35 research outputs found

    Environmental impact assessments of the Three Gorges Project in China: issues and interventions

    Get PDF
    The paper takes China's authoritative Environmental Impact Statement for the Yangzi (Yangtze) Three Gorges Project (TGP) in 1992 as a benchmark against which to evaluate emerging major environmental outcomes since the initial impoundment of the Three Gorges reservoir in 2003. The paper particularly examines five crucial environmental aspects and associated causal factors. The five domains include human resettlement and the carrying capacity of local environments (especially land), water quality, reservoir sedimentation and downstream riverbed erosion, soil erosion, and seismic activity and geological hazards. Lessons from the environmental impact assessments of the TGP are: (1) hydro project planning needs to take place at a broader scale, and a strategic environmental assessment at a broader scale is necessary in advance of individual environmental impact assessments; (2) national policy and planning adjustments need to react quickly to the impact changes of large projects; (3) long-term environmental monitoring systems and joint operations with other large projects in the upstream areas of a river basin should be established, and the cross-impacts of climate change on projects and possible impacts of projects on regional or local climate considered. © 2013 Elsevier B.V.Xibao Xu, Yan Tan, Guishan Yan

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

    Get PDF
    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

    Wearable activity trackers for promoting physical activity : a systematic meta-analytic review

    No full text
    Purpose: Although wearable activity trackers hold a promise of nudging people toward a more active lifestyle, current research reveals inconsistent findings regarding their effectiveness. The objectives of this paper are two-fold: (1) to synthesize evidence on the effects of wearable activity trackers for improving physical activities, and (2) to identify potential moderators of effect size. Methods: A systematic meta-analytic review was conducted. Forty-eight eligible papers based on forty-four distinct trials were identified through a systematic literature search process. Two authors independently extracted information from each study based on predefined data fields. Random-effects meta-analysis, subgroup analysis, and meta-regression analysis were employed. Results: First, interventions with wearable activity trackers significantly increased daily steps and weekly moderate-to-vigorous physical activity but had no impact on light physical activity or sedentary behavior. Second, daily steps and weekly moderate-to-vigorous physical activity were associated with participants’ characteristics (i.e., gender, age, medical condition, and baseline physical activity level) and intervention features (i.e., sensors, modes of expert support, and intervention duration). The identified factors explained 53% of the total variance for weekly moderate-to-vigorous physical activity. Conclusions: The use of wearable activity trackers effectively improves conscious exercise behavior, including daily steps and weekly moderate-to-vigorous physical activity, but not effective for modifying habitual behavior, such as light physical activity and sedentary behavior. We also explicitly show that the extent to which the interventions with wearable activity trackers help users is contingent on the type of users and the design and delivery of interventions. Future studies are called to validate the findings and to offer theoretical explanations.Accepted versionThis work is partly supported by the China Scholarship Council (CSC No.: 201906170120)

    Torrefaction of sawdust in a fluidized bed reactor

    No full text
    In the present work, stable fluidization of sawdust was achieved in a bench fluidized bed with an inclined orifice distributor without inert bed materials. A solids circulation pattern was established in the bed without the presence of slugging and channeling. The effects of treatment severity and weight loss on the solid product properties were identified. The decomposition of hemicelluloses was found to be responsible for the significant changes of chemical, physical and mechanical properties of the torrefied sawdust, including energy content, particle size distribution and moisture absorption capacity. The hydrophobicity of the torrefied sawdust was improved over the raw sawdust with a reduction of around 40 wt.% in saturated water uptake rate, and enhanced with increasing the treatment severity due to the decomposition of hemicelluloses which are rich in hydroxyl groups. The results in this study provided the basis for torrefaction in fluidized bed reactors. (C) 2011 Elsevier Ltd. All rights reserved

    Pelletization of torrefied sawdust and properties of torrefied pellets

    No full text
    Pelletization of torrefied sawdust from a fluidized bed reactor was investigated to quantify the energy consumption and pellet properties, including moisture adsorption, pellet density and Meyer hardness. Energy consumptions in compaction and extrusion for torrefied sawdust were significantly higher than those for untreated sawdust at the same compression temperature, while the moisture uptake rate of pellets decreased with increasing the severity of torrefaction. The densities of torrefied pellets were lower than the control pellet due to the loss of chemically bonded water and low-melting point compounds during torrefaction which act as a binding agent when softened at similar to 100 degrees C. The properties of pellets were affected by the removal of most low-melting or - softening point components. (C) 2012 Elsevier Ltd. All rights reserved

    Apple grading method based on neural network with ordered partitions and evidential ensemble learning

    No full text
    In order to improve the performance of the automatic apple grading and sorting system, in this paper, an ensemble model of ordinal classification based on neural network with ordered partitions and Dempster–Shafer theory is proposed. As a non-destructive grading method, apples are graded into three grades based on the Soluble Solids Content value, with features extracted from the preprocessed near-infrared spectrum of apple serving as model inputs. Considering the uncertainty in grading labels, mass generation approach and evidential encoding scheme for ordinal label are proposed, with uncertainty handled within the framework of Dempster–Shafer theory. Constructing neural network with ordered partitions as the base learner, the learning procedure of the Bagging-based ensemble model is detailed. Experiments on Yantai Red Fuji apples demonstrate the satisfactory grading performances of proposed evidential ensemble model for ordinal classification. © 2022 The Authors. CAAI Transactions on Intelligence Technology published by John Wiley &amp; Sons Ltd on behalf of The Institution of Engineering and Technology and Chongqing University of Technology.open access</p

    AN INVESTIGATION OF LUBRICATION CHARACTERISTICS AND PARAMETERS INFLUENCE ON MAIN BEARING IN HORIZONTAL DIESEL ENGINE

    No full text
    Based on the horizontal two-cylinder diesel engine,the main bearing elastohydrodynamic lubrication model was constructed in AVL EXCITE PU software,some results were acquired at the maximum torque working condition( 1600 r / min)under the consideration of the roughness of bearing bush and journal. The results showed that three main bearings’ minimum film thickness and maximum film pressure satisfy the design criterion. The 2nd main bearing ’s maximum film pressure is about150 MPa which is the oil pressure limits. The 2nd main bearing orbit was obvious centripetal movement,which showed that the2 nd main bearing had obvious bending moment. The bending moment was considered to analysis object,and the parameters influence to bending moment is width of main bearing,bearing clearance,oil groove width and oil port position with the orthogonal experimental design
    corecore