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First CRDS-measurements of water vapour continuum in the 940nm absorption band
Measurements of near-infrared water vapour continuum using continuous wave cavity ring down spectroscopy (cw-
CRDS) have been performed at around 10611.6 and 10685:2 cm1. The continuum absorption coefficients for N2-
broadening have been determined for two temperatures and wavenumbers.
These results represent the first near-IR continuum laboratory data determined within the complex spectral environment in the 940nm water vapour band and are in reasonable agreement with simulations using the semiempirical CKD formulation
Reflector antennas with low sidelobes, low cross polarization, and high aperture efficiency
Techniques are presented for computing the horn near field patterns on the subreflectors and for correcting the phase center errors of the horn pattern by shaping the subreflector surface. The diffraction pattern computations for scanned beams are described. The effects of dish aperture diffraction on pattern bandwidth are investigated. A model antenna consisting of a reflector, shaped subreflector, and corrugated feed horn is described
Spring wheat yield assessment under drought conditions using vegetation health index: case of Canadian prairies
Non-Peer ReviewedAgricultural drought is a major climate concern which occurs frequently on Canadian prairies. It
acts negatively on crop production, which directly affects the Canadian economy. The
Normalized Difference Vegetation Index (NDVI) has been widely used to assess crop yield
losses related to drought events. However, this index suffers from some shortcomings such as the
apparent time lag between drought impact due to rainfall deficit and NDVI response. This study
was undertaken to investigate the effectiveness of the integrated Vegetation Health Index (iVHI)
for the assessment of spring wheat yield across Canadian prairies. A time series of five years
from the Advanced Very High Resolution Radiometer (AVHRR) sensor were used to develop a
spring wheat yield model for three agroclimatic regions: subarid, semiarid and subhumid. The
results demonstrated that spring wheat yield assessment is feasible through the use of iVHI,
especially in subarid and semiarid regions where it reached a correlation coefficient of 0.75 and
0.61, respectively. This finding shows that iVHI can be used to estimate spring wheat yield losses
due to agricultural drought across the Canadian prairies. However, in subhumid regions where
spring wheat growing conditions are favourable because of adequate water supply, the integrated
NDVI (iNDVI) outperforms iVHI with a correlation coefficient of 0.44 compared to 0.34.
Consequently, to develop an efficient tool, it suggested coupling the iVHI with iNDVI to better
estimate spring wheat yield in the Canadian prairies
Sclerostin does not play a major role in the pathogenesis of skeletal complications in type 2 diabetes mellitus
In contrast to previously reported elevations in serum sclerostin levels in diabetic patients, the present study shows that the impaired bone microarchitecture and cellular turnover associated with type 2 diabetes mellitus (T2DM)-like conditions in ZDF rats are not correlated with changes in serum and bone sclerostin expression. INTRODUCTION: T2DM is associated with impaired skeletal structure and a higher prevalence of bone fractures. Sclerostin, a negative regulator of bone formation, is elevated in serum of diabetic patients. We aimed to relate changes in bone architecture and cellular activities to sclerostin production in the Zucker diabetic fatty (ZDF) rat. METHODS: Bone density and architecture were measured by micro-CT and bone remodelling by histomorphometry in tibiae and femurs of 14-week-old male ZDF rats and lean Zucker controls (n = 6/group). RESULTS: ZDF rats showed lower trabecular bone mineral density and bone mass compared to controls, due to decreases in bone volume and thickness, along with impaired bone connectivity and cortical bone geometry. Bone remodelling was impaired in diabetic rats, demonstrated by decreased bone formation rate and increased percentage of tartrate-resistant acid phosphatase-positive osteoclastic surfaces. Serum sclerostin levels (ELISA) were higher in ZDF compared to lean rats at 9 weeks (+40 %, p < 0.01), but this difference disappeared as their glucose control deteriorated and by week 14, ZDF rats had lower sclerostin levels than control rats (-44 %, p < 0.0001). Bone sclerostin mRNA (qPCR) and protein (immunohistochemistry) were similar in ZDF, and lean rats at 14 weeks and genotype did not affect the number of empty osteocytic lacunae in cortical and trabecular bone. CONCLUSION: T2DM results in impaired skeletal architecture through altered remodelling pathways, but despite altered serum levels, it does not appear that sclerostin contributes to the deleterious effect of T2DM in rat bone
CONDA-PM -- A Systematic Review and Framework for Concept Drift Analysis in Process Mining
Business processes evolve over time to adapt to changing business
environments. This requires continuous monitoring of business processes to gain
insights into whether they conform to the intended design or deviate from it.
The situation when a business process changes while being analysed is denoted
as Concept Drift. Its analysis is concerned with studying how a business
process changes, in terms of detecting and localising changes and studying the
effects of the latter. Concept drift analysis is crucial to enable early
detection and management of changes, that is, whether to promote a change to
become part of an improved process, or to reject the change and make decisions
to mitigate its effects. Despite its importance, there exists no comprehensive
framework for analysing concept drift types, affected process perspectives, and
granularity levels of a business process. This article proposes the CONcept
Drift Analysis in Process Mining (CONDA-PM) framework describing phases and
requirements of a concept drift analysis approach. CONDA-PM was derived from a
Systematic Literature Review (SLR) of current approaches analysing concept
drift. We apply the CONDA-PM framework on current approaches to concept drift
analysis and evaluate their maturity. Applying CONDA-PM framework highlights
areas where research is needed to complement existing efforts.Comment: 45 pages, 11 tables, 13 figure
Generating business process recommendations with a population-based meta-heuristic
In order to provide both guidance and flexibility to users during process execution, recommendation systems have been proposed. Existing recommendation systems mainly focus on offering recommendation according to the process optimization goals (time, cost…). In this paper we offer a new approach that primarily focuses on maximizing the flexibility during execution. This means that by following the recommendations, the user retains maximal flexibility to divert from them later on. This makes it possible to handle (possibly unknown) emerging constraints during execution. The main contribution of this paper is an algorithm that uses a declarative process model to generate a set of imperative process models that can be used to generate recommendations
Investigating Differences between Graphical and Textual Declarative Process Models
Declarative approaches to business process modeling are regarded as well
suited for highly volatile environments, as they enable a high degree of
flexibility. However, problems in understanding declarative process models
often impede their adoption. Particularly, a study revealed that aspects that
are present in both imperative and declarative process modeling languages at a
graphical level-while having different semantics-cause considerable troubles.
In this work we investigate whether a notation that does not contain graphical
lookalikes, i.e., a textual notation, can help to avoid this problem. Even
though a textual representation does not suffer from lookalikes, in our
empirical study it performed worse in terms of error rate, duration and mental
effort, as the textual representation forces the reader to mentally merge the
textual information. Likewise, subjects themselves expressed that the graphical
representation is easier to understand
On decidability and complexity of low-dimensional robot games
A robot game, also known as a Z-VAS game, is a two-player vector addition game played on the integer lattice Zn, where one of the players, Adam, aims to avoid the origin while the other player, Eve, aims to reach the origin. The problem is to decide whether or not Eve has a winning strategy. In this paper we prove undecidability of the two-dimensional robot game closing the gap between undecidable and decidable cases. We also prove that deciding the winner in a robot game with states in dimension one is EXPSPACE-complete and study a subclass of robot games where deciding the winner is in EXPTIME
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