Factors affecting the performance of family planning workers: importance of geographical information systems in empirical analysis

Substantial variation in contraceptive prevalence rates (CPRs) and fertility rates (FRs) between community health workers (CHWs) has been documented since the inception of the Matlab family planning program in rural Bangladesh. The coefficients of variation of these indicators for Matlab CHWs were 7% and 26%, respectively, in 1995. To identify the reasons for these performance variations, geographical information system (GIS) approaches were applied to longitudinal and cross-sectional data on 80 CHWs for the period 1980-95. Each observation in the data-set included catchment area-specific characteristics, measures of CHW efficiency in service delivery, and CHW-specific characteristics for one specific year. A one-unit increase in the average age of target women in the catchment area increases the CPR by 9.2%. The CPR increases by 0.2% for each 1% increase in women's literacy and decreases by 0.1% for each 1% increase in the number of Muslim households in the catchment area. An increase of 1 sq. km in the size of the catchment area reduces the CPR by 3%. CHW performance increases with age up to 45 years and then decreases. Similarly, a 1-year increase in the average age of target women reduces the FR by 2%. A 10% increase in the size of the catchment area reduces program performance by increasing the FR by 1.4%. A single geographic barrier to movement increases the FR by 1%. This analysis indicates that CHW performance can be improved significantly by defining catchment areas through use of GIS techniques. Without knowledge of the spatial distribution of population and the physical barriers to movement, allocating a fixed number of clients per CHW may not be the most efficient approach.     

Optimal estimation of ship's attitudes for beampattern corrections in a coaxial circular array

A study is conducted to estimate the accurate attitude of a ship's motion and the estimation is used to arrive at the corrections required for a farfield pattern of a coaxial circular array. The relevant analytical expression is developed for the computation of moving average filter weights to estimate the ship's attitude for beamsteerings at different sea conditions. Farfield patterns are presented for different steered directions for the coaxial circular array of the additive type, and the multiplicative array technique is also used for beamsteering for higher steering angles to observe its control on the sidelobes as well as for the main beamwidths. In order to introduce an adaptive filter to estimate the accurate attitude for stable sonar platform, an adaptive parameter is examined for bathymetric applications where nonstationary ship movement prevails.     

An Efficient Accurate Direct Solution of Poisson’s Equation for Computation of Meteorological Parameters

Poisson's equation is solved numerically by two direct methods, viz. Block Cyclic Reduction (BCR) method and Fourier Method. Qualitative and quantitative comparison between the numerical solutions obtained by two methods indicates that BCR method is superior to Fourier method in terms of speed and accuracy. Therefore. BCR method is applied to solve (?)2(?)= ζ and (?)2X= D from observed vorticity and divergent values. Thereafter the rotational and divergent components of the horizontal monsoon wind in the lower troposphere are reconstructed and are com pared with the results obtained by Successive Over-Relaxation (SOR) method as this indirect method is generally in more use for obtaining the streamfunction ((?)) and velocity potential (X) fields in NWP models. It is found that the results of BCR method are more reliable than SOR method.     

Frequency Distribution of Tropospheric Triad Energy Interactions During Summer Monsoon 1988

—In order to understand the physical mechanism for maintenance of low frequency waves, computations of nonlinear kinetic energy (KE) exchanges into individual triad interactions in frequency domain by use of cross-spectral technique over global tropics (20°S–30°N) at 850 hPa and 200 hPa for June, July and August of 1988 are carried out. The KE exchanges among different frequencies and the interactions between the transient eddies and the time mean flow are found to be an order of magnitude smaller in the lower troposphere than those in the upper troposphere. The results show two distinct spectral peaks of periods 45 and 25 days in nonlinear energy transfer in the lower troposphere. The former is more pronounced than the latter. The role of time mean flow on the low frequency transients is found to be secondary compared to the effect of the leading term due to nonlinear interactions in the lower troposphere. Low frequency waves suffer a net loss of energy in the upper troposphere. In the lower troposphere, north of 20°N low frequency waves lose energy through nonlinear triad interactions, unlike the upper troposphere where gain of energy is noticed. Longitude-frequency distributions suggest that wave-CISK process and strong gradient of SST are the possible mechanisms for the strong energy interactions associated with low frequency waves in the lower troposphere over the west Pacific and east coast of Africa, respectively. The study may aid investigation of the rapid loss of predictability of low frequency modes over the tropics.     

Spacetime dynamics of bed forms due to turbulence around submerged bridge piers

Stochastic Environmental Research and Risk Assessment - This work presents a study of spatiotemporal changes of scour-holes around sand embedded submerged circular and non-circular cylinders with...     

Migration of arsenic in multi-aquifer system of southern Bengal Basin: analysis via numerical modeling

A heterogeneous anisotropic steady-state groundwater flow model for the multi-aquifer system of a part of southern Bengal Basin shows that human intervention has changed the natural groundwater flow system. At present, the shallow groundwater flow is restricted within the aquifer, with very short travel time of tens of years and vertical path length. The deep aquifer is fed by surface water or rainwater from distant locations with travel time of thousands of years and has no hydraulic connection with the arsenic-rich shallow aquifer. Numerical simulations indicate that the future pumping of deep groundwater is not likely to drive in arsenic from the shallow aquifer. Therefore, new wells may be installed in the deep aquifer. High pumping of shallow unpolluted aquifer consisting of brown sand will drive in groundwater containing organic matter from the post-Last Glacial Maximum aquifer-aquitard system. The organic matter drives reduction of manganese oxides at strip interfaces between palaeo-channel and palaeo-interfluve. After the completion of manganese reduction, FeOOH reduction may take place in the marginal palaeo-interfluvial aquifer and release sorbed arsenic. Arsenic then moves into the interior of palaeo-interfluvial aquifer polluting its fresh groundwater. Arsenic migration rates ranges between 0.21 and 6.3 and 1.3 × 10^?2 and 0.4 m/year in horizontal and vertical directions, respectively. Therefore, palaeo-interfluvial aquifer will remain arsenic-free for hundreds to thousands of years to supply safe drinking water.     

A coupled model analyses on the interaction between oceanic eddies and tropical cyclones over the Bay of Bengal

Ocean Dynamics - The Bay of Bengal (BOB) region of Indian Ocean is affected by numerous tropical cyclones during pre- and post-monsoon seasons when various eddies are generated in the central and...     

Geological features and origin of the chromite deposits of sukinda valley,Orissa, India

The chromiferous ultramafic rocks of Sukinda Valley (21°0'–21°5'N:85°43'–86°0'E) of Orissa are intrusive into the Iron-Ore Supergroup (2,950–3,200 Ma) at the eastern periphery of the Indian Precambrian shield. Both laterally and vertically, chromite occurs as persistent layers, lenses or pockets in the serpentinized and silicified dunite-peridotite extending over a strike length of 25 km. The ultramafic rocks and the chromitite layers are cofolded with the Iron-Ore Supergroup into a plunging syncline. Primary layering, ball and pillow structures, cross laminations, graded bedding etc. can also be detected. The different varieties of chromite ore present in the area are massive, banded and spotted, laminated and friable. The grain size of chromite varies between 0.25 and 4 mm, and the fineness of the grain increases from the bottom to the top layers. The cell dimension of chromite (8.23–8.32 Å) decreases with the increase of Al₂O₃.Cr₂O₃ in pure chromite varies between 48 to 61 wt. percent, Al₂O₃ is 7.10–15.09 wt. percent, whereas Fe₂O₃ is very low (0.03–3.20 wt. percent). The amount of RO to R₂O₃ varies within a narrow limit of 0.98–1.13, indicating that the chromite is chemically balanced. The FeO to MgO ratio is intermediate between the stratiform and alpine type. Fe³⁺ and Al³⁺ increase with respect to Cr³⁺ and Mg²⁺ in the upper chromitite layers. TiO₂ lacks significant correlation with the major element composition of chromite.It is concluded that the Sukinda Valley chromitites of Orissa are predominantly stratiform in nature and were presumably formed in situ by crystal settling, the layering having been accentuated by the fluctuation of FO₂. The geological features suggest a single magmatic cycle.