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Singh, Puyam S.
- Treatment of Wastewater Containing Volatile Organics Using Hollow Fibre PDMS-Polysulfone Membrane System:Recovery of Organics and Water Reclamation
Abstract Views :235 |
PDF Views:88
Authors
Affiliations
1 CSIR-Central Salt and Marine Chemicals Research Institute, RO Membrane Discipline, G.B. Marg, Bhavnagar 364 002, IN
1 CSIR-Central Salt and Marine Chemicals Research Institute, RO Membrane Discipline, G.B. Marg, Bhavnagar 364 002, IN
Source
Current Science, Vol 111, No 3 (2016), Pagination: 517-523Abstract
Chlorinated volatile organic compounds (VOCs) from industrial facilities cause serious environmental problems. VOCs present in industrial wastewater are highly toxic to humans but can be valuable if it is recovered safely. A large membrane surface area is required for the treatment of dilute aqueous effluents containing dissolved VOCs. Hollow fibre membrane systems can provide a large membrane surface area per unit module. Here, we study the preparation of PDMS-polysulfone hollow fibre membrane system for application in separation of volatile organics from the aqueous stream. Dichloromethane, chloroform and dichloroethane of 300-5000 ppm in water, is used as model feed solution of aqueous effluent for the experiments. The results demonstrate that dissolved organics could be efficiently recovered from the aqueous stream, along with reclamation of water using the hollow fibre membrane system.Keywords
Hollow Fibre Membrane System, Organic Recovery, Volatile Organic Compounds, Wastewater, Water Reclamation.Full Text
- Aqueous Micellar Solution to Control Non-Solvent-Solvent Exchange during Phase Inversion Process of Polysulfone Membrane Preparation Resulting in Membranes of Different Pore Structures
Abstract Views :266 |
PDF Views:92
Authors
Affiliations
1 CSIR Central Salt and Marine Chemicals Research Institute, RO Membrane Division, G.B. Marg, Bhavnagar 364 002, IN
1 CSIR Central Salt and Marine Chemicals Research Institute, RO Membrane Division, G.B. Marg, Bhavnagar 364 002, IN
Source
Current Science, Vol 110, No 8 (2016), Pagination: 1485-1494Abstract
The study reports the preparation of polysulfone membranes of very precise and uniform pores and pore size distribution. The concentration of N,Ndimethylformamide (DMF) and sodium dodecyl sulphate (SDS) surfactant in the coagulation bath played a vital role in pore formation during phase inversion process. Polysulfone membranes of narrow pore size distribution with median pores at about 0.04-0.06 m were obtained.Keywords
Casting Process, Polysulfone Membrane, Micellar Solution Bath, Narrow Pore Size Distribution.Full Text
- Three-Dimensional Point Cloud Segmentation Using a Combination of RANSAC and Clustering Methods
Abstract Views :122 |
PDF Views:68
Authors
Puyam S. Singh
1,
Iainehborlang M. Nongsiej
2,
Valarie Marboh
2,
Dibyajyoti Chutia
1,
Victor Saikhom
1,
S. P. Aggarwal
1
Affiliations
1 North Eastern Space Applications Centre, Department of Space, Government of India, Umiam 793 103, IN
2 Department of Computer Science, St Anthony’s College, Shillong 793 001, IN
1 North Eastern Space Applications Centre, Department of Space, Government of India, Umiam 793 103, IN
2 Department of Computer Science, St Anthony’s College, Shillong 793 001, IN
Source
Current Science, Vol 124, No 4 (2023), Pagination: 434-441Abstract
There are challenges in performing 3D scene understanding on point clouds derived from drone images as these data are highly unstructured with no neighbouring information, highly redundant making the processing difficult and time-consuming and have variable density making it difficult to group and segment them. For proper scene understanding, these point clouds need to be segmented and classified into different groups representing similar characteristics. The approaches for segmentation differ based on the distinctiveness of each data product. Although newer machine learning-based approaches work well, they need large amounts of standardized labelled data which in turn require extensive resources and human intervention to obtain good results. Considering these, we have proposed a hybrid clustering-based hierarchical model for effective segmentation of dense 3D point cloud. We have applied the model to local data having a mix of man-made and natural vegetation with variable topography. The combination of RANSAC, DBSCAN and Euclidean method of cluster extraction proved to be useful for precise segmentation and classification of point clouds. The performance of the model has been assessed using Davies–Bouldin dbIndex-based intrinsic measures. The hybrid approach is able to segment 91% of the point clouds precisely compared to the conventional one-step clustering approach.Keywords
Clustering, Drone Images, Hierarchical Model, Three-Dimensional Point Cloud, Segmentation.Full Text
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