CTL and Its Usage in the EDA Industry

The Core Test Language, originally developed within the IEEE 1500 development working group but later spun out as an independent standard, specifies the standardized language in which core test information for both wrapped and still-to-be-wrapped cores is described.     

Annealing temperature dependence of TiB2 schottky barrier contacts on n-GaN

The annealing temperature (25–700°C) dependence of Schottky contact characteristics on n-GaN using a TiB₂/Ti/Au metallization scheme deposited by sputtering is reported. The Schottky barrier height increased from 0.65 to 0.68 eV as the anneal temperature was varied from 25°C to 350°C and decreased to 0.55 eV after annealing at 700°C. The barrier height showed no measurable dependence on measurement temperature up to 150°C. The elemental profile obtained from samples annealed at 350°C showed limited Ti diffusion from the elemental Ti layer into the gold layer. Annealing at 700°C produced significant out-diffusion of this layer, while the TiB₂ layer retained its stability. These contacts show promise for applications requiring good thermal stability, such as power amplifiers, but much more work is needed to establish their long-term reliability. In addition, TiB₂ has a strong propensity for oxidation, and it is imperative that overlayers such as Au be deposited in the same deposition chamber.     

Process Cheese: Scientific and Technological Aspects—A Review

ABSTRACT: Process cheese is produced by blending natural cheese in the presence of emulsifying salts and other dairy and nondairy ingredients followed by heating and continuous mixing to form a homogeneous product with an extended shelf life. Extensive research on the important physicochemical and functional properties associated with process cheese and the various physicochemical, technological, and microbiological factors that influence these properties has resulted in process cheese being one of the most versatile dairy products with numerous end‐use applications. The present review is an attempt to cover the scientific and technological aspects of process cheese and highlight and critique some of the important research findings associated with them. The 1st objective of this article is to extensively describe the physicochemical properties and microstructure, as well as the functional properties, of process cheese and highlight the various analytical techniques used to evaluate these properties. The 2nd objective is to describe the formulation parameters, ingredients, and various processing conditions that influence the functional properties of process cheese. This review is primarily targeted at process cheese manufacturers as well as students in the field of dairy and food science who may want to learn more about the scientific and technological aspects of process cheese. The review is limited to the relevant research associated with process cheeses as defined by the U.S. Code of Federal Regulations and does not cover imitation and substitute cheeses.     

Blood lead levels in primary school children in Trinidad and Tobago

This study is the first national baseline survey of blood lead levels (BLLs) conducted on primary school children (ages 5-7 years) in Trinidad and Tobago. A total of 1,761 students from 61 schools participated in the study over a 3-month period. Measurements of capillary BLLs were assessed as well as responses to a risk assessment questionnaire. BLLs ranged from <1 microg/dL to 28.6 microg/dL with a geometric mean of 2.8 microg/dL, which compared favourably with results from the U.S. 1991-94 National Health and Nutrition Examination Survey. Fifteen (0.9%) children had a BLL>or=10 microg/dL (10.8-28.6 microg/dL) of which three (0.2%) met the U.S. criteria for lead poisoning (BLL>or=20 microg/dL). Further environmental investigations are required to identify source(s) of lead exposure in cases with high BLL.     

Effective time averaging of multiplexed measurements: a critical analysis

Multiplexing and time averaging of signal are effective noise reduction protocols applied in many analytical measurement systems. The efficacy of these protocols may be reduced by random occurrences of high-magnitude noise that do not conform to the statistical distribution of noise for all other measurements in the data set. This high-magnitude noise, which may have an insignificant probability of occurrence for a single measurement, almost certainly affects data collected in a multichannel, multiplexed modality, such as Fourier transform infrared (FT-IR) spectroscopic imaging employing focal plane array detectors. To recover time-averaging advantages in these cases, we present a general coaddition method that uses two statistical measures, the mean and median of the ensemble of measurements of a signal, to obtain a better estimate of the true signal than that estimated by time averaging alone. This method, termed median filtered time averaging, is shown to be an effective noise removal procedure for FT-IR imaging data. The effects of noise removal on time averaging and multiplexing are examined theoretically and are demonstrated for hyperspectral infrared microspectroscopic imaging data obtained from human skin biopsies by using a rapid data acquisition procedure.     

Electrostatic control of ions and molecules in nanofluidic transistors

We report a nanofluidic transistor based on a metal-oxide-solution (MOSol) system that is similar to a metal-oxide-semiconductor field-effect transistor (MOSFET). Using a combination of fluorescence and electrical measurements, we demonstrate that gate voltage modulates the concentration of ions and molecules in the channel and controls the ionic conductance. Our results illustrate the efficacy of field-effect control in nanofluidics, which could have broad implications on integrated nanofluidic circuits for manipulation of ions and biomolecules in sub-femtoliter volumes.     

Phase change microvalve for integrated devices

An active microvalve that uses a meltable piston in place of a conventional solid material to obstruct fluid flow in a microfluidic channel has been developed. This phase change valve is simple to operate and requires no additional fabrication steps. The valve is inherently latched, reusable, and leak-proof (to at least 250 psi) and can be electronically addressed using resistive heaters. The valve has been characterized for a range of operational parameters that will serve as a design guide. For the designs tested, piston displacements of 5 mm or more in 1 s have been achieved. Valves 1.4 mm in length in a 50 microm x 200 microm channel have been integrated on a biochemical reaction device, and successful DNA amplification using PCR has been achieved. The phase change valve can be easily implemented in an array format that can be used to realize complex microfluidic circuits.     

Detection of basal cell carcinoma using electrical impedance and neural networks

Variations in electrical impedance over frequency might be used to distinguish basal cell carcinoma (BCC) from benign skin lesions, although the patterns that separate the two are nonobvious. Artificial neural networks (ANNs) may be good pattern classifiers for this application. A preliminary study to show the potential of neural networks to distinguish benign from malignant skin lesions using electrical impedance is presented. Electrical impedance was measured in vivo from 1 kHz to 1 MHz at five virtual depths on 18 BCC and 16 benign or premalignant lesions. A feed-forward neural network was trained using back propagation to classify these lesions. Two methods of preprocessing were used to account for the impedance of normal skin and the size of the lesion, one based on estimating the impedance of the lesion relative to adjacent normal skin and one based on estimating the impedance of the lesion independent of size or surrounding normal skin. Neural networks were able to classify measurements in a test set with 100% accuracy for the first preprocessing technique and 85% accuracy for the second. These results indicate electrical impedance may be a promising clinical diagnostic tool for basal cell carcinoma or other forms of skin cancer.     

Collaboration in Indian physics: A case study of the macro and micro parametrization of sub-disciplines (1800–1950)

The decade beginning 1920 is an important watershed in the history of physics in modern India. This is evident from the bibliometric data available on the publications in physics between 1800 and 1950. The paper studies the evolution of collaboration in four subdisciplines of physics during this period. In order to do so, two sets of measures of research collaboration have been employed. The collaboration index and collaboration coefficient have been calculated for the sub-disciplines. As far as the micro-parametrization of the discipline is concerned, collaboration measures developed by Egghe are obtained for the research careers of four leading Indian physicists, who were responsible for the institutionalization of physics research in India. In the present case the role of individuals responsible for the institutionalization of physics research is seen to be germane to the explosion of the number of publications in the 1920s. At the conjucture of the history of science and scientometrics, it is evident how the former can endow the latter with a modality of explanation; further, it is evident how scientometrics can inform the efforts of historians of science.     

Dynamically mapping tasks with priorities and multiple deadlines in a heterogeneous environment

In a distributed heterogeneous computing system, the resources have different capabilities and tasks have different requirements. To maximize the performance of the system, it is essential to assign the resources to tasks (match) and order the execution of tasks on each resource (schedule) to exploit the heterogeneity of the resources and tasks. Dynamic mapping (defined as matching and scheduling) is performed when the arrival of tasks is not known a priori. In the heterogeneous environment considered in this study, tasks arrive randomly, tasks are independent (i.e., no inter-task communication), and tasks have priorities and multiple soft deadlines. The value of a task is calculated based on the priority of the task and the completion time of the task with respect to its deadlines. The goal of a dynamic mapping heuristic in this research is to maximize the value accrued of completed tasks in a given interval of time. This research proposes, evaluates, and compares eight dynamic mapping heuristics. Two static mapping schemes (all arrival information of tasks are known) are designed also for comparison. The performance of the best heuristics is 84% of a calculated upper bound for the scenarios considered.