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Influence on Type of Cement on the SCC Formwork Pressure during and after Casting
Formworks for SCC are usually designed under the assumption of full hydrostatic pressure. Nevertheless, current research is attempting to explain the mechanism of this phenomenon as observed pressure usually is at the lower lever than expected. This causes formworks for SCC are usually overdesigned. It was noticed the rheological properties of fresh concrete might be a key to predict the SCC formwork pressure. Therefore, knowing the influence of fresh concrete properties on formwork pressure will enable to design formworks more efficiently. This paper presents the influence of type of cement on formwork pressure caused by SCC. Mixes were design under the assumption of equal dispersion ratio. Three types
of cement were investigated: portland, blast furnace and composite cement with a different w/c ratio (0.30, 0.40) and in presence of carboxyl ethers superplasticizer. Formwork pressure was determined on the element imitating a column with dimensions of 0.20x0.20m and a height of 1.20 m with casting speed of 7 m/h. Results show the formwork pressure was registered at the lower than hydrostatic level. Rheological properties had an influence on formwork pressure. It was noticed the different cement types had an influence on rheological properties. Lateral
pressure reduction over time was observed with the intensity depending on the cement.This paper was elaborated with the financial support of the Project No. 842/B/T02/2011/40 "The influence of time and technological factors on rheological properties of self-compacting concrete in terms of the pressure on the formwork" financed by the from the National Science Centre in Cracow, Poland, project “Innovative cementitious materials and concretes made with high – calcium fly ashes” co-financed by the EU from the European Regional Development Fund and the project "DoktoRIS -
Scholarship program for innovative Silesia" co-financed by the European Union under the European Social Fund. Research has been done in collaboration with HARSCO Infrastructure Poland HUNNEBECK Poland). This work was developed while Michał Drewniok was at Silesian University
of Technology, Faculty of Civil Engineering, Poland
Comparative Analysis of Energy Efficiency in Wheat Production in Different Climate Conditions of Europe
This paper presents results concerning energy efficiency of wheat production considered in the context of specific energy
input variation in different climatic conditions of Europe as well as case studies on implementation of selected energy saving
measures in practice. The source data collected from the six european union (EU) countries represent five agricultural regions of
continental Europe and three climates: continental, temperate and Mediterranean. The life cycle assessment (LCA) methodology was
applied to analyze the data excluding of pre-farm gate activities. The total primary energy consumption was decomposed into main
energy input streams and it was regressed to yield. In order to compare energy efficiency of wheat production across the geographical
areas, the data envelopment analysis (DEA) was applied. It was shown that the highest wheat yield (6.7 t/ha to 8.7 t/ha) at the lowest
specific energy input (2.08 GJ/t to 2.56 GJ/t) is unique for temperate climate conditions. The yield in continental and Mediterranean
climatic conditions is on average lower by 1.3 t/ha and 2.7 t/ha and energy efficiency lower by 14% and 38%, respectively. The case
studies have shown that the energy saving activities in wheat production may be universal for the climatic zones or specific for a
given geographical location. It was stated that trade-offs between energy, economic, and environmental effects, which are associated
with implementation of a given energy saving measure or a set of measures to a great extent depend on the current energy efficiency
status of the farm and opportunity for investment, which varies substantially across Europe
Text messaging and brief phone calls for weight loss in overweight and obese English- and Spanish-speaking adults: A 1-year, parallel-group, randomized controlled trial.
BACKGROUND:Weight loss interventions based solely on text messaging (short message service [SMS]) have been shown to be modestly effective for short periods of time and in some populations, but limited evidence is available for positive longer-term outcomes and for efficacy in Hispanic populations. Also, little is known about the comparative efficacy of weight loss interventions that use SMS coupled with brief, technology-mediated contact with health coaches, an important issue when considering the scalability and cost of interventions. We examined the efficacy of a 1-year intervention designed to reduce weight among overweight and obese English- and Spanish-speaking adults via SMS alone (ConTxt) or in combination with brief, monthly health-coaching calls. ConTxt offered 2-4 SMS/day that were personalized, tailored, and interactive. Content was theory- and evidence-based and focused on reducing energy intake and increasing energy expenditure. Monthly health-coaching calls (5-10 minutes' duration) focused on goal-setting, identifying barriers to achieving goals, and self-monitoring. METHODS AND FINDINGS:English- and Spanish-speaking adults were recruited from October 2011 to March 2013. A total of 298 overweight (body mass index [BMI] 27.0 to 39.9 kg/m2) adults (aged 21-60 years; 77% female; 41% Hispanic; 21% primarily Spanish speaking; 44% college graduates or higher; 22% unemployed) were randomly assigned (1:1) to receive either ConTxt only (n = 101), ConTxt plus health-coaching calls (n = 96), or standard print materials on weight reduction (control group, n = 101). We used computer-based permuted-block randomization with block sizes of three or six, stratified by sex and Spanish-speaking status. Participants, study staff, and investigators were masked until the intervention was assigned. The primary outcome was objectively measured percent of weight loss from baseline at 12 months. Differences between groups were evaluated using linear mixed-effects regression within an intention-to-treat framework. A total of 261 (87.2%) and 253 (84.9%) participants completed 6- and 12-month visits, respectively. Loss to follow-up did not differ by study group. Mean (95% confidence intervals [CIs]) percent weight loss at 12 months was -0.61 (-1.99 to 0.77) in the control group, -1.68 (-3.08 to -0.27) in ConTxt only, and -3.63 (-5.05 to -2.81) in ConTxt plus health-coaching calls. At 12 months, mean (95% CI) percent weight loss, adjusted for baseline BMI, was significantly different between ConTxt plus health-coaching calls and the control group (-3.0 [-4.99 to -1.04], p = 0.003) but not between the ConTxt-only and the control group (-1.07 [-3.05 to 0.92], p = 0.291). Differences between ConTxt plus health-coaching calls and ConTxt only were not significant (-1.95 [-3.96 to 0.06], p = 0.057). These findings were consistent across other weight-related secondary outcomes, including changes in absolute weight, BMI, and percent body fat at 12 months. Exploratory subgroup analyses suggested that Spanish speakers responded more favorably to ConTxt plus health-coaching calls than English speakers (Spanish contrast: -7.90 [-11.94 to -3.86], p < 0.001; English contrast: -1.82 [-4.03 to 0.39], p = 0.107). Limitations include the unblinded delivery of the intervention and recruitment of a predominantly female sample from a single site. CONCLUSIONS:A 1-year intervention that delivered theory- and evidence-based weight loss content via daily personalized, tailored, and interactive SMS was most effective when combined with brief, monthly phone calls. TRIAL REGISTRATION:ClinicalTrials.gov NCT01171586
Priorities for energy efficiency measures in agriculture.
This report provides a compilation of energy efficiency measures in agriculture, their
opportunities and constraints to implement energy efficient agricultural systems across
Europe as a result of the AGREE (Agriculture & Energy Efficiency) Coordination and Support
Action funded by the 7th research framework of the EU (www.agree.aua.gr). The report
dwells on earlier reports of the consortium, which listed potential energy efficiency
measures (Project Deliverable 2.3: Energy Saving Measures in Agriculture – Overview on the Basis of National Reports) and identified trade-offs and win-win situations of various energy efficiency measures in agriculture (Project Deliverable 3.1: Economic and environmental
analysis of energy efficiency measures in agriculture). It shows research gaps in crop
production, greenhouse production, animal husbandry and system approaches, which can
be regarded as priorities for energy efficiency measures in agriculture. The report is na important input for the strategic research agenda, which is one of the main outputs of the AGREE project
Economic and environmental analysis of energy efficiency measures in agriculture. Case Studies and trade offs.
This report is the result of the collaboration of the partners of the AGREE work-package “Economic and environmental analysis”, which is based on case study analyses of the partners in seven countries of the EU. The case studies show economic and environmental trade-offs in the different regions in the EU, for which each partner is responsible. Nevertheless prior to the reporting of the case studies an intensive discussion on a common methodological approach has been accomplished and applied to the case studies. The case studies show a wide range of different perspectives of energy efficiency in agriculture, but they are all based on the common methodology presented in Chapter 3. In Chapter 4, the case studies are presented, with authors indicated at the beginning of each section. Each section of Chapter 4 ends with a synthesis analysis of the results from the different case studies. Chapter 5 summarizes and concludes the report by highlighting the major findings of the analyses.
The report builds upon the “State of the Art in Energy Efficiency in Europe” published separately by the AGREE consortium (Gołaszewski et al. 2012), which shows the status quo of energy use and possible energy efficiency measures in agriculture across different production systems and regions in Europe. This report presents an economic and environmental analysis based on in-depth case studies which show the potential for, and constraints on, energy efficiency measures in agriculture with respect to the specific environments in Europe
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