Human Jury Assessment of Image Quality as a Measurement: Modeling with Bayes Network

Image quality assessment has been done previously manually by human jury assessment as reference. Due to lack of rationality in human jury voting and its high costs it is desirable to replace it with instrumental measurements that can predict jury assessment reliably. But high uncertainty in jury assessments and sensitivity of image context make it cumbersome for the instrumental measurements. Previous research has shown that modeling with a Bayesian network can resolve some of the problems. A Bayesian network is a belief network of causal model representation of multivariate probabilistic distributions that describes the relationships between the interacting nodes in the form of conditional independency. By conditioning and marginalization operations we can estimate the conditional probabilities of unmeasured elements and their uncertainty in Bayes network. In this thesis we have considered a four-layer pre-existing Bayes network consisting of both qualitative and quantitative component and we have tried to assess probabilities of quality elements assessed by jurors based on instrumental measurement values. To analyze and to quantify the relationship between perceptual quality elements and instrumental measurements, we have calculated mutual information from our provided data set. Based on mutual information calculation and Kullback-Leibler distance measure we have investigated the sensitivity of the network, and we have tried to validate a feasible network model where network parameters have been selected such a way that it minimizes the uncertainties of our chosen Bayes network

Morphological and Histological Observation of Embryogenic Calli Derived from Immature Embryo of BRRI Dhan28 (Oryza sativa L.) Variety

Somatic embryogenesis is the most common method for regeneration in rice. In vitrostudies of indica rice (Oryza sativa L.) variety BRRI dhan28 was used for obtainingembryogenic calli from immature embryo culture on Murashige & Skoog mediumsupplemented with 2.5 mg/l dichlorophenoxyacetic acid (2,4-D) and 0.5 mg/lnaphthaleneacetic acid (NAA) showed the highest percentage (91%) of callus induction. Inthis combination 80% embryogenic calli were formed uneven with a crisp texture, loosestructure and salient multicellular structures on the surface while non embryogenic calliwere compact with a smooth surface. Under microscopic observation, embryogenic cells weresmaller, globular and abundant in cytoplasm with one or two big nuclei. Non embryogeniccells were little cytoplasm and few large vacuoles with no or only a small nucleus and wideintercellular spaces. Non embryogenic cells had a very low cell division capability whileembryogenic cells had a high capability for cell division and continued to divide andproduced somatic pro-embryos with a well–defined protodermis which could developfurther through the typical globular, heart, torpedo and cotyledonary stages. Only 80% ofembryogenic cells were induced high differentiation rate and developed 65 globular, 52heart-shape, 43 torpedo and 37 cotyledonary embryos of embryogenic cells after 30 to 45 daysof induction

Empirical analysis to the factors impact on succession process of the family-owned businesses in Bangladesh, moderating role of education

The purpose of this study is to examine the impact of the factors such as governance board, gender and business strategies on the succession planning in family-owned businesses (FOBs) in Bangladesh. Moreover, the study also examines the moderating role of education on the relationship between the governance board, gender and business strategies on the succession planning in FOBs in Bangladesh. Data obtained from 287 participants were analysed using PLS-SEM to test the hypotheses. The results show that the governance board has a significant impact on the succession process in FOBs in Bangladesh. However, this study finds no impact of gender and business strategies on the succession process in the family-owned businesses in Bangladesh. Moreover, education plays a moderating role only on the relationship between the governance board and succession process in FOBs. Implications of the findings including research limitations and future directions have been discussed

COMPARATIVE STUDY OF PROFESSIONALISM OF FUTURE MEDICAL PROFESSIONALS AMONG THREE PRIVATE MEDICAL COLLEGES OF BANGLADESH

Objectives: Medical professionalism forms the bridge between doctors and society. Conserving and maintaining professionalism is obligatory for physician curriculum. The objective of this study was to scrutinize and compare the professionalism of future medical professionals among different medical institutes. Methodology: It was a cross-sectional study conducted on 332 year-III and year-IV MBBS students of session 2012-2013 from three private medical colleges in Bangladesh. Data was collected using a mixed validated instrument containing items under fundamental elements of professionalism, measured by 5-points Likert scale giving a maximum score of 220. Results: Among 332 respondents, 44% were male, 56% female; Year-III respondents constituted 51% and Year-IV constituted 49%. Mean professionalism scores for male and female were 176.21 and 175.33, while for Year-III and Year-IV were 174.96 and 176.50 respectively. No significant differences observed between gender and year of study. However, significant differences were noticed between year-IV male students among three medical colleges. Majority (83%) students were imprecise of professionalism. Conclusions: Lack of focus is a worry for professionalism. Educators should focus on fundamental elements of professionalism. KEYWORDS: Professionalism, Medical-student, Core-values, Comparisons, Bangladesh

Shear behaviour of soft rock joints under constant normal stiffness

The shear behaviour of rock joints has been studied in the past, mainly using the conventional direct shear apparatus, where the normal load is kept constant during shearing. This is called the Constant Normal Load (CNL) condition. In this study, the shear behaviour of regular saw-tooth and natural unfilled soft joints was investigated in the laboratory under Constant Normal Stiffness (CNS) condition, using a large-scale shear apparatus. In CNS testing, the normal load varies during shear displacement of a non-planar joint, depending upon the extent of dilation and compression of the joint. Soft joints were prepared in the laboratory using ordinary casting plaster, whereas the natural joints were sampled from a rockslide in Kangaroo Valley, New South Wales. The Coordinate Measuring Machine (CMM) was used to map the joint surfaces precisely before and after the tests. Extensive tests were also conducted on idealised infilled joints under CNS for various infill thickness to asperity height (t/a) ratios. Commercial bentonite was used as the infill material in this study. A detailed literature review is presented in two separate chapters, one emphasising the shear behaviour of unfilled joints under CNS condition, and the other on the shear behaviour of infilled joints mainly under CNL. This was done to clearly distinguish the differences between CNS and CNL, and to emphasise the relevance of CNS in contrast to the conventional CNL approach. The effect of rate of shearing on the shear strength of soft joints having an asperity angle of 18.5° (Type II) was studied under CNS condition. Test results show that the rate of shearing has a considerable effect on the shear strength of joints. The peak shear stress of joints increases together with the dilation and normal stress as the shear rate is increased from 0.35 to 1.70 mm/min. A rate of shearing less than 0.50 mm/min has insignificant effect on the strength of joints under CNS. Test results obtained for natural (tension) joints, and joints having an asperity angle of 9.5 degrees (Type I) under CNS condition are compared with the conventional direct shear tests (Constant Normal Load). It is observed that the peak shear stress obtained under CNL condition is significantly lower than the CNS condition, especially for the natural (tension) joints. The normal stress increases with the shear displacement under the CNS condition whereas it remains unchanged for the CNL condition. The dilation of the joints under CNL condition is much greater in comparison with CNS testing. The strength envelope for CNL testing shows an upper bound for all the tests. Laboratory tests were also extended to include joints having asperity angles of 18.5 degrees (Type II), 26.5 degrees (type III) and natural (field) joints. Plots of shear stress against normal stress show that a non-linear (curved) strength envelope is acceptable for soft rock joints subjected to CNS conditions. The shear behaviour of soft joints (Type I and II) containing infill materials was investigated in the laboratory under CNS for a given range of initial normal stresses (σno) varying from 0.16 to 1.10 MPa. It was found that the shear strength of joints decreases considerably even with the addition of a thin layer of infill. Results also show that the effect of asperities on shear strength is significant up to a asperity height to infill thickness (t/a) ratio of 1.4-1.8, whereas the shear behaviour is controlled by the infill alone beyond this critical ratio. The shear displacement corresponding to the peak shear stress is considerably reduced once the infill starts to govern the shear behaviour of the joint. In this study, a new shear strength model for soft joints has been developed for the prediction of unfilled and infilled joint strength based on the Fourier transform method, energy balance principle and the hyperbolic stress-strain simulation. It is verified that the model predictions are in good agreement with the measured data. The applicability of the eNS technique in practice is discussed in detail with regards to the excavation of a mine roadway and in the case of slope instability in jointed media

Human Jury Assessment of Image Quality as a Measurement: Modeling with Bayes Network

Image quality assessment has been done previously manually by human jury assessment as reference. Due to lack of rationality in human jury voting and its high costs it is desirable to replace it with instrumental measurements that can predict jury assessment reliably. But high uncertainty in jury assessments and sensitivity of image context make it cumbersome for the instrumental measurements. Previous research has shown that modeling with a Bayesian network can resolve some of the problems. A Bayesian network is a belief network of causal model representation of multivariate probabilistic distributions that describes the relationships between the interacting nodes in the form of conditional independency. By conditioning and marginalization operations we can estimate the conditional probabilities of unmeasured elements and their uncertainty in Bayes network. In this thesis we have considered a four-layer pre-existing Bayes network consisting of both qualitative and quantitative component and we have tried to assess probabilities of quality elements assessed by jurors based on instrumental measurement values. To analyze and to quantify the relationship between perceptual quality elements and instrumental measurements, we have calculated mutual information from our provided data set. Based on mutual information calculation and Kullback-Leibler distance measure we have investigated the sensitivity of the network, and we have tried to validate a feasible network model where network parameters have been selected such a way that it minimizes the uncertainties of our chosen Bayes network

A new cluster analysis-marker-controlled watershed method for separating particles of granular soils

An accurate determination of particle-level fabric of granular soils from tomography data requires a maximum correct separation of particles. The popular marker-controlled watershed separation method is widely used to separate particles. However, the watershed method alone is not capable of producing the maximum separation of particles when subjected to boundary stresses leading to crushing of particles. In this paper, a new separation method, named as Monash Particle Separation Method (MPSM), has been introduced. The new method automatically determines the optimal contrast coefficient based on cluster evaluation framework to produce the maximum accurate separation outcomes. Finally, the particles which could not be separated by the optimal contrast coefficient were separated by integrating cuboid markers generated from the clustering by Gaussian mixture models into the routine watershed method. The MPSM was validated on a uniformly graded sand volume subjected to one-dimensional compression loading up to 32 MPa. It was demonstrated that the MPSM is capable of producing the best possible separation of particles required for the fabric analysis

X-ray Computed Tomography Imaging of the Microstructure of Sand Particles Subjected to High Pressure One-Dimensional Compression

This paper presents the results of X-ray CT imaging of the microstructure of sand particles subjected to high pressure one-dimensional compression leading to particle crushing. A high resolution X-ray CT machine capable of in situ imaging was employed to capture images of the whole volume of a sand sample subjected to compressive stresses up to 79.3 MPa. Images of the whole sample obtained at different load stages were analysed using a commercial image processing software (Avizo) to reveal various microstructural properties, such as pore and particle volume distributions, spatial distribution of void ratios, relative breakage, and anisotropy of particles