63 research outputs found
The NISPAcee journal of public administration and policy
This paper introduces a new approach for conducting project feasibility study by embracing the principles of sustainable development. Construction projects, in particular, infrastructures have major influence on the attainment of sustainable development, thus project sustainability needs to be considered. This becomes a pressing issue particularly in those developing countries or regions, such as China where a huge amount of construction works are currently performed and remain to happen in the future. Previous study has addressed little on the relevance of project feasibility study to project sustainability performance. The importance of incorporating sustainable development principles in conducting project feasibility study is not effectively understood by project stakeholders. This paper addresses major challenges of undertaking project feasibility study in line with sustainable construction practice with reference to the Chinese construction industry. A case study approach is the major research method in this study. The research team collected 87 feasibility study reports from various projects. Attributes are used for measuring project performance, including 18 economic performance attributes, nine social performance attributes, and eight environmental performance attributes. Research results show that economic performance is given the most concern in the current practice of project feasibility study, whilst less attention is given to the social and environmental performance. The study reveals the insufficiency of examining the performance of implementing a construction project from the perspective of sustainable development. The results also suggest the need for shifting the traditional approach of project feasibility study to a new approach that embraces the principles of sustainable development
Impacts of Drought on Maize and Soybean Production in Northeast China During the Past Five Decades.
Climate change has a distinct impact on agriculture in China, particularly in the northeast, a key agriculture area sensitive to extreme hydroclimate events. Using monthly climate and agriculture data, the influence of drought on maize and soybean yields-two of the main crops in the region-in northeast China since 1961 to 2017 were investigated. The results showed that the temperature in the growing season increased by 1.0 °C from the period 1998-2017 to the period 1961-1980, while the annual precipitation decreased slightly. However, precipitation trends varied throughout the growing season (May-September), increasing slightly in May and June, but decreasing in July, August and September, associated with the weakening of the East Asian summer monsoon. Consequently, the annual and growing season drought frequency increased by 15%, and 25%, respectively, in the period 1998-2017 relative to the period 1961-1980. The highest drought frequency (55%) was observed in September. At the same time, the drought intensity during the growing season increased by 7.8%. The increasing frequency and intensity of drought had negative influences on the two crops. During moderate drought years in the period 1961-2017, 3.2% and 10.4% of the provincial maize and soybean yields were lost, respectively. However, during more severe drought years, losses doubled for soybean (21.8%), but increased more than four-fold for maize (14.0%). Moreover, in comparison to the period 1961-1980, a higher proportion of the yields were lost in the period 1998-2017, particularly for maize, which increased by 15% (increase for soybean was 2.4%). This change largely depends on increasing droughts in August and September, when both crops are in their filling stages. The impact of drought on maize and soybean production was different during different growth stages, where a strong relationship was noted between drought and yield loss of soybean in its filling stage. Given the sensitivity of maize and soybean yields in northeast China to drought, and the observed production trends, climate change will likely have significant negative impacts on productivity in the future
Short and soft: multi-domain organization, tunable dynamics and jamming in suspensions of grafted colloidal cylinders with small aspect ratio
The yet virtually unexplored class of soft colloidal rods with small aspect
ratio is investigated and shown to exhibit a very rich phase and dynamic
behavior, spanning from liquid to nearly melt state. Instead of nematic order,
these short and soft nanocylinders alter their organization with increasing
concentration from isotropic liquid with random orientation to one with
preferred local orientation and eventually a multi-domain arrangement with
local orientational order. The latter gives rise to a kinetically suppressed
state akin to structural glass with detectable terminal relaxation, which, on
increasing concentration reveals features of hexagonally packed order as in
ordered block copolymers. The respective dynamic response comprises four
regimes, all above the overlapping concentration of 0.02 g/ml: I) from 0.03 to
0.1 g/mol the system undergoes a liquid-to-solid like transition with a
structural relaxation time that grows by four orders of magnitude. II) from 0.1
to 0.2 g/ml a dramatic slowing-down is observed and is accompanied by an
evolution from isotropic to multi-domain structure. III) between 0.2 and 0.6
g/mol the suspensions exhibit signatures of shell interpenetration and jamming,
with the colloidal plateau modulus depending linearly on concentration. IV) at
0.74 g/ml in the densely jammed state, the viscoelastic signature of
hexagonally packed cylinders from microphase-separated block copolymers is
detected. These properties set short and soft nanocylinders apart from long
colloidal rods (with large aspect ratio) and provide insights for fundamentally
understanding the physics in this intermediate soft colloidal regime, as well
as and for tailoring the flow properties of non-spherical soft colloids
Development and in vivo validation of tissue-engineered, small-diameter vascular grafts from decellularized aortae of fetal pigs and canine vascular endothelial cells
The Implications of Relationships between Human Diseases and Metabolic Subpathways
One of the challenging problems in the etiology of diseases is to explore the relationships between initiation and progression of diseases and abnormalities in local regions of metabolic pathways. To gain insight into such relationships, we applied the âk-cliqueâ subpathway identification method to all disease-related gene sets. For each disease, the disease risk regions of metabolic pathways were then identified and considered as subpathways associated with the disease. We finally built a disease-metabolic subpathway network (DMSPN). Through analyses based on network biology, we found that a few subpathways, such as that of cytochrome P450, were highly connected with many diseases, and most belonged to fundamental metabolisms, suggesting that abnormalities of fundamental metabolic processes tend to cause more types of diseases. According to the categories of diseases and subpathways, we tested the clustering phenomenon of diseases and metabolic subpathways in the DMSPN. The results showed that both disease nodes and subpathway nodes displayed slight clustering phenomenon. We also tested correlations between network topology and genes within disease-related metabolic subpathways, and found that within a disease-related subpathway in the DMSPN, the ratio of disease genes and the ratio of tissue-specific genes significantly increased as the number of diseases caused by the subpathway increased. Surprisingly, the ratio of essential genes significantly decreased and the ratio of housekeeping genes remained relatively unchanged. Furthermore, the coexpression levels between disease genes and other types of genes were calculated for each subpathway in the DMSPN. The results indicated that those genes intensely influenced by disease genes, including essential genes and tissue-specific genes, might be significantly associated with the disease diversity of subpathways, suggesting that different kinds of genes within a disease-related subpathway may play significantly differential roles on the diversity of diseases caused by the corresponding subpathway
Body mass index (BMI) may be a prognostic factor for gastric cancer with peritoneal dissemination
Optimized cross-layer forward error correction coding for H.264 AVC video transmission over wireless channels
Forward error correction (FEC) codes that can provide unequal error protection (UEP) have been used recently for video transmission over wireless channels. These video transmission schemes may also benefit from the use of FEC codes both at the application layer (AL) and the physical layer (PL). However, the interaction and optimal setup of UEP FEC codes at the AL and the PL have not been previously investigated. In this paper, we study the cross-layer design of FEC codes at both layers for H.264 video transmission over wireless channels. In our scheme, UEP Luby transform codes are employed at the AL and rate-compatible punctured convolutional codes at the PL. In the proposed scheme, video slices are first prioritized based on their contribution to video quality. Next, we investigate the four combinations of cross-layer FEC schemes at both layers and concurrently optimize their parameters to minimize the video distortion and maximize the peak signal-to-noise ratio. We evaluate the performance of these schemes on four test H.264 video streams and show the superiority of optimized cross-layer FEC design.Peer reviewedElectrical and Computer Engineerin
Development and validation of a prognostic risk score for major bleeding in patients undergoing percutaneous coronary intervention via the femoral approach.
AIMS: Major bleeding after percutaneous coronary intervention (PCI) is an independent risk factor for early and late mortality. We developed and validated a risk score predictive of major bleeding after PCI using the femoral approach. METHODS AND RESULTS: Baseline clinical and procedural variables from two contemporary, multicentre, randomized PCI trials were used for risk score development (the REPLACE-2 trial, n = 6002) and validation (the REPLACE-1 trial, n = 1056). On the basis of the odds ratio, independent risk factors were assigned a weighted integer, the sum of which comprised a total risk score. Seven variables were identified as independent correlates of major bleeding (age >55 years, female gender, estimated glomerular filtration rate <60 mL/min/1.73 m(2), pre-existing anaemia, administration of low-molecular-weight heparin within 48 h pre-PCI, use of glycoprotein IIb/IIIa inhibitors, and intraaortic balloon pump use). In the development set, the risk of major bleeding varied from 1.0% in patients without risk factors to 5.4% in high-risk patients. The discriminatory power of this risk model was confirmed in the validation data set (area under the receiver operating curve = 0.62). CONCLUSION: A simple risk score of baseline clinical and procedural variables is useful to predict the incidence of major peri-procedural bleeding after contemporary PCI using the femoral approach
An Introduction to Vein Presentation Attacks and Detection
The domain of presentation attacks (PA), including vulnerability studies and detection (PAD) remains very much unexplored by available scientific literature in biometric vein recognition. Contrary to other modalities that use visual spectral sensors for capturing biometric samples, vein biometrics is typically implemented with near-infrared imaging. The use of invisible light spectra challenges the cre- ation PA instruments, but does not render it impossible. In this chapter, we provide an overview of current landscape for PA manufacturing in possible attack vectors for vein recognition, describe existing public databases and baseline techniques to counter such attacks. The reader will also find material to reproduce experiments and findings for fingervein recognition systems. We provide this material with the hope it will be extended to other vein recognition systems and improved in time
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