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Experimental and theoretical research on the electrical conductivity of a liquid desiccant for the liquid desiccant air-conditioning system: LiCl aqueous solution
At present, the energy consumption in buildings occupies a large proportion of total energy use, and air-conditionings cost a large proportion of energy in the buildings. The liquid desiccant air-conditioning system has a good energy saving potential and the electrodialysis (ED) regeneration is a reliable choice for the liquid desiccant regeneration. In order to establish the energy consumption model and the performance coefficient model of liquid desiccant air-conditioning system based on ED regeneration using LiCl, experimental and theoretical research on the electrical conductivity of LiCl aqueous solution with a lot of concentrations and temperatures was conducted in this paper. The results show that when polynomial degrees of the mass concentration and the temperature of the LiCl aqueous solution are both 3, the electrical conductivity model for the LiCl aqueous solution is most suitable as its simplicity and high accuracy. Moreover, when the concentration is 36% and the temperature is 22 °C, the liquid desiccant cooling system has the maximum COP of about 5. Finally, a case study of a small office room was conducted, and the result shows that the liquid desiccant cooling system based on electrodialysis regeneration has a good energy-saving potential
Possibly New Charmed Baryon States from Decay
We examine the invariant mass spectrum of in decay measured by BABAR and find that through the 2-step processes of
, where denotes a
charmed baryon state, some of the peaks can be identified with the established
, and . Moreover, in
order to account for the measured spectrum, it is necessary to introduce a new
charmed baryon resonance with MeV.Comment: 8 pages, 1 figure, title changed and discussions updated, version
accepted for publication in Phys. Rev.
Learning Points and Routes to Recommend Trajectories
The problem of recommending tours to travellers is an important and broadly
studied area. Suggested solutions include various approaches of
points-of-interest (POI) recommendation and route planning. We consider the
task of recommending a sequence of POIs, that simultaneously uses information
about POIs and routes. Our approach unifies the treatment of various sources of
information by representing them as features in machine learning algorithms,
enabling us to learn from past behaviour. Information about POIs are used to
learn a POI ranking model that accounts for the start and end points of tours.
Data about previous trajectories are used for learning transition patterns
between POIs that enable us to recommend probable routes. In addition, a
probabilistic model is proposed to combine the results of POI ranking and the
POI to POI transitions. We propose a new F score on pairs of POIs that
capture the order of visits. Empirical results show that our approach improves
on recent methods, and demonstrate that combining points and routes enables
better trajectory recommendations
Bridgeness: A Local Index on Edge Significance in Maintaining Global Connectivity
Edges in a network can be divided into two kinds according to their different
roles: some enhance the locality like the ones inside a cluster while others
contribute to the global connectivity like the ones connecting two clusters. A
recent study by Onnela et al uncovered the weak ties effects in mobile
communication. In this article, we provide complementary results on document
networks, that is, the edges connecting less similar nodes in content are more
significant in maintaining the global connectivity. We propose an index named
bridgeness to quantify the edge significance in maintaining connectivity, which
only depends on local information of network topology. We compare the
bridgeness with content similarity and some other structural indices according
to an edge percolation process. Experimental results on document networks show
that the bridgeness outperforms content similarity in characterizing the edge
significance. Furthermore, extensive numerical results on disparate networks
indicate that the bridgeness is also better than some well-known indices on
edge significance, including the Jaccard coefficient, degree product and
betweenness centrality.Comment: 10 pages, 4 figures, 1 tabl
Fractional Quantum Hall Effect of Hard-Core Bosons in Topological Flat Bands
Recent proposals of topological flat band (TFB) models have provided a new
route to realize the fractional quantum Hall effect (FQHE) without Landau
levels. We study hard-core bosons with short-range interactions in two
representative TFB models, one of which is the well known Haldane model (but
with different parameters). We demonstrate that FQHE states emerge with
signatures of even number of quasi-degenerate ground states on a torus and a
robust spectrum gap separating these states from higher energy spectrum. We
also establish quantum phase diagrams for the filling factor 1/2 and illustrate
quantum phase transitions to other competing symmetry-breaking phases.Comment: 4 pages, 6 figure
Multiwavelength observations of a partially eruptive filament on 2011 September 8
In this paper, we report our multiwavelength observations of a partial
filament eruption event in NOAA active region 11283 on 2011 September 8. A
magnetic null point and the corresponding spine and separatrix surface are
found in the active region. Beneath the null point, a sheared arcade supports
the filament along the highly complex and fragmented polarity inversion line.
After being activated, the sigmoidal filament erupted and split into two parts.
The major part rose at the speeds of 90150 km s before reaching the
maximum apparent height of 115 Mm. Afterwards, it returned to the solar
surface in a bumpy way at the speeds of 2080 km s. The rising and
falling motions were clearly observed in the extreme-ultravoilet (EUV), UV, and
H wavelengths. The failed eruption of the main part was associated with
an M6.7 flare with a single hard X-ray source. The runaway part of the
filament, however, separated from and rotated around the major part for 1
turn at the eastern leg before escaping from the corona, probably along
large-scale open magnetic field lines. The ejection of the runaway part
resulted in a very faint coronal mass ejection (CME) that propagated at an
apparent speed of 214 km s in the outer corona. The filament eruption
also triggered transverse kink-mode oscillation of the adjacent coronal loops
in the same AR. The amplitude and period of the oscillation were 1.6 Mm and 225
s. Our results are important for understanding the mechanisms of partial
filament eruptions and provide new constraints to theoretical models. The
multiwavelength observations also shed light on space weather prediction.Comment: 46 pages, 17 figures, 1 table, accepted for publication in Ap
Suicide contagion: A systematic review of definitions and research utility
Objectives Despite the common use of contagion to analogize the spread of suicide, there is a lack of rigorous assessment of the underlying concept or theory supporting the use of this term. The present study aims to examine the varied definitions and potential utility of the term contagion in suicide-related research. Methods 100 initial records and 240 reference records in English were identified as relevant with our research objectives, through systematic literature screening. We then conducted narrative syntheses of various definitions and assessed their potential value for generating new research. Results 20.3% of the 340 records used contagion as equivalent to clustering (contagion-as-cluster); 68.5% used it to refer to various, often related mechanisms underlying the clustering phenomenon (contagion-as-mechanism); and 11.2% without clear definition. Under the category of contagion-as-mechanism, four mechanisms have been proposed to explain how suicide clusters occurred: transmission (contagion-as-transmission), imitation (contagion-as-imitation), contextual influence (contagion-as-context), and affiliation (contagion-as-affiliation). Contagion-as-cluster both confounds and constrains inquiry into suicide clustering by blending proposed mechanism with the phenomenon to be studied. Contagion-as-transmission is, in essence, a double or internally redundant metaphor. Contagion-as-affiliation and contagion-as-context involve mechanisms that are common mechanisms that often occur independently of apparent contagion, or may serve as a facilitating background. When used indiscriminately, these terms may create research blind spots. Contagion-as-imitation combines perspectives from psychology, sociology, and public health research and provides the greatest heuristic utility for examining whether and how suicide and suicidal behaviors may spread among persons at both individual and population levels. Conclusion Clarifying the concept of “suicide contagion” is an essential step for more thoroughly investigating its mechanisms. Developing a clearer understanding of the apparent spread of suicide-promoting influences can, in turn, offer insights necessary to build the scientific foundation for prevention and intervention strategies that can be applied at both individual and community levels.published_or_final_versio
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