Through this research, the recommendations were made for aggregate sieve analysis.

A Pore-Scale Model for Quantifying Airflow Paths through Grain Bulks

Abstract. A commercial discrete element software package (PFC3D) was used to develop a model to simulate pore structures of grain beds. Based on the simulated structure of a grain bed, an algorithm reported in the literature was adopted and modified to determine airflow paths in the grain bed by treating the grain bed as a series of four-particle tetrahedrons. Critical characteristic parameters of the airflow path were predicted, including path length (tortuosities), width, and local turning angle (change in airflow direction at a location in the grain bed). The predicted tortuosities were in good agreement with the range of tortuosity values reported in the literature for porous beds consisting of spherical particles. The average path width was in the range of 0.83 to 5.93 mm. The local turning angles were mostly in the 0° to 10° range. Keywords: Airflow, Discrete element method, Grain bed, Pore structure, Tortuosity.

Aging Precursor Identification and Lifetime Estimation for Thermally Aged Discrete Package Silicon Power Switches

Thermal/power cycles are widely acknowledged methods to accelerate the package related failures. Many studies have focused on one particular aging precursor at a time and continuously monitored it using custom-built circuits. Due to the difficulties in taking sensitive measurements, the reported findings are more on the quantities requiring less sensitive measurements. In this paper, two custom-designed testbeds are used to age a number of power MOSFETs and insulated gate bipolar transistors. An automated curve tracer is utilized to capture parametric variations in I-V curves, parasitic capacitances, and gate charges at certain time intervals. The results suggest that the only viable aging precursors are the on-state voltage drop/on-state resistance, body diode voltage drop, parasitic capacitances, and gate threshold voltage for die attach solder and gate-oxide degradation mechanisms. Based on the experimental results, gate threshold voltage variation is empirically modeled to estimate the remaining useful lifetime of the switches experiencing gate oxide degradation. The model parameters are found by the least squares method applied to inliers determined by the random sample and consensus outlier removal algorithm.

What theory, for whom and in which context? Reflections on the application of theory in the development and evaluation of complex population health interventions

Recent years have seen a growing emphasis on the value of building and testing middle range theory throughout the development and evaluation of complex population health interventions. We agree that a coherent theoretical basis for intervention development, and use of evaluation to test key causal assumptions and build theory, are crucial. However, in this editorial, we argue that such recommendations have often been operationalised in somewhat simplistic terms with potentially perverse consequences, and that an uncritical assumption that an intervention explicitly based on theory is inherently superior carries significant risks. We first argue that the drive for theory-based approaches may have exacerbated a propensity to select ‘off-the-shelf’ theories, leading to the selection of inappropriate theories which distract attention from the mechanisms through which a problem is actually sustained. Second, we discuss a tendency toward over-reliance on individual-level theorising. Finally, we discuss the relatively slow progress of population health intervention research in attending to issues of context, and the ecological fit of interventions with the systems whose functioning they attempt to change. We argue that while researchers should consider a broad range of potential theoretical perspectives on a given population health problem, citing a popular off-the-shelf theory as having informed an intervention and its evaluation does not inherently make for better science. Before identifying or developing a theory of change, researchers should develop a clear understanding of how the problem under consideration is created and sustained in context. A broader conceptualisation of theory that reaches across disciplines is vital if theory is to enhance, rather than constrain, the contribution of intervention research. Finally, intervention researchers need to move away from viewing interventions as discrete packages of components which can be described in isolation from their contexts, and better understand the systems into which change is being introduced.

Production of Adjuvant-Loaded Biodegradable Particles for Use in Cancer Vaccines.

Immune adjuvants, such as ligands for pathogen-associated molecular patterns (PAMPs), have been showing promise in boosting immune responses to tumor associated antigens, and delivering these adjuvants as discrete packages is considered advantageous over delivery in soluble form. Here we describe in detail, methods for independently loading a range of adjuvants into polymer-based biodegradable particles. We also describe the means by which to characterize these particles with respect to adjuvant loading and release kinetics as well as in terms of particle size, shape, and zeta-potential. These adjuvant-loaded particles have the potential to be used in dendritic cell-based uptake experiments performed in vitro or to be used in preclinical cancer vaccine research applications where they can be co-delivered with antigen-loaded particles or some other vaccine component comprising antigenic material.

History and Recent Developments of Packaging Technology for SiC Power Devices

Packaging plays an important role to allow the full potential of silicon carbide devices to be realised. The physical properties of silicon carbide will allow devices to operate with junction temperatures well above 200 °C, but today standard-packaged SiC products are limited to a maximum junction temperature of 175 °C. The limitation lies in the packaging, because a power device package is a complex structure consisting of many components of different materials and with correspondingly different thermal properties. As such, the assembly technologies define both the performance and lifetime of discrete packages and power modules. In this paper we give an insight of packaging technology for SiC devices from the beginning in the mid-1980s through to the state-of-the-art of today. In addition, new packaging technologies to enable power SiC devices to operate up to 200 °C are discussed.

Digital Color Image Watermarking using DWT and SVD for Data Security

Now a day’s internet plays a vital role in carrying information from one place to another .This information which is transmitted is digital multimedia which include images audio and also video .Attacking of digital data is very easy and easily monitored by anyone through the internet .Therefore in order to protect these attacks several intellectual rights have been introduced nearly fifty years ago. This results in the evolution of digital watermarking. Watermarking of images can be done in various domains such as spatial domain, frequency domain, and wavelet domain. In watermarking is a technique of embedding a secret message in a cover message. When media is watermarked the secret message is usually a copyright message. Watermarking does discourages intellectual property theft and help us to prove ownership when such a theft occurs. This survey paper describes digital watermarking in detail and explains theory, techniques and its applications especially to digital libraries. This paper tells about digital image watermarking scheme with blind detection for copyright verification. The binary watermarks are embedded in the wavelet domain of an image using the discrete wavelet package transform (DWPT) and quantization of the selected dominant coefficients. In our algorithm largest value of coefficients is at same blocks of watermark embedding process will be selected during the watermark extraction. Therefore we doing need the original image for watermark extraction process. It is a blind detection technique. It saves time and space for transferring of original image respectively experimental result show that the proposed techniques are robust to Gaussian noise and jpg compression. These propose method is designed robust against these attacks and based on blind detection, Therefore it can be used in copyright verification effectively.

Parametric Estimate Cost of Wind Farms in Latin America and the Caribbean

In order to be able to carry out early studies of viability, to analyze variants and to make tests of sensibility to the projects of wind farms, in this work has been developed a mathematical model for a quick, economic way and with enough precision, determine the cost that will have the park later when it is built. The method receives the name of parametric estimate of the cost. It consists on mathematics relationships between the variables or controllers (drivers) of the cost of projects. Although in the independent evaluations, the results might not be as exact as in the discrete methods, it presents a high relative precision when they are compared alternative, and their property of continuity allow him to work inside a calculation algorithm for the analysis of variants and sensibility where the technical and economic variables of the project are involved. It was developed and evaluated for the countries of Latin America and the Caribbean by the particular characteristics that exposed in the work with regard to other regions of the world. Engineering today is not limited to the solution of problems in their respective fields of knowledge, but takes into account all the variables that can affect the application of solutions and development projects. One of those variables are the cost, which allows analysis of alternatives, take decisions and change solutions related to the project. This is because the effectiveness of the projects is usually evaluated in economic terms where costs and income are the key variables. It is almost impossible to separate the technical from the economic. The different elements that make up the cost of the life cycle of a project are well defined, and its calculation should not have difficulties if those costs are separately and performed with discrete values. The problem occurs when there is a need to establish the continuous relationship between the cost and the basic parameters of the process. When the independent variables and the cost are enlisted in a decision algorithm, analysis must be consistent with both. In practice, the determination of the cost of the investment or capital cost can be performed by two general procedures: step-by-step or discrete direct determination and the determination by some method of estimation. The discrete calculation of the cost of projects normally done by the sum of the individual costs of engineering, equipment, materials and work within the capital cost. The parties may vary in size and number from a few to hundreds or thousands of tasks or discrete work packages. This calculation isusually carried out by the contractor and accompanied by the programming of each activity. The result may be necessary if all the determinants of the cost are dominant but are laborious, time-consuming work and do not disclose the relationship between the technical parameters and cost. There are different methods of estimation of the capital cost, some of them can be applied during the early stages of the project in which only need to have an idea of the cost; others may be as accurate as the discrete calculation. This paper presents the methodology followed for the development of a mathematical model for parametric estimation of the cost of wind farms for the specific conditions of Latin America and the Caribbean.

Life on Earth is an individual

Life is a self-maintaining process based on metabolism. Something is said to be alive when it exhibits organization and is actively involved in its own continued existence through carrying out metabolic processes. A life is a spatio-temporally restricted event, which continues while the life processes are occurring in a particular chunk of matter (or, arguably, when they are temporally suspended, but can be restarted at any moment), even though there is continuous replacement of parts. Life is organized in discrete packages, particular cells and multicellular organisms with differing degrees of individuality. Biological species, too, have been shown to be individuals, and not classes, as these collections of organisms are spatio-temporally localized, restricted, continuous, and somewhat cohesive entities, with a definite beginning and end. Assuming that all life on Earth has a common origin, all living organisms, cells, and tissues descending from this origin exhibit continuity of the life processes at the cellular level, as well as many of the features that define the individual character of species: spatio-temporal localization and restriction, continuity, historicity, and cohesiveness. Therefore, life on Earth is an ontological individual. Independent origins of life will have produced other such individuals. These provisionally called 'life-individuals' constitute a category of organization of life which has seldom been recognized. The discovery of at least one independent life-individual would go a long way toward the project of the universality of biology.

Simulation of cable and wire waste separation process

Growth in the amount of waste containing non-ferrous metals leads to environmental pollution. Waste recycling is economically advantageous not only from an environmental standpoint. The problem is to separate the scrap components for further processing. The cheapest method is gravity separation in the air stream. The study found that the process efficiency and performance depend on the material looseness in the working space of the separator. The effect of this parameter is examined through numerical simulation using the discrete element method and GranularLux software package. This method allows exploring various process parameters in very small, discrete time periods, the impact of which is difficult to reveal in the field experiment. The theoretical basis of the method and the results of simulation of cable and wire waste separation process are presented. It is shown that simulation allows determining the rational looseness of scrap particles in the working space of the separator, which provides the required quality of separation products. The results can be used in the development of technology and equipment for waste separation into components. Waste recycling will reduce human impacts on the environment.

Embedded Die Packages and Modules for Power Electronics Applications

Packages and modules with embedded semiconductor dies are of interest for various application fields and power classes. First packages in the lower power range are available in volume production since almost six years. Recent developments focus on medium and higher power applications raging over 500W into the kW range. Different approaches are available to realize such packages and modules. This paper will give an overview and detailed description of the latest approaches for such embedded die structures. In common of all of these approaches, is the use of laminate based die embedding, which uses standard PCB manufacturing technologies. Main differences are the used base substrate, which can still be a ceramic (DBC), Cu leadframe or high current substrate. Examples for the different methods will be given. As the main part, this paper will describe concepts, which enable significant smaller form-factor of power electronics modules, thereby allowing for lower price, high reliability, capability of direct mounting on e.g. a motor so as to form one unit with the motor housing, wide switching frequency range (for large application field) and high power efficiency. The innovative character of this packaging concept is the idea to embed the power drive components (IGBTs, MOSFETs, diode) as thinned chips into epoxy-resin layer built-up and to realize large-area interconnections on both sides by direct copper plating the dies to form a conductor structure with lowest possible electrical impedance and to achieve an optimum heat removal. In this way a thin core is formed on a large panel format which is called Embedded Power Core. The paper will specifically highlight the first results on manufacturing an embedded power discrete package as an example of an embedded power core containing a thin rectifier diode. For module realization, the power cores are interconnected to insulated metal substrates (IMS) by the use of Ag sintering interconnection technologies for the final manufacturing of Power modules. The paper will elaborate on the sintering process for Power Core/IMS interconnections, the microscopically features of the sintered interfaces, and the lateral filling of the sintering gap with epoxy prepregs. Firstly, 500W power modules were manufactured using this approach. Reliability testing results, solder reflow testing, temperature cycling test and active power cycling, will be discussed in detail.