A clock power model to evaluate impact of architectural and technology optimizations

The clock distribution and generation circuitry forms a critical component of current synchronous digital systems and is known to consume at least a quarter of the power budget of existing microprocessors. We propose and validate a high level model for evaluating the energy dissipation of the clock generation and distribution circuitry, including both the dynamic and leakage power components. The validation results show that the model is reasonably accurate, with the average deviation being within 10% of SPICE simulations. Access to this model can enable further research at high-level design stages in optimizing the system clock power. To illustrate this, a few architectural modifications are considered and their effect on the clock subsystem and the total system power budget is assessed.     

On the stability of bilinear filters

We consider stability properties of discrete-time bilinear filters. Simple sufficient conditions are given for bounded-input bounded-output stability (with not necessarily zero initial conditions),l _p stability, and three other important types of stability. In particular, conditions are given under which asymptotically periodic inputs produce asymptotically periodic outputs with the same period.     

Branching competitive learning Network:A novel self-creating model

This paper presents a new self-creating model of a neural network in which a branching mechanism is incorporated with competitive learning. Unlike other self-creating models, the proposed scheme, called branching competitive learning (BCL), adopts a special node-splitting criterion, which is based mainly on the geometrical measurements of the movement of the synaptic vectors in the weight space. Compared with other self-creating and nonself-creating competitive learning models, the BCL network is more efficient to capture the spatial distribution of the input data and, therefore, tends to give better clustering or quantization results. We demonstrate the ability of the BCL model to appropriately estimate the cluster number in a data distribution, show its adaptability to nonstationary data inputs and, moreover, present a scheme leading to a multiresolution data clustering. Extensive experiments on vector quantization of image compression are given to illustrate the effectiveness of the BCL algorithm.     

Some Controversies Regarding the Teaching of Psychoanalysis: Comment on Mendelsohn (2005).

Eric Mendelsohn (2005) emphasizes the value of analysts' learning from patients, optimal ways of working with them psychoanalytically. He exhibits a healthy skepticism about traditional methods of learning to be a psychoanalyst, with particular caution about identifying with strong teachers or all-too-clear systems of thought. He fears this may inadvertently create a kind of fundamentalism and a parallel loss of analytic spontaneity. The author agrees with much of Mendelsohn's thesis but has some concern about going too far in the direction of promoting spontaneity, as this ethos too can reflect an inclination to idealize charismatic teachers who specialize in breaking the rules. He suggests that an emphasis on analytic spontaneity is best acquired after some reasonable period of working as at least a somewhat reserved and cautious young analyst. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Design and Expected Performance of GISMO-2, a Two Color Millimeter Camera for the IRAM 30 m Telescope

We present the main design features for the GISMO-2 bolometer camera, which we build for background-limited operation at the IRAM 30 m telescope on Pico Veleta, Spain. GISMO-2 will operate simultaneously in the 1 and 2 mm atmospherical windows. The 1 mm channel uses a \(32 \times 40\) TES-based backshort under grid (BUG) bolometer array, the 2 mm channel operates with a \(16 \times 16\) BUG array. The camera utilizes almost the entire full field of view provided by the telescope. The optical design of GISMO-2 was strongly influenced by our experience with the GISMO 2 mm bolometer camera, which is successfully operating at the 30 m telescope. GISMO is accessible to the astronomical community through the regular IRAM call for proposals.     

High-Resolution Kaonic-Atom X-ray Spectroscopy with Transition-Edge-Sensor Microcalorimeters

We are preparing for an ultra-high resolution X-ray spectroscopy of kaonic atoms using an X-ray spectrometer based on an array of superconducting transition-edge-sensor microcalorimeters developed by NIST. The instrument has excellent energy resolutions of 2–3 eV (FWHM) at 6 keV and a large collecting area of about 20 mm \(^2\) . This will open new door to investigate kaon-nucleus strong interaction and provide new accurate charged-kaon mass value.     

Soft error modeling and analysis of the Neutron Intercepting Silicon Chip (NISC)

Soft errors are transient errors caused due to excess charge carriers induced primarily by external radiations in the semiconductor devices. Soft error phenomena could be used to detect thermal neutrons with a neutron monitoring/detection system by enhancing soft error occurrences in the memory devices. This way, one can convert all semiconductor memory devices into neutron detection systems. Such a device is being developed at The Pennsylvania State University and named Neutron Intercepting Silicon Chip (NISC). The NISC is envisioning a miniature, power efficient, and active/passive operation neutron sensor/detector system. NISC aims to achieve this goal by introducing ¹⁰B-enriched Borophosphosilicate Glass (BPSG) insulation layers in the semiconductor memories. In order to model and analyze the NISC, an analysis tool using Geant4 as the transport and tracking engine is developed for the simulation of the charged particle interactions in the semiconductor memory model, named NISC Soft Error Analysis Tool (NISCSAT). A simple model with ¹⁰B-enriched layer on top of the lumped silicon region is developed in order to represent the semiconductor memory node. Soft error probability calculations were performed via the NISCSAT with both single node and array configurations to investigate device scaling by using different node dimensions in the model. Mono-energetic, mono-directional thermal and fast neutrons are used as the neutron sources. Soft error contribution due to the BPSG layer is also investigated with different ¹⁰B contents and the results are presented in this paper.     

Design of kilogram mass scale TES for the Cryogenic Dark Matter Search

Recently there has been much interest in the direct detection of the dark matter candidates known as WIMPs. We are developing very sensitive detectors based on phonon detection with transition edge sensors on silicon substrates. These detectors will be deploy ed as part of the Cryogenic Dark Matter Search in collaboration with the Center for Particle Astrophysics. As we extend this technology to practical WIMP searches we will need much higher mass scale detectors. We have demonstrated detectors on 500 µm substrates. To reach the kilogram mass scales we need to pattern wafers that are an order of magnitude thicker with a detector that is at least two orders of magnitude more sensitive. Progress is reported on both these areas and a detector design is discussed.     

Sampling Rate Evaluation Of NO2 Badge: (I) In Indoor Environments

The sampling rate of a nitrogen dioxide (NO²) passive sampling badge was evaluated in indoor environments including an unoccupied research house, residential houses, and an office. Measurements from the NO² badges were compared with those of a chemiluminescent analyzer the EPA reference method, by placing them near to the sample inlet of the chemiluminescent analyzer In this study, we used a new sampling rate for the NO² badge placed in indoor environments (an overall mass transfer coefficient of 0.10 cm/s) smaller than the rate previously reported for the badge when used outdoors. The new rate provides more accurate measurements of NO, concentrations in indoor environments. Indoor NO² concentrations were also measured with the NO² badges exposed to a constant wind velocity provided by a wind tunnel. Since the measurements of the badge with a constant wind velocity agreed well with the reference method, the badges could be assumed to be a secondary reference measurement. With the badges used as the secondary reference measurement, we developed a portable wind tunnel to evaluate a personal exposure measurement by the badge. The results are presented in Environment International (Lee et al., 1993). Precision of the badge measurements was as good as an intraclass correlation coefficient of 0.9779. It was determined that placement of the badge should be at least 10 cm out from an indoor wall surface to avoid undersampling due to NO² gradients near the surface.