Innovative Solutions in Induction Heating for Better Energy Efficiency:Presentation of ISIS Project

The Energy Climate Package is the EU response to the Global Warming Challenge.Induction heating processes can contribute to the energy saving goal:20%saving within 2020.European induction manufacturer already propose many efficient solutions at industrial scale.To improve induction devices for an always better energy efficiency,EDF R&D set up a French cooperative project called ISIS with a financial support of the French National Research Agency.Its objective is to promote induction heating as Best Available Technology(BAT)and to develop innovative solutions to increase its efficiency.The ISIS innovations concern the electroheat conversion of induction devices(auto-adaptive multi-coil power supply,low losses coils)and the recovering of fatally lost energy.This paper shows the mid-term results of this project.Firsts control algorithms were successfully tested on a 100 kW 3-coil power supply.A homogenization technique is proposed to model a multi-strand coil.A heat recovery test bench is build and equipped with a PFC control loop to fit with the production fluctuations.     

Evaluating the market transformation impacts of a DSM program in the Province of Quebec

In 2006, Hydro-Québec introduced a large DSM program on the market to promote the adoption of compact fluorescent lamps in Québec households. After 3 years of program implementation, there was significant indication on the part of market actors that the promotional campaign component was quite effective in transforming the Québec market. Hydro-Québec therefore decided to modify its approach to program evaluation to include the quantification of market effects. Econoler led a team including American partners, Opinion Dynamics Inc. and Megdal & Associates to conduct an evaluation of program impacts on market transformation. An evaluation strategy was designed where different research tools would be integrated to determine market evolution over the two previous years. Each research method was used to determine an estimate of program impacts, then triangulated with other approaches to determine the most appropriate impact evaluation method regarding the Hydro-Québec program. Research efforts included a non-participant survey, interviews at manufacturer headquarters across Canada, interviews with banner distributor representatives across Canada, the collection of sales and market share data from manufacturers and retailers as well as secondary research to identify other players that could influence the market. The evaluation revealed that savings of 168 GWh could be attributed to direct and indirect impacts of the program for the 2006–2007 period.     

Some features of anisothermal solid-state transformations in alloy 718

This paper presents an attempt to use differential thermal analysis to study anisothermal precipitation of both the stable delta and the metastable gamma-second phases during cooling of alloy Inconel 718. Observation of the samples by scanning and transmission electron microscopy was carried out to identify the thermal arrests observed upon cooling. When the upper temperature of the cycle is above the solvus of the delta phase, a clear peak is observed that could be related to precipitation of gamma-second for all the cooling rates used in the present work. When this temperature is below the delta solvus, no thermal arrest can be observed, while when it is close to it two faint peaks were noted and associated with stable and metastable precipitation. The most striking result was that dissolution of the metastable gamma-second phase during the heating stage was found to proceed heterogeneously in the material, and this affected reprecipitation of the phases upon subsequent cooling.     

CD95 (Fas/Apo-1) as a receptor governing astrocyte apoptotic or inflammatory responses: a key role in brain inflammation?

Astrocytes are a major cellular component of the brain that are capable of intense proliferation and metabolic activity during diverse inflammatory brain diseases (such as multiple sclerosis, Alzheimer's dementia, tumor, HIV encephalitis, or prion disease). In this biological process, called reactive gliosis, astrocyte apoptosis is frequently observed and could be an important mechanism of regulation. However, the factors responsible for apoptosis in human astrocytes are poorly defined. Here, we report that short term cultured astrocytes derived from different brain regions express significant levels of CD95 at their surface. Only late passage astrocytes are sensitive to CD95 ligation using either CD95 mAb or recombinant CD95 ligand. Blocking experiments using caspase inhibitors with different specificities (DEVD-CHO, z-VAD-fmk, and YVAD-cmk), an enzymatic activity assay, and immunoblotting show that CPP32/caspase-3 play a prominent role in CD95-induced astrocyte death. In contrast, early passage astrocytes are totally resistant to death, but a significant increase in astrocytic IL-8 secretion (p < 0.001, by Wilcoxon's test for paired samples) is observed after CD95 triggering. Production of IL-8 contributes to the resistance of astrocytes to CD95 ligation. Furthermore, in the presence of IFN-gamma, resistant astrocytes became sensitive to CD95-mediated death. These data suggest that microenvironmental factors can influence the consequences of CD95 ligation on astrocytes. Therefore, we propose that CD95 expressed by human astrocytes plays a pivotal role in the regulation of astrocyte life and death and may be a key factor in inflammatory processes in the brain, such as reactive gliosis.     

Expanding Disk Rain Sensor Performance and Potential Irrigation Water Savings

Rain sensors (RSs) appear to be a useful tool for water conservation at a relatively low cost. However, little evidence related to RS performance and/or reliability exists. The objectives of this experiment were to: (1) evaluate two RS types with respect to the following: Accuracy of their set point, number of irrigation cycles bypassed, and duration in bypass mode; (2) quantify the amount of water that RSs could save; and (3) estimate their payback period. Mini-click (MC) and wireless rain-click (WL) rain sensor models were monitored. For the WL treatment, the dry-out ventilation windows were set half open, and for the MC treatments, rainfall set points of 3, 13, and 25?mm were established. On average, all treatments responded close to their set points with the WL, 3?mm MC, 13?mm MC, and 25?mm MC treatments averaging 1.4, 3.4, 10.0, and 24.5?mm, respectively. However, some replicates showed variable behavior. The number of times that these sensors shut off irrigation (81, 43, 30, and 8 times, respectively) was inversely proportional to the magnitude of their set point, with potential water savings following a similar trend. Where water costs exceed $0.53 per cubic meter ($2.00 per thousand gallons), the payback period is less than a year for WL and MCs set at 13?mm or less.     

A statistical analysis of void size distribution in a simulated narrowly graded packing of spheres

The void microstructure of a simulated packing of polydisperse spheres has been investigated by means of a radical Delaunay tessellation. We have focused on creating sphere packings by mimicking processes involved in the construction of embankment dams: the polydisperse spheres are collectively released under gravity and denser states are mainly obtained by means of shearing cycles. This study has been performed on a narrowly graded material for four porosities ranging from 0.42 to 0.36. The void structure is quantified in terms of probability density functions of pore and constriction sizes, cumulative distributions and connectivity functions. We emphasize the implications of the sample construction technique on the geometric packing arrangements, among them a well disordered medium where tetrahedra remain the most represented unit void structure. We point out that when porosity decreases, void distributions become narrower but the initial structure is never destroyed. Nevertheless, the densification modifies significantly the computed mean void quantities. In this study, usual geometric arrangements obtained for very dense materials are not encountered.     

Inertial Impactors to Measure Aerodynamic Diameters of Man-Made Organic Fibers

It is widely accepted that the aerodynamic diameter of a particle is one of the main factors that determines particle deposition into the human respiratory system. The determination of aerodynamic diameter of spheres or near spherical objects is routinely accomplished using impactors. The aerodynamic diameter of man made organic fibers (MMOF), on the other hand, has not traditionally been measured using impactors, because fibers of the same cross section may have different lengths and a variety of shapes (straight, curved, etc.) for each length. The aerodynamic size of the fibers is thus a function of fiber orientation. Single and multiple stage impactors have been developed, calibrated, and validated specifically for the determination of the aerodynamic diameter of large fibers with circumscribed diameters between 20 and 35 w m and an aspect ratio ranging from subfiber lengths (aspect ratio < 3) up to 40. The impactor allows measurements of the aerodynamic diameter of cellulose acetate fibers released during mechanical smoking of cigarettes. The performance characteristics were evaluated by spherical particles of known diameters, fibers of known length and diameter, and computational fluid dynamic calculations. Our methodology has shown that inertial impactors can be used to determine the aerodynamic diameter of large cellulose acetate fibers.     

Stacked inverted top-emitting green electrophosphorescent organic light-emitting diodes on glass and flexible glass substrates

Stacked inverted top-emitting green electrophosphorescent organic light-emitting diodes (OLEDs) are demonstrated on glass and flexible glass substrates. A single-unit OLED is shown to have a current efficacy of 46.8 cd/A at a luminance of 1215 cd/m². When two of these OLEDs are stacked, the double-unit OLED exhibits a current efficacy more than twice that of the single-unit OLED, with a current efficacy of 97.8 cd/A at a luminance of 1119 cd/m². With the addition of an optical outcoupling layer of N,N′-Di-[(1-naphthyl)-N,N′-diphenyl]-1,1′-biphenyl)-4,4′-diamine (α-NPD) on top of the semitransparent gold anode, the double-unit stacked OLED achieves a maximum current efficacy of 205 cd/A at a luminance of 103 cd/m², maintaining a high current efficacy of 200 cd/A at a luminance of 1011 cd/m². These stacked inverted OLED combine the advantages of inverted OLEDs with the benefits of having a stacked architecture.     

Wireless Andrew: Building a High Speed, Campus-Wide Wireless Data Network

Carnegie Mellon University (CMU) has a major program to create a high speed wireless network, known as Wireless Andrew. The first Phase of this network has been operational for over a year and the second Phase, to upgrade this to IEEE 802.11 standard technology, has begun. The Wireless Andrew network uses wireless local area network technology, utilizing spread spectrum in the ISM band. The purpose is not only to support wireless research but also to create a campus-wide mobile computing laboratory.The paper shows the challenge of designing and managing large scale wireless networks. The examples show the differences experienced in wireless versus wireline networks due to the nature of mobility versus static components, the nature of RF propagation versus wireline connection, and the difference in sophistication of tools because of the different place in the product development cycle. The paper describes the lessons learned at completion of the first phase including: installation design issues, issues of RF interference and data throughput, the unique problems of wireless network management, and the release of the system. The paper goes on to describe lessons learned during the first year of operation of the research network. It then discusses experience so far in Phase Two, to create an operational utility for use of all students, faculty, and staff for educational, research, and administrative applications.