4,545 research outputs found
MODLEACH: A Variant of LEACH for WSNs
Wireless sensor networks are appearing as an emerging need for mankind.
Though, Such networks are still in research phase however, they have high
potential to be applied in almost every field of life. Lots of research is done
and a lot more is awaiting to be standardized. In this work, cluster based
routing in wireless sensor networks is studied precisely. Further, we modify
one of the most prominent wireless sensor network's routing protocol "LEACH" as
modified LEACH (MODLEACH) by introducing \emph{efficient cluster head
replacement scheme} and \emph{dual transmitting power levels}. Our modified
LEACH, in comparison with LEACH out performs it using metrics of cluster head
formation, through put and network life. Afterwards, hard and soft thresholds
are implemented on modified LEACH (MODLEACH) that boast the performance even
more. Finally a brief performance analysis of LEACH, Modified LEACH (MODLEACH),
MODLEACH with hard threshold (MODLEACHHT) and MODLEACH with soft threshold
(MODLEACHST) is undertaken considering metrics of throughput, network life and
cluster head replacements.Comment: IEEE 8th International Conference on Broadband and Wireless
Computing, Communication and Applications (BWCCA'13), Compiegne, Franc
Tuning the structural and dynamical properties of a dipolar Bose-Einstein condensate: Ripples and instability islands
It is now well established that the stability of aligned dipolar Bose gases
can be tuned by varying the aspect ratio of the external harmonic confinement.
This paper extends this idea and demonstrates that a Gaussian barrier along the
strong confinement direction can be employed to tune both the structural
properties and the dynamical stability of an oblate dipolar Bose gas aligned
along the strong confinement direction. In particular, our theoretical
mean-field analysis predicts the existence of instability islands immersed in
otherwise stable regions of the phase diagram. Dynamical studies indicate that
these instability islands, which can be probed experimentally with present-day
technology, are associated with the going soft of a Bogoliubov--de Gennes
excitation frequency with radial breathing mode character. Furthermore, we find
dynamically stable ground state densities with ripple-like oscillations along
the radial direction. These structured ground states exist in the vicinity of a
dynamical radial roton-like instability.Comment: 9 pages, 11 figure
Photoaversion in inherited retinal diseases: clinical phenotypes, biological basis, and qualitative and quantitative assessment
Severe light sensitivity is a feature common to a range of ophthalmological and neurological diseases. In
inherited retinal diseases (IRDs) particularly, this may be accompanied by significant visual disruption. These
symptoms are extremely debilitating for affected individuals and have significant implications in terms
of day-to-day activities. Underlying mechanisms remain to be fully elucidated. Currently, there are many
assessments of photoaversion (PA), however, all have limitations, with quantitative measurement in particular needing further evaluation. To understand the complexities associated with photoaversion from
different pathologies, qualitative and quantitative assessments of the light aversion response must be
standardized. There is no treatment to date, and strategies to alleviate symptoms focus on light avoidance.
With respect to IRDs, however, gene therapy is currently being investigated in clinical trials and promising
and further treatments may be on the horizon. The better characterization of these symptoms is an
important end point measure in IRD gene therapy trials
For profit and progress: Rethinking the role of the private sector in humanitarian action
Key global frameworks and guiding strategies including the Sendai Framework for Disaster Risk Reduction 2015-2030 highlight the value of the private sector in the fields of humanitarian action and disaster risk management (DRM). Nonetheless, the fundamental ‘business case’ for commercial enterprises to be actively engaged in DRM and addressing humanitarian crises still requires further examination and evidence-based consideration to determine mutually beneficial value addition. This paper provides a conceptual overview of the shift in the private sector’s engagement in humanitarian action and DRM. It also considers how such engagement with the private sector has corresponded with a heightened recognition for commercial enterprises to safeguard their own business operations from disaster events while implementing development interventions that address the needs of populations affected by disasters
The effect of distance on observed mortality, childhood pneumonia and vaccine efficacy in rural Gambia.
We investigated whether straight-line distance from residential compounds to healthcare facilities influenced mortality, the incidence of pneumonia and vaccine efficacy against pneumonia in rural Gambia. Clinical surveillance for pneumonia was conducted on 6938 children living in the catchment areas of the two largest healthcare facilities. Deaths were monitored by three-monthly home visits. Children living >5 km from the two largest healthcare facilities had a 2·78 [95% confidence interval (CI) 1·74-4·43] times higher risk of all-cause mortality compared to children living within 2 km of these facilities. The observed rate of clinical and radiological pneumonia was lower in children living >5 km from these facilities compared to those living within 2 km [rate ratios 0·65 (95% CI 0·57-0·73) and 0·74 (95% CI 0·55-0·98), respectively]. There was no association between distance and estimated pneumococcal vaccine efficacy. Geographical access to healthcare services is an important determinant of survival and pneumonia in children in rural Gambia
Permodelan Transport Kadmium (Cd) Dan Nikel (Ni) Dalam Lindi Menggunakan Software Pollute V7 (Studi Kasus: Tpa Sanggrahan, Temanggung)
Sanggrahan Landfill (Temanggung), completed with gravel, geotextile, geomembrane, and compacted clay. It's still has potential of contaminant mobilization through those liners that comes from solid waste in landfill. The purposes of this research for knowing the movement cadmium (Cd) and nickel(Ni) in leachate vertically in every depth. The contaminant movement from active zone head for control 1-well and from active zone head for control 2-well could be predicted by using model pollute v7 software. Pollute v7 is one dimension model, where needed the characteristic of the liners (depth, permeability, porosity, dry density, coef dispersion of hydrodinamics). This model describe the contaminant mobilization affected by dispersion, advection, diffusion, and retardation phenomenon. Based on 12 years forward model simulation in this study, the concentration of Cd and Ni will get increase. The results showed, value of cadmium concentration in control 1-well is 0,496 mg/l and in control 2-well is 0,4064 mg/l. Whereas, the value of nickel concentration in control 1-well is 0,382 mg/l and in control 2-well is 0,3665 mg/l. This prediction showed that Sanggrahan Landfill has potential in leachate mobilization. The study suggests that the application of geomembrane should has lower permeability than 0,5x10-12m/s for retarding contaminant transport
Gap Waveguide PMC Packaging for Improved Isolation of Circuit Components in High-Frequency Microwave Modules
In this paper, perfect magnetic conductor (PMC)-based packaging technique was used to improve the isolation performance among various microwave circuit components such as high-gain amplifier chains. In this approach, a periodic structure (such as metal pin rows) together with the ground plane of the substrate created a stopband for unwanted parallel plate or cavity modes as well as substrate modes, and thereby suppressed the problems of circuit resonances and related package phenomena. This paper describes two Ka-band amplifier chains that were tested with this new packaging technique. Firstly, a single amplifier chain was tested for maximum stable gain operation, and it was found that the stable gain of >65 dB was achieved, whereas traditional metal wall package with RF absorber offered stable gain of 40 dB, thus showing significant isolation improvement. Secondly, two high-gain amplifier chains were placed side by side and their mutual isolation was tested. With the proposed gap waveguide packaging, a minimum isolation of 78 dB was achieved, whereas a complete metal shield provided a minimum isolation of only 64 dB over the band of interest
The Experience of International Students and Institutional Recommendations: A Comparison Between the Students From the Developing and Developed Regions
Prior studies on the experiences of international students in China have mostly focused on their academic, sociocultural, and accommodation experiences. Hence, student health and safety, discrimination, and the services by the International Student Office (ISO) have remained unexplored. Moreover, due to the motivational differences between the students from developing and developed regions, a study that samples students from both regions may depict an exact picture of the experience of international students. Therefore, the objective of this study is to examine the influence of the dimensions (including those dimensions that have been ignored) of the experience of international students on their satisfaction. In addition, we make recommendations regarding Chinese institutes for future students based on a comparison between the students from developing and developed regions. Using hierarchical regression analysis, this study reveals that educational and non-educational experiences vary among students from different regions. Therefore, based on developing (e.g., Asia and Africa) and developed (e.g., America, Europe, and Australia) regions, important recommendations are discussed regarding how educational institutions and the Chinese government could best allocate resources and introduce policies to improve the experience of international students
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