Time filter

Source Type

Abdullah Sohl M.,Stuttgart University of Applied Sciences | Abdullah Sohl M.,National Engineering Services Pakistan Pvt Ltd | Schlager P.,University of Hohenheim | Schlager P.,Armenian National Agrarian University | And 2 more authors.
Photogrammetric Engineering and Remote Sensing | Year: 2015

The present study is aimed at developing a methodology to extract maize, a predominant energy crop, and efficiently map its spatial distribution in a Natura 2000 region of northern Germany. Following a GEOBIA approach, segmentation was performed on two hierarchical levels. Level 1 consisted of field boundaries, and level 2 represented variations within level 1. Decision rules were developed for level 2 based on spectral information, vegetation indices, standard deviations and knowledge of crop phenology. For this purpose, first, level 2 image objects were classified. Subsequently classification was shifted to level 1. Maize covered 10.6 percent of total study area. The presented methodology gives the advanced user the flexibility to integrate expert knowledge in the classifier. In addition, the implementation time of decision rules was very fast and helped to produce results with high accuracy. © 2015 American Society for Photogrammetry. Source

Rafique H.M.,University of Punjab | Abbas I.,United Nations Development Programme | Sohl M.A.,National Engineering Services Pakistan Pvt Ltd | Shehzadi R.,University of Punjab | And 5 more authors.
Desalination and Water Treatment | Year: 2014

The quality of drinking water is vital for humans in order to remain alive, healthy and disease free. Consequently, it is indispensible to make sure that the available drinking water is uncontaminated. This study aimed at finding the quality of drinking water in Jampur, which is one of the tehsils of district Rajanpur in South Punjab, Pakistan. Thirty water samples were collected from different locations of the study area. These samples were gathered from different sources such as hand pump, injector pump, tube well and water supply line. The water quality was examined by comparing its standards with World Health Organization provided guidelines. It was found that majority of the Jampur's population were using contaminated water, which is very harmful and alarming. This contaminated water could cause a potential risk to people's health through many waterborne and skin diseases. The contamination of water could be due to dissolved contaminants and excessive ions such as arsenic, sodium, calcium or nitrate, etc. It is recommended that safety measures should be taken before exploiting this water for drinking. For the purification of contaminated water, filtration plants must be installed in the region. © 2013 Balaban Desalination Publications. All rights reserved. Source

Abbas I.,United Nations Development Programme | Rafique H.M.,University of Punjab | Sohl M.A.,National Engineering Services Pakistan Pvt Ltd | Falak A.,University of Punjab | And 5 more authors.
Desalination and Water Treatment | Year: 2014

The study investigates the spatial and temporal variation of groundwater table within municipal precincts of Rawalpindi metropolitan city. The research was based on current and historic withdrawals as a primary source of drinking water supply. A geodatabase of 278 tube wells with three distinct timelines of recorded subsurface water levels was developed. Vertical sections were extracted from the interpolated surfaces and reconciled to a common x, y reference to isolate spatial and temporal trend of water table. Over exploitation of groundwater is leading to progressive depletion of the groundwater resource. The decline in groundwater level was observed to be steep in areas farthest from the potential recharge zones, a phenomenon that is also coincident with the density of the installed wells. Gradual cessation of pumpage within the metropolitan area and artificial means of replenishing the groundwater aquifer are recommended. © 2013 © 2013 Balaban Desalination Publications. All rights reserved. Source

Shehzadi R.,University of Punjab | Rafique H.M.,University of Punjab | Abbas I.,Institute of Geographic Information System | Sohl M.A.,National Engineering Services Pakistan Pvt Ltd | And 3 more authors.
Desalination and Water Treatment | Year: 2015

Abstract: Poor quality of drinking water is one of the major threats to human health. Several potential sources such as toxic chemicals, minerals, effluent outfalls from industrial facilities, waste treatment plants, and run-off from agricultural land can contaminate drinking water. To ensure the accessibility of uncontaminated and safe drinking water, its quality should be managed and monitored carefully on a regular basis. A research study was conducted to evaluate the quality of drinking water in tehsil Alipur of district Muzaffargarh, Pakistan. Water samples were collected from different sources such as tube well, hand pump, injector pump, and water supply line from 27 different locations during 2007. The samples were examined for physical, chemical, and bacteriological contamination. Five physical parameters (pH, turbidity, hardness, total dissolved solids, and conductivity) and chemical parameters including sodium, calcium, magnesium, potassium, chloride, nitrate, sulfate, and bicarbonate were tested for each sample and values were compared with the standards set by WHO. The results revealed that physical and chemical parameters for majority of the samples were inside the acceptable limits of WHO for drinking water. However, the study of microbial quality of water showed that, about half of the samples were bacteriologically contaminated and thus unfit for human consumption. © 2014 Balaban Desalination Publications. All rights reserved. Source

Shakir A.S.,University of Engineering and Technology Lahore | Maqbool N.,National Engineering Services Pakistan Pvt Ltd
Irrigation and Drainage | Year: 2011

The paper reviews the problems being faced by the Upper Chenab Canal (UCC) and reports on the existing conditions assessed during various site visits. The water availability in the River Chenab at the Marala Barrage has been analysed based on the previous 20 years of recorded data in order to explore possible options for remodelling this canal. The visit report indicated that the UCC is faced with numerous problems such as bank erosion, bed scouring, side embayment, inadequate freeboard, abnormal behaviour and the deterioration of old hydraulic structures. Deferred maintenance and lack of proper and timely monitoring seem to be the main factors in the continuation of these problems in the canal. The water requirements at the head of the canal have been worked out as 562m3 s-1, nearly 20% higher than the present capacity (477m3 s-1). The study shows that the required amount of water is available for more than 90 days during the peak demand at 80% reliability for irrigation, hydropower generation and inter-river transfer to the River Ravi upstream of Balloki headworks for feeding its offtaking channels. The analysis also shows that the existing canal section is insufficient to pass the required discharge and needs to be remodelled to meet the requirements. This can be achieved by revising the canal section using a comprehensive design approach best suited to the local conditions. © 2010 John Wiley & Sons, Ltd. Source

Discover hidden collaborations