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Das  Subhrangsu  Das  Nirmalya  Chatterjee  Uday  Guchhait  Santu 《GeoJournal》2021,87(4):389-411

The provision of urban service and citizens’ satisfaction is an important key issue in urban planning. Importance-performance analysis (IPA) is an effective and widely applicable technique to explore consumer’s satisfaction. IPA helps to prioritize the management strategies for urban services using the IPA. Purpose of the present study is to assess the performance of urban services and citizen’s satisfaction level of Panskura municipality using IPA models and improvement index. A total of 629 valid household responses are collected with the help of the door-to-door primary survey technique. The study reveals that all the selected seven urban services have significant importance-performance gap except water supply. Residents of the Panskura municipality are very much satisfied with the water supply service because of the very minimum improvement score. The combined result of IPA matrices and improvement index suggests residents are dissatisfied to a great extent with the performance of four urban services, i.e. health, economy, transportation and sanitation. These urban services require a problem-solving urgent action for restoration of the performance status. The improvement and prioritization of urban service are also required to fulfil the demand of target groups.

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The cruise conducted in the spring inter-monsoon (pre-monsoon) of April 2015 in the frame of a funded project epitomized an open ocean survey that allowed procuring a quasi-synoptic picture of cyclopoid copepod community structure in 18 open ocean stations of the Minicoy Island, Lakshadweep archipelago, off the southwestern Indian coast, based on the analysis of standing stock and composition in the integrated 0–10 m water column. The main objective was to explore the community structure of cyclopoid copepods prevailing here and which environmental variable influences the same. It is witnessed that sea surface temperature (SST) (30.42 ± 0.19°C), sea surface salinity (SSS) (33.56 ± 1.15 psu), and dissolved oxygen (DO) (4.32 ± 0.06 ml/L) with SSS and DO are the best matching variables diversifying cyclopoid copepod species (av. abundance 700 ± 386 no. of individuals/100 m3). Average zooplankton biomass (0.03 ml/m3) and abundance (8,989 ± 3,866 no. of individuals/100 m3) were also observed. Fifty-one cyclopoid copepod species belonging to four families and seven genera were identified, with the dominance of high saline species such as Sapphirina, Copilia, Farranula, and Oncaea. An abundance biomass curve (ABC) plot analysis indicated an undisturbed community with normal environmental conditions. TAXDTEST (taxonomic distinctness) depicted a diverse condition where all points clustered together within a 95% confidence level. Our results indicate that the cyclopoid copepod assemblage near Minicoy Island is a diverse, undisturbed community and hypothesize that the stable environmental conditions during pre-monsoon (spring inter-monsoon) preferred the diversification of cyclopoid copepods with the prevalence of high saline species. The data evolved could be used as a standard reference/benchmark to detect any deviation from an undisturbed/diverse community status of Minicoy Island in the looming scenario of climate change in and around the Indian Ocean.  相似文献   
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Damping of water waves by a vertical porous structure placed at some distance from a vertical wall is investigated within the framework of linear water wave theory. The rectangular porous structure is placed on a small rectangular elevation. An incident wave of small amplitude propagates through the structure – some portion gets reflected back while some portion gets transmitted to a third region bounded vertically by a rigid wall which is considered to be at a distance near the porous structure, and also away from the wall at a large distance as a separate case. Boundary value problems are set up in all three regions and, by using the matching conditions along the vertical boundaries, a system of linear equations is deduced. The roots of the relevant dispersion relation are used in setting up the system of equations. The overall scattering phenomenon is studied with respect to different relevant parameters. The dependence of the coefficients on the thickness (width) of the porous structure is investigated for different numbers of modes and porosity. It is observed that, except for the case when the porous structure is thin, the reflection and transmission coefficients give rise to values as expected. In the case, when the rigid wall is nearer to the structure, the reflection coefficient decreases rapidly for a thin structure and converges for all numbers of evanescent modes afterwards. The transmission coefficient also decreases as the width increases, ultimately converging and vanishing for a wide structure. When the wall is at a large distance away from the structure, the behavior of both the reflection and transmission coefficients remain the same. For both cases of the wall being nearer and away from the structure, higher porosity gives rise to lower reflection coefficients and higher transmission coefficients. However, the transmission coefficients converge and vanish when the porous structure is very wide. We also discuss the energy loss against the width of the porous structure for different values of number of modes and porosity. Irrespective of the positioning of the rigid wall, we observe that for higher values of porosity, energy loss is more pronounced when the structure is not thin, whereas energy loss is same for all numbers of modes. All our observations are supported by graphs. Good agreement of our result with earlier results justifies our model.  相似文献   
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Our study interprets large-scale gravity data to delineate concealed banded iron formation (BIF) iron mineralization in India's Rajasthan province. The study area belongs to the Bharatpur, Dausa, and Karauli districts of Rajasthan. We measured 1462 gravity readings to understand the rock types, depth and geometry of the different rock formations in the proposed study area. We also collected representative lithologies from more than 100 locations in the study area and calculated their density values. The measured gravity datasets are investigated via qualitative (e.g., Bouguer anomaly, first derivative and second derivative) and quantitative (radially averaged power spectrum, 3D Euler deconvolution, and 3D inversion) approach. The qualitative methods suggest a general NE–SW orientation of the BIFs, controlled by the general trend of the study area's structural setting. The lithological contact between the Bhilwara and Vindhyan Supergroups is demarcated by a NE–SW trending steep gravity gradient zone. In this area, representative lithologies yield high densities (about 3.746 gm/cc), and the samples identified as BIF represent exploration targets for iron ore. We have also developed our own in-house 3D gravity inversion code in this study. A model space inversion algorithm is converted into a data space using the identity relationship. It makes inversion algorithm very user-friendly on conventional desktop computers. The outcomes from the 3D inversion suggest that the concealed iron ore thickens to the west. This interpretation is also in good correlation with Euler 3D deconvolution of the gravity data.

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