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.     

Assessing the tribocorrosion behaviour of Cu and Al by electrochemical impedance spectroscopy

This study is focused on the interests and limits of Electrochemical Impedance Spectroscopy, to establish the electrochemical behaviour of a tribosystem between Cu and Al, in acid solution. The calculated capacitance, in high-frequency range, partially allows understanding the double layer state of body in the contact. The Potential of Zero Charge (PZC) was calculated for Cu sample and it was associated with a potential range for Al. PZC value of each material is discussed as a key parameter of sliding contact. During tests of wear, the EIS results are related to the evolution of adsorbed water molecules.     

On modeling the irregular fluctuations in microbial counts

Daily or other periodic microbial counts in many foods, particularly ground meats, poultry, and raw milk, show an irregular fluctuating pattern. The cause of the fluctuations is the interplay of many random factors that tend to promote or inhibit microbial growth. Therefore, the actual size of a microbial population can vary randomly around a typical level or around a trend determined, for example, by seasonal variations or changing sanitary conditions. Fluctuations around a fixed level can often be modeled as a sequence of independent counts having a lognormal or other parametric distribution. The independence of the counts and the type of distribution can be established by standard statistical tests. Once selected, the distribution function can be used to estimate the probability of encountering a population in any given size range. The model can be modified to describe sequences that include zero counts, which are the result of the organisms' absence, or of the failure of the method to detect them. In the case of fluctuations around a trend, a modified version of the model can be used to estimate the probability of deviations from the trend. A more thorough modification is required in order to account for fluctuating patterns that include outbursts of appreciable duration, like those caused by massive contamination of a water reservoir.     

Effects of forage particle size and grain fermentability in midlactation cows. I. Milk production and diet digestibility

Our study investigated the effects of, and interactions between, level of dietary ruminally fermentable carbohydrate (RFC) and forage particle size on milk production, nutrient digestibility, and microbial protein yield for dairy cows fed one level of dietary NDF. Eight cows (61 days in milk) were assigned to four treatments in a double 4 x 4 Latin square. Treatments were arranged in a 2 x 2 factorial design; finely chopped alfalfa silage (FS) and coarse alfalfa silage (CS) were combined with concentrates based on either dry cracked shelled corn (DC; low RFC) or ground high-moisture corn (HMC; high RFC). Diets were fed ad libitum as a total mixed rations with a concentrate to forage ratio of 61:39. Diets based on DC had a predicted NEL content of 1.73 Mcallkg dry matter (DM), while HMC diets contained 1.80 Mcal/kg DM. Diets averaged 18.7% CP, 24.0% NDF, 18.3% ADF, and 27.4% starch on a DM basis. Mean particle size of the four diets was 6.3, 2.8, 6.0, and 3.0 mm for DCCS, DCFS, HMCCS, and HMCFS, respectively. Increasing level of RFC decreased dry matter intake (DMI) from 25.0 to 23.8 kg/ d and organic matter intake from 22.3 to 21.1 kg/d, but intake was not affected by particle size. Milk production averaged 44.0 and 26.8 kg/d solids corrected milk (SCM) and was not affected by diet, but increasing level of RFC tended to increase milk yield. Efficiency of milk production, expressed as SCM/DMI, increased from 1.06 to 1.14 when level of RFC was increased. Milk composition or yield of milk components was not affected by diet, and averaged 3.53% fat, 3.11% protein, 1.55 kg/d fat, and 1.36 kg/d protein. Total tract digestibility of DM and OM increased from 71.4 to 73.0% and 72.4 to 76.1% for DM and OM, respectively, when level of RFC was increased. Total tract digestibility of fiber was unaffected by diet, but total tract starch digestibility increased from 93.1 to 97.4% when HMC replaced DC. Total urinary excretion of the purine derivatives uric acid and allantoin increased from 415 to 472 mmol/d when level of RFC was increased, and calculated microbial N supply increased from 315 to 365 g/d. When expressed as per kilogram of digestible OMI, increasing level of RFC tended to increase microbial N supply (20.4 vs. 22.2 g/kg). Cow productivity was not affected by forage particle size and ruminally fermentable carbohydrates in this study.     

The frequency structure of one-dimensional occluding image signals

We present a theoretical investigation of the frequency structure of 1D occluding image signals. We show that image signal occlusion contains relevant information which is most easily extractable from its representation in the frequency domain. For instance, the occluding and occluded signal velocities may be identified as such and translucency phenomena may be understood in the terms of this theoretical investigation. In addition, it is found that the structure of occluding 1D signals is invariant under constant and linear models of signal velocity. This theoretical framework can be used to describe the exact frequency structure of non-Fourier motion and bridges the gap between such visual phenomena and their understanding in the frequency domain     

On the Fourier Properties of Discontinuous Motion

Retinal image motion and optical flow as its approximation are fundamental concepts in the field of vision, perceptual and computational. However, the computation of optical flow remains a challenging problem as image motion includes discontinuities and multiple values mostly due to scene geometry, surface translucency and various photometric effects such as reflectance. In this contribution, we analyze image motion in the frequency space with respect to motion discontinuities and translucence. We derive the frequency structure of motion discontinuities due to occlusion and we demonstrate its various geometrical properties. The aperture problem is investigated and we show that the information content of an occlusion almost always disambiguates the velocity of an occluding signal suffering from the aperture problem. In addition, the theoretical framework can describe the exact frequency structure of Non-Fourier motion and bridges the gap between Non-Fourier visual phenomena and their understanding in the frequency domain.     

Nutrient digestibility in food waste ingredients for Pekin and Muscovy ducks

Food wastes are valuable resources to be recycled into new added-value products through animal production. The determination of energy and digestibility values of these wastes is essential for feed formulation. Corn, soybean meal (SBM), and a total of nine industrial food waste ingredients were tested in a comparative metabolic study in Pekin and Muscovy ducklings at two different ages during growth. The "precision-feeding" technique was employed to establish DM, fat, and fiber digestibility as well as retention of N and energy (AME, AMEn in Pekins; and AME, AMEn, TME, TMEn in Muscovies) for the 11 ingredients. For Pekin at 3 wk of age, the AMEn of peanuts, tofu, pogo, granola, waste diet, bread, corn, SBM, okara, and brewers grains were 5,141, 4,019, 3,971, 3,908, 3,141, 2,279, 1,572, and 1,442 kcal/kg, respectively. For Pekin at 6 wk of age, the AMEn of peanuts, pogo, tofu, granola, waste diet, bread, corn, SBM, and okara were 5,340, 4,327, 4,254, 4,079, 3,567, 3,302, 3,201, 2,416, and 1,562 kcal/kg, respectively. For Muscovy at 7 wk of age, the TMEn of peanuts, pogo, granola, waste diet, corn, tofu, bread, SBM, okara, and peanut skin were 5,207, 4,321, 4,057, 3,733, 3,233, 3,180, 3,084, 2,236, 1,575, and 904 kcal/kg, respectively. For Muscovy at 11 wk of age, the TMEn of peanuts, pogo, granola, tofu, waste diet, corn, bread, SBM, okara, and brewers grains were 5,077, 4,137, 4,025, 3,921, 3,586, 3,254, 3,123, 2,245, 2,007, and 1,392 kcal/kg, respectively. Nitrogen retention was significantly (P < 0.05) higher for SBM, tofu, okara, pogo, peanuts, and the food waste diet and lower for bread, corn, granola, brewers grains, and peanut skin. Dry matter digestibility was high for granola, pogo, corn, bread, and the food waste diet. Fat digestibility was generally the same for all the ingredients and was consistently over 97%. Bread neutral detergent fiber (NDF) was significantly (P < 0.05) the most digestible (88.92% NDF digestibility), as it consisted of 96.29% hemicellulose, whereas okara NDF was significantly (P < 0.05) the least digestible (26.94% NDF digestibility) and contained only 14.38% hemicellulose. Peanut skins and SBM with 30% hemicellulose showed only slightly higher digestibilities of NDF. The results of this study establish reliable data for formulation of duck diets using the tested industrial food waste ingredients as well as corn and SBM in both Pekin and Muscovy ducklings at two different ages during growth to market weight.     

Grounding and ground fault protection of multiple generator installations on medium-voltage industrial and commercial power systems - Part 3: Protection Methods Working Group Report

This paper discusses typical grounding practices and ground fault protection methods for medium-voltage generator stators, highlighting their merits and drawbacks. Particular attention is given to applications of multiple generators connected to a single bus. The paper also provides an overview of the generator damage mechanism during stator ground faults. Problem areas associated with each type of grounding are identified and solutions are discussed. The paper also provides a list of references on the topic. The paper is intended as a guide to aid engineers in selecting adequate grounding and ground fault protection schemes for medium-voltage industrial and commercial generators for new installations, for evaluating existing systems, and for future expansion of facilities, to minimize generator damage from stator ground faults. These topics are presented in four separate parts, Parts 1-4. Part 1 covers scope, introduction, user examples of stator ground failure, and theoretical basis for the problem. Part 2 discusses various grounding methods used in industrial applications. Part 3 describes protection methods for the various types of grounding and Part 4 provides a conclusion and bibliography of additional resource material.     

A branch and bound algorithm for numerical Max-CSP

The Constraint Satisfaction Problem (CSP) framework allows users to define problems in a declarative way, quite independently from the solving process. However, when the problem is over-constrained, the answer “no solution” is generally unsatisfactory. A Max-CSP \(\mathcal{P}_m = \langle V, \textbf{D}, C \rangle\) is a triple defining a constraint problem whose solutions maximize the number of satisfied constraints. In this paper, we focus on numerical CSPs, which are defined on real variables represented as floating point intervals and which constraints are numerical relations defined in intension. Solving such a problem (i.e., exactly characterizing its solution set) is generally undecidable and thus consists in providing approximations. We propose a Branch and Bound algorithm that provides under and over approximations of a solution set that maximize the maximum number \({m_{\mathcal P}}\) of satisfied constraints. The technique is applied on three numeric applications and provides promising results.