Moving object detection with laser scanners

The detection and tracking of moving objects is an essential task in robotics. The CMU‐RI Navlab group has developed such a system that uses a laser scanner as its primary sensor. We will describe our algorithm and its use in several applications. Our system worked successfully on indoor and outdoor platforms and with several different kinds and configurations of two‐dimensional and three‐dimensional laser scanners. The applications vary from collision warning systems, people classification, observing human tracks, and input to a dynamic planner. Several of these systems were evaluated in live field tests and shown to be robust and reliable. © 2012 Wiley Periodicals, Inc.     

Elastic property prediction of single-walled carbon nanotube buckypaper/polymer nanocomposites: stochastic bulk response modeling

In this study, we investigated the statistical relationship between nanostructure variations of carbon nanotube buckypaper-polymer (BPP) composites and their resulting elastic properties. A statistical simulation was developed to predict the elastic properties of a single-layer BPP lamina and extrapolated to the resultant bulk composite part. The stochastic characteristics of BPP composite nanostructure were quantified from experimental observations and used to generate the input for each simulation set performed. The Mori-Tanaka method was used to calculate the stiffness tensor within the buckypaper-polymer region, and a Monte-Carlo simulation was applied to generate the probability distribution for the effective stiffness tensor within each BPP lamina. Classical laminate theory was then employed to predict the effective elastic response for a multi-layered BPP composite laminate. The theoretical predictions were compared with experimental data, and the resulting trends for the effective tensile modulus between experimental and theoretical corresponded well with each other.     

Yield and Textural Characteristics of Panela Cheeses Produced with Dairy‐Vegetable Protein (Soybean or Peanut) Blends Supplemented with Transglutaminase

The study evaluated panela cheeses made from dairy‐plant protein blends, using soybean or peanut protein isolates, supplemented with transglutaminase (TG). Plant proteins were isolated using an alkaline extraction method followed by acid precipitation, and added to the dairy system in order to increase 50% or 100% the protein concentration. The total protein extraction for peanut and soybean isolates was 30.3% and 54.6%, respectively (based on initial protein content of sources), and no impairment of their essential amino acid profile was detected. Cheeses supplemented with TG and soybean showed the highest moisture and crude yield (>67.8% and 20.7%, respectively), whereas protein content was higher in the peanut isolate—added samples without TG (>67.4%). Cheese solids yield (ratio between final and initial solids) was higher for treatments with TG and 100% of plant protein addition (>50.7%). Regarding texture, 4 parameters were measured: hardness, cohesiveness, chewiness, and springiness. All cheeses containing soybean isolates and TG presented the highest chewiness and cohesiveness values, similar to those of the control treatment. Springiness was similar for all treatments, but hardness was higher in cheeses prepared with the peanut protein isolate added with TG. From these results it can be concluded that panela cheeses can be elaborated following a traditional procedure, but with the addition of soybean or peanut protein to the dairy ingredients. Cheeses containing these protein isolates showed higher protein than the milk control cheese and similar textural characteristics.     

The role of project management in university computing resource departments

Today’s businesses have learned the value of incorporating formal project management practices and tools. However, the drivers that have pushed businesses to adopt them have not had as large an impact on institutions of higher education. This paper investigates the acceptance and usage of formal project management techniques by university information technology departments. Results of a mail survey determined that current university IT departments lag behind their business peers in the adoption and usage of project management practices and tools. Additionally, it was discovered that the most utilized project management function by the academic institutions was project planning.     

Managing the integrity of design data generated by multiple applications: The principle of patching

The purpose of this work is to develop automatic methods of semantic integrity maintenance, in support of concurrent engineering. Semantic integrity relations in any final engineering design are built up incrementally, through the use of different computer applications. Here, the structure of these integrity relations are formalised for representation within a database. When changes to a design have to be made, they can invalidate integrity relations in other parts of the design. Formal methods are defined for identifying what data and integrity relations are invalidated by any change. Methods for making changes that minimise re-design are described and formalised. Opportunities for using semantic integrity to assess progress on a design are reviewed.Research supported by NSF grant IRI-9319982.     

An Accurate Transient Analysis of High-Speed Package Interconnects Using Convolution Technique

An accurate transient analysis of a package interconnect requires the modeling and analysis of conductor and dielectric losses, as well as other high-frequency effects of 3D structures. The skin effect and dispersion of interconnects are more accurately modeled in frequency domain. Consequently, an accurate time-domain simulation of such a system is only possible using convolution techniques. Although the convolution method is well understood, the application of windowing for frequency-dependent interconnect analysis is less so. In this paper, we present the practical considerations of window selection and its application to improve the accuracy of convolution simulators. We introduce the Tukey window and study the tradeoff between how smoothly data can be set to zero to avoid aliasing and suppress ripples and how much information tapering will discount at the edge of the window in order to obtain meaningful results. The bandlimiting effects of the Tukey window and other well-known windows are also compared. Finally, to verify the validity and accuracy of the proposed method, a wirebond PBGA package and a PCB-connector system are analyzed using the scattering parameters obtained from simulation and measurement, respectively.     

电源电子技术在降低能耗中的角色

全世界对能源消耗的关注日渐增加。作为减少能源消耗的两种方式，能源节省需要个人的自觉性加社会决策，而能效提升就纯粹是一个技术问题。美国使用的电能中的3％在电子电源转换过程中耗散为热量。因此电源电子产业，包括半导体公司、电源公司和终端产品制造商正在努力使这些损耗减少一半。他们所采用的方式就是提升大批量消费电子产品中的电源转换效率并降低待机能耗。     

Navigating the Next-Generation Application Architecture

In today's Internet environment, hyperconnectivity and new and complex technologies require a shift from individualized proprietary enterprise applications to a more open and dependent world of cloud computing. This article identifies changes IT professionals must understand to make the necessary adjustments to practices in today's evolving development space.     

Structural changes and Raman analysis of single-walled carbon nanotube buckypaper after high current density induced burning

Single-walled carbon nanotube (SWCNT) buckypaper (BP) was exposed to high temperatures with electrical current-driven thermal heating either in the air or a vacuum. High electrical currents generate Joule heating and then cause breakdown of the BP in the air at over 400 °C due to rapid oxidation. In the vacuum, electrical resistive heating can generate temperatures of more than 2000 °C for the samples. Structural changes of SWCNTs after electrical current heating were observed using electron microscopy and Raman spectra. After breakdown of BP, the disorder-induced D-band increased and a smaller diameter related radial-breathing mode was reduced in the high temperature region. Structural transformations of SWCNT to other carbon nanostructures were observed after current-driven high-temperature treatment in the vacuum. In addition, surface-enhanced Raman scattering with intensity enhancement more than ten times was observed in the BP with agglomerated Fe or Ti particles.