3,387 research outputs found

    Mapping General System Characteristics to Non- Functional Requirements

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    The Function point analysis (FPA) method is the preferred scheme of estimation for project managers to determine the size, effort, schedule, resource loading and other such parameters. The FPA method by International Function Point Users Group (IFPUG) has captured the critical implementation features of an application through fourteen general system characteristics. However, Non- functional requirements (NFRs) such as functionality, reliability, efficiency, usability, maintainability, portability, etc. have not been included in the FPA estimation method. This paper discusses some of the NFRs and tries to determine a degree of influence for each of them. An attempt to factor the NFRs into estimation has been made. This approach needs to be validated with data collection and analysis.Comment: 5 page

    Quantifying the non-Gaussianity in the EoR 21-cm signal through bispectrum

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    The epoch of reionization (EoR) 21-cm signal is expected to be highly non-Gaussian in nature and this non-Gaussianity is also expected to evolve with the progressing state of reionization. Therefore the signal will be correlated between different Fourier modes (kk). The power spectrum will not be able capture this correlation in the signal. We use a higher-order estimator -- the bispectrum -- to quantify this evolving non-Gaussianity. We study the bispectrum using an ensemble of simulated 21-cm signal and with a large variety of kk triangles. We observe two competing sources driving the non-Gaussianity in the signal: fluctuations in the neutral fraction (xHIx_{\rm HI}) field and fluctuations in the matter density field. We find that the non-Gaussian contribution from these two sources vary, depending on the stage of reionization and on which kk modes are being studied. We show that the sign of the bispectrum works as a unique marker to identify which among these two components is driving the non-Gaussianity. We propose that the sign change in the bispectrum, when plotted as a function of triangle configuration cosθ\cos{\theta} and at a certain stage of the EoR can be used as a confirmative test for the detection of the 21-cm signal. We also propose a new consolidated way to visualize the signal evolution (with evolving xHI\overline{x}_{\rm HI} or redshift), through the trajectories of the signal in a power spectrum and equilateral bispectrum i.e. P(k)B(k,k,k)P(k)-B(k, k, k) space.Comment: 18 pages, 11 figures. Accepted for publication in MNRAS. Replaced to match the accepted versio

    The CMBR ISW and HI 21-cm Cross-correlation Angular Power Spectrum

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    The late-time growth of large scale structures (LSS) is imprinted in the CMBR anisotropy through the Integrated Sachs Wolfe (ISW) effect. This is perceived to be a very important observational probe of dark energy. Future observations of redshifted 21-cm radiation from the cosmological neutral hydrogen (HI) distribution hold the potential of probing the LSS over a large redshift range. We have investigated the possibility of detecting the ISW through cross-correlations between the CMBR anisotropies and redshifted 21-cm observations. Assuming that the HI traces the dark matter, we find that the ISW-HI cross-correlation angular power spectrum at an angular multipole l is proportional to the dark matter power spectrum evaluated at the comoving wave number l/r, where r is the comoving distance to the redshift from which the HI signal originated. The amplitude of the cross-correlation signal depends on parameters related to the HI distribution and the growth of cosmological perturbations. However the cross-correlation is extremely weak as compared to the CMBR anisotropies and the predicted HI signal. As a consequence the cross-correlation signal is smaller than the cosmic variance, and a statistically significant detection is not very likely.Comment: 13 pages, 4 eps figures, submitte

    Study of the de Almeida-Thouless (AT) line in the one-dimensional diluted power-law XY spin glass

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    We study the AT line in the one-dimensional power-law diluted XY spin glass model, in which the probability that two spins separated by a distance rr interact with each other, decays as 1/r2σ1/r^{2\sigma}. We develop a heat bath algorithm to equilibrate XY spins; using this in conjunction with the standard parallel tempering and overrelaxation sweeps, we carry out large scale Monte Carlo simulations. For σ=0.6\sigma=0.6 which is in the mean-field regime, we find clear evidence for an AT line. For σ=0.75\sigma = 0.75, there is evidence from finite size scaling studies for an AT transition but for σ=0.85\sigma = 0.85, the evidence for a transition is non-existent. We have also studied these systems at fixed temperature varying the field and discovered that at both σ=0.75\sigma = 0.75 and at σ=0.85\sigma =0.85 there is evidence of an AT transition! Confusingly, the correlation length and spin glass susceptibility as a function of the field are both entirely consistent with the predictions of the droplet picture and hence the non-existence of an AT line. The evidence from our simulations points to the complete absence of the AT line in dimensions outside the mean-field region and to the correctness of the droplet picture. Previous simulations which suggested there was an AT line can be attributed to the consequences of studying systems which are just too small. The collapse of our data to the droplet scaling form is poor for σ=0.75\sigma = 0.75 and to some extent also for σ=0.85\sigma = 0.85, when the correlation length becomes of the order of the length of the system, due to the existence of excitations which only cost a free energy of O(1)O(1), just as envisaged in the TNT picture of the ordered state of spin glasses. However, for the case of σ=0.85\sigma = 0.85 we can provide evidence that for larger system sizes, droplet scaling will prevail even when the correlation length is comparable to the system size.Comment: 23 pages, 15 figure

    Awareness of nursing students towards cancer and their comparison with medical students

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    Background: Cancer is the 2nd leading cause of mortality worldwide. The three leading cancers in India are cervical cancer, breast cancer and upper aerodigestive tract carcinoma. Cervical carcinoma is the 2nd most common cancer in women next to breast carcinoma. This study has been done to assess the knowledge, causation and preventive methods about the common cancers in India amongst Medical and Nursing students in a tertiary care center in rural Kerala. Preventive measures and early diagnosis of cancer can lead to decrease in mortality and morbidity. This can be achieved by creating awareness. A special emphasis has been made regarding cervical cancer and HPV vaccination in this study.Methods: A total of 337 medical and 148 nursing students from 1st year to final year were included in this study and the results were analysed by descriptive statistics.Results: Out of 337 medical and 148 nursing students, there was significant difference in knowledge between pretest/posttest and amongst the medical/nursing students. Medical students were found be more aware about the cancer, their causation and preventive methods as compared to the nursing students. 76.4% of nursing students were aware about the role of HPV (Human Papilloma Virus) in the causation of cervical cancer pretest. 98.6% of nursing students were aware about the role of HPV in causation of cervical cancer posttest following a short lecture. Following a short lecture both medical and nursing students were found to have more awareness.Conclusions: Creating awareness to the medical and nursing students who are intouch with the community and the patients is essential. Targeted health education in very important in creating a great impact about the knowledge of cancer in the community, thereby leading to decrease in mortality and morbidity
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