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  • 51.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Ali, Salahalddin
    University of Sulaimani, Kurdistan Region.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Classification of groundwater based on irrigation water quality index and GIS in Halabja Saidsadiq basin, NE Iraq2016In: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 24, article id 5Article in journal (Refereed)
    Abstract [en]

    Assessment of groundwater for irrigation purpose is proposed using the Irrigation Water Quality Index (IWQI) within the GIS environment. The model was applied to several aquifers in the study basin. Water samples were collected from thirty-nine sites from both water wells and springs from the dry season (September 2014) and the wet season (May 2015). Samples were tested chemically and physically for several variables: EC, Ca+2, Mg+2, Cl-, Na+ and HCO3- and SAR. The accuracy and precision methods were applied to find out the uncertainty of the chemical analysis results and its validity of application for the geochemical interpretations. Based on the spatial distribution of IWQI, the groundwater quality of HSB classified into several classes of both dry and wet seasons in terms of its restrictions on irrigation purposes. The classes include, Severe Restriction (SR), High Restriction (HR) and Moderate Restriction (MR). The coverage areas of all three classes are 1.4%, 52.4% and 46.2% for the dry season and 0.7%, 83.3% and16% for wet seasons respectively. The considerable variations in all these classes have been noted from dry to wet seasons, this might be related to increasing the aquifer recharges from precipitation and decreasing the aquifer discharges by the consumers in the wet season. Then the model was validated based on the relation between the aquifer recharge and spatial distribution of IWQI, the result of this validation confirmed the outcome of this study.

  • 52.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Ali, Salahalddin
    University of Sulaimani.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Groundwater Vulnerability Mapping Using Lineament Density on Standard DRASTIC Model: Case Study in Halabja Saidsadiq Basin, Kurdistan Region, Iraq2015In: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 7, no 10, p. 644-667Article in journal (Refereed)
    Abstract [en]

    Groundwater is the most important source of water in the Halabja-Saidsadiq Basin. In this study, to generate a map of groundwater pollution vulnerability of the basin, the standard DRASTIC method has been applied. Due to the close relation between lineament density and groundwater flow and yield, the lineament density map was applied to the standard DRASTIC model in order to ensure accuracy towards the consideration of the effects of potential vulnerability to contamination. A lineament map is extracted from Enhanced Thematic Mapper plus (ETM+) satellite imagery using different techniques in remote sensing and GIS. The lineament density map illustrates that only six classes of lineament density can be identified ranged from (0 - 2.4). The lineament density map was rated and weighted and then converted to lineament index map. This index map is an additional parameter which was added to the standard DRASTIC model so as to map the modified DRASTIC vulnerability in HSB. The standard vulnerability map, classified the basin into four vulnerability index zones: very low (34%), low (13%), moderate (48%) and high (5%). While the modified model classified the area into four categories as well: very low (28.75%), low (14.31%), moderate (46.91%) and high (10.04%). The results demonstrate that there is no significant variation in the rate of vulnerability. Therefore, the nitrate concentration between two different seasons (dry and wet) was analyzed from (30) water wells, considerable variations in nitrate concentration from dry to wet seasons had been noted. Consequently, it confirmed that the HSB are capable to receive the contaminant because of suitability in terms of geological and hydrogeological conditions. Based on this verification, it could be claimed that the effect of lineament density is weak on the vulnerability system in HSB, because of its low density value.

  • 53.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Ali, Salahalddin
    University of Sulaimani, Sulaymaniyah.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Groundwater Vulnerability Using DRASTIC and COP Models: Case Study of Halabja Saidsadiq Basin, Iraq2016In: Engineering, ISSN 1947-3931, Vol. 8, no 11, p. 741-760Article in journal (Refereed)
    Abstract [en]

    To avoid groundwater from contamination, the groundwater vulnerability tool can be examined. In this study, two methods were applied, namely: DRASTIC (Groundwater depth, Net recharge, Aquifer media, Soil map, Topography, Impact of vadose zone and Hydraulic Conductivity) and COP (Concentration of flow, Overlying layer and Precipitation) to model groundwater vulnerability to pollution. The result illustrated that four vulnerability classes were recognized based on both models including very low, low, moderate and high vulnerability classes. The coverage areas of each class are (34%, 13%, 48% and 5%) by DRASTIC model and (1%, 37%, 2% and 60%) by COP model, respectively. The notable dissimilarity between these two models was recognized. For this reason, nitrate elements were selected as a pollution indicator to validate the result. The concentrations of nitrate were recorded in two following seasons in (30) watering wells; as a result, the substantial variation was noted. This indicates that contaminants can be easily reached the groundwater due to its suitability in geological and hydrogeological conditions in terms of contaminant transportation. Based on this confirmation, the standard DRASTIC method becomes more sensible than COP method.

  • 54.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. Department of Geology, University of Sulaimani.
    Ali, Salahalddin
    Department of Geology, University of Sulaiman.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Possibility of Groundwater Pollution in Halabja Saidsadiq Hydrogeological Basin, Iraq Using Modified DRASTIC Model Based on AHP andTritium Isotopes2018In: Geosciences, ISSN 2076-3263, Vol. 8, no 7, article id 236Article in journal (Refereed)
    Abstract [en]

    An anthropogenic activity is one of the most severe environmental causes for groundwatercontamination in the urban area. Groundwater thought to be one of the principal sources of water supply in Halabja Saidsadiq Basin, and therefore its vulnerability evaluation to define areas that are more vulnerable to pollution is incredibly vital.  The objectives of this paper are to reveal weight modified of DRASTIC model based on the Analytical Hierarchical Process to estimate the proportional likelihood of groundwater resources pollution. Tritium isotopes analysis was chosen and applied as a pollution marker to confirm the result of this adjustment. Based on this modification, vulnerability classes that were achieved for the studied basin were alienated into five classes, including very low, low, medium, high, and very high, with vulnerability index value of (<100, >100–125, >125–150,>150–200, and >200), respectively.

  • 55.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Ali, Salahalddin
    University of Sulaimani, Kurdistan Region, NE Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Vulnerability of groundwater to pollution using three different models inHalabja Saidsadiq basin, Iraq2017In: Proceedings of the 10th World Congress of European Water Resources Association ‘Panta Rhei’, 5-9 July 2017, Athens, Greece / [ed] George Tsakisis, Vassilakos A. Tsihrintzis, Harris Vangelis, Dimitris Tigkas, Athens: European Water Resources AssociationSSOCIATION , 2017, p. 1827-1834Conference paper (Refereed)
    Abstract [en]

    Halabja Saidsadiq Basin (HSB) is one of a major basin of Iraq in terms of groundwater reservoirs. Intensive agricultural practices and economic revolution are widespread and located close to groundwater wells, which pose imminent threats to these resources. Therefore, the most effective and realistic solution is to prevent the contamination of groundwater through. The present study targets the computation of the vulnerability of groundwater reservoirs of the study area. Three methods have been examined, namely DRASTIC, VLDA and COP to model a map of groundwater vulnerability for contamination. The standard DRASTIC vulnerability maps classified the basin of four vulnerability index zones: very low (34%), low (13%), moderate (48%) and high (5%). The VLDA model also classified the area into four categories as well: low (2%), moderate (44%), high (53%) and very high (1%).Four vulnerability classes were recognized based on COP model including very low, low, moderate and high vulnerability classes with coverage areas of (1%, 37%, 2% and 60%) respectively. After constructing every vulnerability map, it required to be confirmed in order to estimate the validity of the theoretical sympathetic of current hydrogeological conditions. In this study, nitrate concentration analysis was selected as a contamination indicator to validate the result. Considerable variations in nitrate concentration on dry to wet seasons had been renowned. Consequently, it points toward that groundwater in the HSB are capable to receive the contaminant due to suitability of overlies strata in terms of geological and hydrogeological conditions. Based on this confirmation, the result exemplifies that the degree

    and distribution of vulnerability classes acquired using VLDA model is more sensible.

  • 56.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Ali, Salahalddin
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Vulnerability of groundwater to pollution using VLDA model in Halabja Saidsadiq Basin, Iraq.2016In: IWA Specialist Groundwater Conference: Conference Proceedings & Book of Abstracts, 09-11 June 2016, Belgrade Serbia / [ed] Milan A. Dimkic, Belgrade: Jaroslav Cerni Institute for the Development of Water Resources , 2016, p. 72-75Conference paper (Refereed)
    Abstract [en]

    Groundwater considered being the most vital source of water in several regions in the world. Specifically in the Halabja-Saidsadiq Basin, groundwater plays an important role as one of the essential source of water supplies. Therefore, it needs to be taken care of. In this study, VLDA method applied to model a map of groundwater vulnerability to contamination. The VLDA models classified the area into four categories with different coverage areas: low (2%), moderate (44%), high (53%) and very high (1%). After constructing every vulnerability map, it required to be confirmed in order to estimate the validity of the theoretical sympathetic of current hydrogeological conditions. In this study, nitrate concentration analysis was selected as a contamination indicator to validate the result. The nitrate concentration on two different seasons (dry and wet) was analyzed from (30) watering wells, considerable variations in nitrate concentration from dry to wet seasons had been noted. Consequently, it points toward that groundwater in the HSB are capable to receive the contaminant due to suitability of overlies strata in terms of geological and hydrogeological conditions. Based on this confirmation, the result exemplifies that the degree and distribution of vulnerability classes acquired using VLDA model is more sensible.

  • 57.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. Department of Geology, University of Sulaimani.
    Ali, Salahalddin S.
    University of Sulaimani, Kurdistan Region .
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Assessing the Vulnerability of Groundwater to Pollution Using DRASTIC and VLDA Modelsin Halabja Saidsadiq Basin, NE, Iraq2016In: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 10, no 10, p. 1144-1159Article in journal (Refereed)
    Abstract [en]

    Groundwater plays important roles as one of the essential source of water supplies of the studied area. Consequently, it needs to be prevented from contamination. In this study, two methods have been examined, namely DRASTIC (depth to groundwater, net recharge, aquifer media, soil map, topography, impact of vadose zone and hydraulic conductivity) and VLDA (vadose zone lithology, land use patterns, depth to groundwater and aquifer media) to model a map of groundwater vulnerability for contamination of the basin. The standard DRASTIC vulnerability maps classified the basin of four vulnerability index zones: very low (34%), low (13%), moderate (48%) and high (5%). While the VLDA model classified the area into four categories as well: low (2%), moderate (44%), high(53%) and very high (1%). The results demonstrate that there is a significant dissimilarity in the rate of vulnerability. Validation of the constructed maps is required to confirm the validity of the theoretical sympathetic of current hydrogeological conditions. In this study, nitrate concentration analysis was selected as a contamination indicator to validate the result. The nitrate concentration of two different seasons (dry and wet) was analyzed from (30) watering wells, considerable variations in nitrate concentration from dry to wet seasons had been noted. Consequently, it points toward that groundwater in the HSB (Halabja Saidsadiq Basin) is capable to receive the contaminant due to suitability of overlies strata in terms of geological and hydrogeological conditions. Based on this confirmation, the result exemplifies that the degree and distribution of vulnerability level acquired using VLDA model is more sensible than that attained from the standard DRASTIC method .In addition, the DRASTIC models need to be modified based on the land use pattern, which clarifies the role of human activity on the vulnerability system.

  • 58.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. Groundwater Directorate of Sulaimani, Kurdistan,Iraq.
    Ali, Salahalddin S.
    Department of Geology, University of Sulaimani,Kurdistan, Iraq. Komar University of Science and Technology, Iraqi Kurdistan , Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Hydrogeochemical Evaluation of Groundwater and Its Suitability for Domestic Uses in Halabja Saidsadiq Basin, Iraq2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 4, article id 690Article in journal (Refereed)
    Abstract [en]

    Evaluation of the hydrogeochemical characteristics and groundwater suitability for domestic use was conducted in the Halabja Saidsadiq Basin in the northeastern part of Iraq. The total studied area is about 1278 km 2 with a specific Mediterranean-type continental interior climate, which is cold in winter and hot in summer. To conduct the required laboratory chemical analysis for groundwater samples in the studied basin, 78 groundwater samples, in total, were collected from 39 water wells in the dry and wet seasons in 2014 and analyzed for major cations and anions, and the results were compared with the permitted limits for drinking water. An examination of the chemical concentrations of the World Health Organization drinking water norms demonstrate that a large portion of the groundwater samples is suitable for drinking, and a preponderance of groundwater samples situated in the class of hard and very hard water types for both seasons. Suitability of groundwater for drinking use was additionally assessed according to the water quality index classification. This showed that more than 98% of groundwater samples have good water quality in the dry and wet seasons. Conversely, the classification of groundwater samples based on Piper’s diagram designates that the groundwater type is alkaline water, with existing bicarbonate along with sulfate and chloride. However, water–ock exchange processes and groundwater flow have been responsible for the dominant water type of Ca–g–CO3.

  • 59.
    Abdullah, Twana O.
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. Department of Geology, University of Sulaimani, Kurdistan Region, NE..
    Ali, Salahalddin S.
    University of Sulaimani, Kurdistan Region, NE Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Vulnerability of groundwater to pollution using three different models in Halabja Saidsadiq basin, Iraq2017In: European Water, ISSN 1105-7580, Vol. 57, p. 353-359Article in journal (Refereed)
    Abstract [en]

    Halabja Saidsadiq Basin (HSB) is one of a major basin of Iraq in terms of groundwater reservoirs. Intensive agricultural practices and economic revolution are widespread and located close to groundwater wells, which pose imminent threats to these resources. Therefore, the most effective and realistic solution is to prevent the contamination of groundwater through. The present study targets the computation of the vulnerability of groundwater reservoirs of the study area. Three methods have been examined, namely DRASTIC, VLDA and COP to model a map of groundwater vulnerability for contamination. The standard DRASTIC vulnerability maps classified the basin of four vulnerability index zones: very low (34%), low (13%), moderate (48%) and high (5%). The VLDA model also classified the area into four categories as well: low (2%), moderate (44%), high (53%) and very high (1%). Four vulnerability classes were recognized based on COP model including very low, low, moderate and high vulnerability classes with coverage areas of (1%, 37%, 2% and 60%) respectively. After constructing every vulnerability map, it required to be confirmed in order to estimate the validity of the theoretical sympathetic of current hydrogeological conditions. In this study, nitrate concentration analysis was selected as a contamination indicator to validate the result. Considerable variations in nitrate concentration on dry to wet seasons had been renowned. Consequently, it points toward that groundwater in the HSB are capable to receive the contaminant due to suitability of overlies strata in terms of geological and hydrogeological conditions. Based on this confirmation, the result exemplifies that the degree and distribution of vulnerability classes acquired using VLDA model is more sensible.

  • 60.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Salahalddin, Ali
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Effect of Agricultural activities on Groundwater Vulnerability: Case Study of Halabja Saidsadiq Basin, Iraq2015In: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 23, no 10Article in journal (Refereed)
    Abstract [en]

    Groundwater is one of the main sources of water in Halabja-Saidsadiq Basin of northeast Iraq. It covers an area of 1278 square kilometers with population of about 190,727.In this study, the standard DRASTIC method has been applied to generate a map of groundwater pollution vulnerability of the basin. In addition, two different scenes of landsat Thematic Mapper (TM) were used with the aid of ERDAS IMAGINE software and the GIS technique to prepare digital image classification of the study basin. Supervised classification for level I of USGS was conducted with band combination RGB/742 to prepare The Land Use and Land Cover (LULC) map. The LULC map illustrates that only five classes of land use can be identified these are: barren, agricultural, vegetation, urban and wet land or water body. The LULC map converted to LULC index map. This index map has an additional parameter added to the standard DRASTIC model to map the modified DRASTIC vulnerability in the study basin. Nitrate concentration analysis was selected and added as a pollution indicator to validate this modification. In this study, the nitrate concentration between two different seasons (dry and wet) was analyzed from (30) water wells. The standard vulnerability map of the studied basin classified the basin into four vulnerability index zones: very low (34%), low (13%), moderate (48%) and high (5%). While the combined modification classified the area into five classes: very low (1.17%), low (36.82%), moderate (17.57%), high (43.42%) and very high (1.02%). The results s that the modified DRASTIC model was dramatically superior to the standard model; therefore, the most appropriate method to apply is the combination of standard DRASTIC model with LULC index map. This conclusion is based on the results of nitrate content, as its concentration in the dry season is much lower than in the wet season.

  • 61.
    Abedin, Md. Zainal
    et al.
    University of Science and Technology Chittagong.
    Chowdhury, Abu Sayeed
    University of Science and Technology Chittagong.
    Hossain, Mohammad Shahadat
    University of Chittagong, Bangladesh.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Karim, Razuan
    University of Science and Technology Chittagong.
    An Interoperable IP based WSN for Smart Irrigation Systems2017Conference paper (Refereed)
    Abstract [en]

    Wireless Sensor Networks (WSN) have been highly developed which can be used in agriculture to enable optimal irrigation scheduling. Since there is an absence of widely used available methods to support effective agriculture practice in different weather conditions, WSN technology can be used to optimise irrigation in the crop fields. This paper presents architecture of an irrigation system by incorporating interoperable IP based WSN, which uses the protocol stacks and standard of the Internet of Things paradigm. The performance of fundamental issues of this network is emulated in Tmote Sky for 6LoWPAN over IEEE 802.15.4 radio link using the Contiki OS and the Cooja simulator. The simulated results of the performance of the WSN architecture presents the Round Trip Time (RTT) as well as the packet loss of different packet size. In addition, the average power consumption and the radio duty cycle of the sensors are studied. This will facilitate the deployment of a scalable and interoperable multi hop WSN, positioning of border router and to manage power consumption of the sensors.

  • 62.
    Abedin, Md. Zainal
    et al.
    University of Science and Technology, Chittagong.
    Paul, Sukanta
    University of Science and Technology, Chittagong.
    Akhter, Sharmin
    University of Science and Technology, Chittagong.
    Siddiquee, Kazy Noor E Alam
    University of Science and Technology, Chittagong.
    Hossain, Mohammad Shahadat
    University of Chittagong, Bangladesh.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Selection of Energy Efficient Routing Protocol for Irrigation Enabled by Wireless Sensor Networks2017In: Proceedings of 2017 IEEE 42nd Conference on Local Computer Networks Workshops, Piscataway, NJ: Institute of Electrical and Electronics Engineers (IEEE), 2017, p. 75-81Conference paper (Refereed)
    Abstract [en]

    Wireless Sensor Networks (WSNs) are playing remarkable contribution in real time decision making by actuating the surroundings of environment. As a consequence, the contemporary agriculture is now using WSNs technology for better crop production, such as irrigation scheduling based on moisture level data sensed by the sensors. Since WSNs are deployed in constraints environments, the life time of sensors is very crucial for normal operation of the networks. In this regard routing protocol is a prime factor for the prolonged life time of sensors. This research focuses the performances analysis of some clustering based routing protocols to select the best routing protocol. Four algorithms are considered, namely Low Energy Adaptive Clustering Hierarchy (LEACH), Threshold Sensitive Energy Efficient sensor Network (TEEN), Stable Election Protocol (SEP) and Energy Aware Multi Hop Multi Path (EAMMH). The simulation is carried out in Matlab framework by using the mathematical models of those algortihms in heterogeneous environment. The performance metrics which are considered are stability period, network lifetime, number of dead nodes per round, number of cluster heads (CH) per round, throughput and average residual energy of node. The experimental results illustrate that TEEN provides greater stable region and lifetime than the others while SEP ensures more througput.

  • 63.
    Abedin, Md. Zainal
    et al.
    University of Science and Technology, Chittagong.
    Siddiquee, Kazy Noor E Alam
    University of Science and Technology Chittagong.
    Bhuyan, M. S.
    University of Science & Technology Chittagong.
    Karim, Razuan
    University of Science and Technology Chittagong.
    Hossain, Mohammad Shahadat
    University of Chittagong, Bangladesh.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Performance Analysis of Anomaly Based Network Intrusion Detection Systems2018In: Proveedings of the 43nd IEEE Conference on Local Computer Networks Workshops (LCN Workshops), Piscataway, NJ: IEEE Computer Society, 2018, p. 1-7Conference paper (Refereed)
    Abstract [en]

    Because of the increased popularity and fast expansion of the Internet as well as Internet of things, networks are growing rapidly in every corner of the society. As a result, huge amount of data is travelling across the computer networks that lead to the vulnerability of data integrity, confidentiality and reliability. So, network security is a burning issue to keep the integrity of systems and data. The traditional security guards such as firewalls with access control lists are not anymore enough to secure systems. To address the drawbacks of traditional Intrusion Detection Systems (IDSs), artificial intelligence and machine learning based models open up new opportunity to classify abnormal traffic as anomaly with a self-learning capability. Many supervised learning models have been adopted to detect anomaly from networks traffic. In quest to select a good learning model in terms of precision, recall, area under receiver operating curve, accuracy, F-score and model built time, this paper illustrates the performance comparison between Naïve Bayes, Multilayer Perceptron, J48, Naïve Bayes Tree, and Random Forest classification models. These models are trained and tested on three subsets of features derived from the original benchmark network intrusion detection dataset, NSL-KDD. The three subsets are derived by applying different attributes evaluator’s algorithms. The simulation is carried out by using the WEKA data mining tool.

  • 64.
    Abel, Frank
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Kuyumcu, Halit Z.
    TU Berlin.
    Einfluss verschiedener Parameter auf die Verdichtbarkeit und Festigkeit gestampfter Kohlekuchen2008Conference paper (Other academic)
  • 65.
    Abel, Frank
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Kuyumcu, Halit Z.
    Stamped coal cakes in cokemaking technology Part 1 - A parameter study on stampability2009In: Ironmaking & steelmaking, ISSN 0301-9233, E-ISSN 1743-2812, Vol. 36, no 5, p. 321-326Article in journal (Refereed)
  • 66.
    Abel, Frank
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Kuyumcu, Halit Z.
    TU Berlin.
    Stamped coal cakes in cokemaking technology Part 2 - The investigation of cake strength2009In: Ironmaking & steelmaking, ISSN 0301-9233, E-ISSN 1743-2812, Vol. 36, no 5, p. 327-332Article in journal (Refereed)
  • 67.
    Abel, Martin
    et al.
    University of Texas, Physics Department.
    Frommhold, Lothar
    University of Texas, Physics Department.
    Gustafsson, Magnus
    Department of Chemistry, University of Gothenburg.
    Collision-induced absorption at wavelengths near 5 μm by dense hydrogen gas2009In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 131, no 18, article id 181102Article in journal (Refereed)
    Abstract [en]

    Based on a recent ab initiointeraction-induced dipole surface of collisionally interacting molecular hydrogen pairs H2–H2, we compute the binary absorption coefficients at wavelengths near 5 μm at temperatures of 77.5 and 297 K for comparison with existing laboratory measurements. We observe satisfactory agreement of the measurements with our calculations, thereby concluding an earlier study [Gustafsson et al., J. Chem. Phys.119, 12264 (2003)], which was based on an ab initiointeraction-induced dipole surface that was inadequate for the 5 μm band.

  • 68.
    Abel, Martin
    et al.
    University of Texas, Physics Department.
    Frommhold, Lothar
    University of Texas, Physics Department.
    Wang, Fei
    Physics Department, Beijing Institute of Technology, China, University of Texas, Physics Department.
    Gustafsson, Magnus
    Department of Chemistry, University of Gothenburg.
    Li, Xiaoping
    Department of Chemistry, Michigan State University.
    Hunt, Katherine L.C.
    Department of Chemistry, Michigan State University, East Lansing, Department of Chemistry, Michigan State University.
    Collision-induced absorption by supermolecular complexes from a new potential energy and induced dipole surface, suited for calculations up to thousands of kelvin2010In: 20th International Conference on Spectral Line Shapes: St. John's, Newfoundland, Canada, 6 - 11 June 2010 ; [20th ICSLS] / [ed] John K.C. Lewis; Adriana Predoi-Cross, Melville, NY: American Institute of Physics (AIP), 2010, p. 251-257Conference paper (Refereed)
    Abstract [en]

    Absorption by pairs of H2 molecules is an important opacity source in the atmospheres of the outer planets, and thus of special astronomical interest. The emission spectra of cool white dwarf stars differ significantly from the expected blackbody spectra, amongst other reasons due to absorption by H2-H2, H2-He, and H2-H collisional complexes in the stellar atmospheres. To model the radiative processes in these atmospheres, which have temperatures of several thousand kelvin, one needs accurate knowledge of the induced dipole (ID) and potential energy surfaces (PES) of such collisional complexes. These come from quantum-chemical calculations with the H2 bonds stretched or compressed far from equilibrium. Laboratory measurements of collision-induced (CI) absorption exist only at much lower temperature. For H2 pairs at room temperature, the calculated spectra of the rototranslational band, the fundamental band, and the first overtone match the experimental data very well. In addition, with the newly obtained IDS it became possible to reproduce the measurements in the far blue wing of the rototranslational spectrum of H2 at 77.5 K, as well as at 300 K. Similarly good agreement between theory and measurement is seen in the fundamental band of molecular deuterium at room temperature. Furthermore, we also show the calculated absorption spectra of H2-He at 600 K and of H2-H2 at 2,000 K, for which there are no experimental data for comparison

  • 69.
    Abeysekera, John
    Luleå tekniska universitet.
    Diversified design needs of personal protective devices and clothing in cold climate: an example in the design needs of protective outdoor winter shoes2000In: Ergonomics of protective clothing: proceedings of NOKOBETEF 6 and 1st European conference on protective clothing held in Stockholm,Sweden, May 7-10, 2000 / [ed] Kalev Kuklane; Ingvar Holmér, Stockholm: Arbetslivsinstitutet , 2000, p. 62-66Conference paper (Refereed)
  • 70.
    Abeysekera, John
    Luleå tekniska universitet.
    Ergonomic problems outside work establishments in industrially developing countries: an example from Sri Lanka1997In: From experience to innovation: proceedings of the 13th triennial congress of the International Ergonomics Association, June 29 - July 4, 1997, Tampere, Finland / [ed] Pentt Seppälä, Taylor and Francis Group , 1997, p. 63-65Conference paper (Refereed)
  • 71.
    Abeysekera, John
    Luleå tekniska universitet.
    Ergonomics aspects of personal protective devices1993In: Occupational and environmental economics / [ed] Rabindra Nath Sen; Haripada Chattopadhyay; Subir Das, Indian Society of Ergonomics. , 1993, p. 109-114Conference paper (Refereed)
    Abstract [en]

    The use of a personal protective device (ppd) is a widely accepted method of safeguarding workers from occupational hazards in industrialized countries (IC) and an important method employed in developing countries (DC). Though protection is assured if the devices are worn constantly, it is unfortunate that due to discomfort and inconvenience, the majority of those exposed to hazards do not wear them. DCs which mainly import ppds from ICs are confronting many ergonomics problems, because the equipment designed for IC conditions is inappropriate for use in DCs, due to significant differences in user body sizes, environments and working methods. A questionnaire survey conducted among ppd manufacturers in 11 ICs revealed that 90% followed standards in manufacturing. Another survey conducted among health and safety authorities who responded on behalf of ppd users in 35 DCs revealed that the most common ergonomic causes of non-use are stresses from hotness, weight, improper fit and obstruction at work. While manufacturers place greater emphasis in the protection performance of the equipment, users in DCs refuse to wear it because the comfort needs are not fulfilled. Developing ergonomics standards for ppds seems to be a feasible way of persuading the manufacturers to provide ergonomic values in ppds. The need for maximum allowable comfort in the design, taking into consideration the user characteristics and protection factor is emphasized. To overcome the inherent discomforts that are extremely difficult to reduce without compromising the protection efficiency of a ppd, the principle of user adaptation seems to be a very important facet which has to be developed. A case study on safety helmets is reported. The use of a personal protective device (ppd) is a widely accepted method of safeguarding workers from occupational hazards in industrialized countries (IC) and an important method employed in developing countries (DC). Though protection is assured if the devices are worn constantly, it is unfortunate that due to discomfort and inconvenience, the majority of those exposed to hazards do not wear them. DCs which mainly import ppds from ICs are confronting many ergonomics problems, because the equipment designed for IC conditions is inappropriate for use in DCs, due to significant differences in user body sizes, environments and working methods. A questionnaire survey conducted among ppd manufacturers in 11 ICs revealed that 90% followed standards in manufacturing. Another survey conducted among health and safety authorities who responded on behalf of ppd users in 35 DCs revealed that the most common ergonomic causes of non-use are stresses from hotness, weight, improper fit and obstruction at work. While manufacturers place greater emphasis in the protection performance of the equipment, users in DCs refuse to wear it because the comfort needs are not fulfilled. Developing ergonomics standards for ppds seems to be a feasible way of persuading the manufacturers to provide ergonomic values in ppds. The need for maximum allowable comfort in the design, taking into consideration the user characteristics and protection factor is emphasized. To overcome the inherent discomforts that are extremely difficult to reduce without compromising the protection efficiency of a ppd, the principle of user adaptation seems to be a very important facet which has to be developed. A case study on safety helmets is reported.

  • 72.
    Abeysekera, John
    Luleå tekniska universitet.
    Human factors of personal protective devices1998In: Global ergonomics: proceedings of the Ergonomics Conference, Cape Town, South Africa, 9-11 September 1998 / [ed] Pat A. Scott; R.S. Bridger; Jack Charteris, 1998, p. 157-164Conference paper (Refereed)
  • 73.
    Abeysekera, John
    Luleå tekniska universitet.
    Masters program in ergonomics at Luleå University of Technology, Sweden2000In: International Journal of Industrial Ergonomics, ISSN 0169-8141, E-ISSN 1872-8219, Vol. 26, no 5, p. 569-570Article in journal (Other academic)
  • 74.
    Abeysekera, John
    Luleå tekniska universitet.
    Some ergonomics issues in the design of personal protective devices1992In: Performance of protective clothing: fourth volume / [ed] Norman W, Henry; James P. McBriarty, Philadelphia, Pa.: ASTM International, 1992, p. 651-659Conference paper (Refereed)
    Abstract [en]

    The use of personal protective devices (ppd) is an important method to safeguard workers from occupational hazards both in industrialized and developing countries. Surveys have indicated that majority of those exposed to hazards are reluctant to use ppd because they are uncomfortable for such reasons as hotness, heaviness, ill fit, inconvenient, etc. Investigations have revealed that user-centered designs which satisfy the human factors needs of ppd, can reverse this trend and make ppd more acceptable. Because a questionnaire survey has shown that manufacturers are more inclined to adhere to standards, developing ergonomic standards seems to be a feasible method to persuade the manufacturers to provide the user needs in the design. Any unavoidable discomforts in ppd can be controlled by adaptation of users to ppd wearing.  

  • 75.
    Abeysekera, John
    Luleå tekniska universitet.
    The 10th Anniversary Ergonomics Conference, 29-30 October, 1999 Luleå University of Technology, Sweden2000In: International Journal of Industrial Ergonomics, ISSN 0169-8141, E-ISSN 1872-8219, Vol. 36, no 5, p. 571-572Article in journal (Other academic)
  • 76.
    Abeysekera, John
    Luleå tekniska universitet.
    The use of personal protective clothing and devices in the cold environment1992Report (Other academic)
    Abstract [en]

    In the use of personal protective devices (ppd) in the cold environment the wearability problems become more aggravated as the ppd must be worn over the cold protective clothing. Research in the area of human factors of ppd in cold environment has been scarce in the past. The lack of adequate user needs in currently used ppd in the cold environment, has resulted in discomfort, injury, non-use, and performance decrement among outdoor workers, particularly in the extreme cold regions, viz. Arctic countries. A preliminary study on the 'state of the art' was carried out on the use of ppd in cold environment which consisted of a literature survey, questionnaire survey among outdoor workers and information search through visits to relevant research institutions, discussions with researchers and participation in Conferences. The literature search carried out in 6 data bases revealed useful information about specific areas where wearability problems exist in ppd as well as some methods to be employed in research. The results of the questionnaire survey carried out in the Luleå region confirm that workers confront many inadequacies in the use of ppd in the cold climate. From the findings of this preliminary study three important kinds of ppd viz. safety gloves, safety shoes and safety helmets are discussed in this report. Human factors research for ppd in the cold environment with a view for improvement of wearability and use seem urgent.

  • 77.
    Abeysekera, John
    et al.
    Luleå tekniska universitet.
    Alwis, W.R. de
    University of Colombo.
    Ergonomics in Sri Lanka: a means to productivity development1996In: 4th Pan-Pacific Conference on Occupational Ergonomics: Taipei, Taiwan. 11-14 Nov., 1996, Ergonomics society of Taiwan , 1996, p. 323-327Conference paper (Refereed)
    Abstract [en]

    Sri Lanka has declared 1996 as the 'Year of Productivity'. With a significant share of her national income being diverted for defence and security, productivity development becomes supreme for Sri Lanka's economic survival. Ergonomics or human factors which is a science well known for improving working conditions, is hardly known in Sri Lanka. Ergonomics applications enhance job satisfaction and productivity and maximise the product or systems quality by improving usability. A recent survey of three randomly selected large industrial work establishments in Sri Lanka revealed that much mismatch exists between workers and the machinery they are forced to work with, which hampers productivity and causes friction in the work places. A series of lectures conducted by an ergonomist among different professional groups and university students helped to create considerable awareness of the science of ergonomics. The participants were convinced that ergonomics can contribute immensely to productivity development in the country. Some strategies for ergonomics education in Sri Lanka which can also be adopted in other similar industrially developing countries are proposed.

  • 78.
    Abeysekera, John
    et al.
    Luleå tekniska universitet.
    Barabash, V.
    Human factors of clothing and work-wear: a review1994In: Proceedings: Second International Congress on Physiological Anthropology : September 12 - 16, 1994, University of Kiel, Germany, Kiel: German Society of Physiological Anthropology , 1994, p. 137-142Conference paper (Refereed)
    Abstract [en]

    An extraordinarily large share of research carried out in the near past on clothing comfort has been in the area of thermal comfort. Accordingly standards, norms and guidelines on thermal requirements of work-wear have been developed. Through behavioural adjustments people have learned to achieve thermal comfort even if the work clothes have slight deficiencies in thermal characteristics. It is beyond doubt that the thermal characteristics need careful consideration in the manufacture of work clothes. At the same time one must be aware that other human factors can also influence the overall wearability of clothing. This paper reviews the wearability and comfort of the clothing and work-wear to provide better understanding of the priorities in user needs in work clothes which can help plan future research and the need for new standards

  • 79.
    Abeysekera, John
    et al.
    Luleå tekniska universitet.
    Bergquist, Karin
    The need for research on human factors regarding personal protective devices in the cold environment1996In: Performance of protective clothing / [ed] James S. Johnson; S.Z. Mansdorf, West Conshohocken, Pa: ASTM International, 1996, Vol. 5Conference paper (Refereed)
    Abstract [en]

    The human factors or wearability needs of personal protective devices (ppd) and clothing (ppc) worn in the cold environment become more important as they must compromise with, and be adapted to, the clothing worn for cold protection. The occupational risks among outdoor workers in the cold can be aggravated if the wearability demands of ppd are not met. Failure to adequately meet user needs in currently used ppd in the cold environment has resulted in discomfort, injury, non-use and performance decrement among outdoor workers, particularly in the extreme cold regions. A preliminary study consisting of a literature survey in popular data bases and questionnaire survey among users of ppd, were carried out to ascertain what studies have already been conducted in this area and whether a wearability problem really exists among users, respectively. The literature revealed some specific areas where wearability problems exist and some research carried out on methods of testing of ergonomic characteristics of ppd. The questionnaire among ppd users in the cold climate confirmed that the workers do confront many inadequacies in the use of ppd. A case study carried out on ergonomic demands of safety shoes in the cold climate among users, manufacturers and experts revealed a similar trend of demands and priorities in ergonomics of shoes among all three groups. From the findings of the preliminary study it can be concluded that human factors research in ppd and particularly ppd worn on body extremities, viz. safety helmets, shoes and gloves, for use in the cold environment, seem urgent. Some research needs in the development of methods of testing for ppd evaluation are suggested

  • 80.
    Abeysekera, John D.
    Luleå tekniska universitet.
    Thermal environment and subjective discomfort of glass-factory workers in Sri Lanka1981In: Journal of Human Ergology, ISSN 0300-8134, Vol. 10, no 2, p. 185-92Article in journal (Refereed)
  • 81.
    Abeysekera, John D.A.
    Luleå tekniska universitet.
    A comparative study of body size variability between people in industrialised countries and industrially developing countries, its impact on the use of imported goods1987In: Ergonomics in developing countries: international symposium : proceedings : Jakarta, Indonesia, 18-21 November 1985, Geneva: Arkansas Philological Association, 1987, p. 65-91Conference paper (Refereed)
  • 82.
    Abeysekera, John D.A.
    Luleå tekniska universitet.
    Ergonomic aspects of personal protective devices in industrially developing countries1989Doctoral thesis, comprehensive summary (Other academic)
  • 83.
    Abeysekera, John D.A.
    Luleå tekniska universitet.
    Ergonomics and technology transfer1990In: International Journal of Industrial Ergonomics, ISSN 0169-8141, E-ISSN 1872-8219, Vol. 5, no 2, p. 181-184Article in journal (Refereed)
  • 84. Abeysekera, John D.A.
    Ergonomics for effective collaboration1997In: African Newsletter on Occupational Health and Safety, ISSN 0788-4877, no 2, p. 27-Article in journal (Other academic)
  • 85.
    Abeysekera, John D.A.
    Luleå tekniska universitet.
    The Need for National and International Ergonomics Standards for Personal Protective Devices1989In: Advances in industrial ergonomics and safety 1: proceedings of the annual International Industrial Ergonomics and Safety Conference held in Cincinnati, Ohio, U.S.A., 5-9 June 1989 / [ed] Anil Mital, London: Taylor and Francis Group , 1989, p. 809-816Conference paper (Refereed)
  • 86.
    Abeysekera, John D.A.
    et al.
    Luleå tekniska universitet.
    Holmér, Ingvar
    National Institute for Working Life.
    Dupuis, Christer
    Heat transfer characteristics of industrial safety helmets1991In: Towards human work: solutions to problems in occupational health and safety, London: Taylor and Francis Group , 1991, p. 297-303Chapter in book (Other (popular science, discussion, etc.))
  • 87.
    Abeysekera, John D.A.
    et al.
    Luleå tekniska universitet.
    Khan, Z.
    Slipping and falling accidents on icy surfaces: a case study from northern Sweden1998In: Problems with cold work: proceedings from an international symposium held in Stockholm, Sweden, November 16-20, 1997 / [ed] Ingvar Holmér; Kalev Kuklane, Solna: Arbetslivsinstitutet , 1998, p. 201-204Conference paper (Refereed)
  • 88.
    Abeysekera, John D.A.
    et al.
    Luleå tekniska universitet.
    Liu, Xiaoxiong
    A Scandinavian perspective on human factors testing of personal protective devices1997In: Performance of protective clothing: sixth volume ; [papers presented at the Sixth International Symposium on the Performance of Protective Clothing: Emerging Protection Technologies held in Orlando, Florida on 18 - 19 June 1996] / [ed] Jeffrey O. Stull; Arthur D. Schwope, West Conshohocken, Pa: ASTM International, 1997, p. 283-292Conference paper (Refereed)
    Abstract [en]

    Testing for protection performance and human factors in personal protective devices (PPD) can be undertaken using a standardised methodology. The standardised methodology for performance testing is used for the certification of PPD. However, it is unfortunate that methods of testing for human factors and wearability of PPD are scarce, and even the methods that do exist are not always refined or standardised. In both hot and cold environments, thermal comfort is an important user need of PPD. To test the thermal characteristics of PPD, methods providing objective data are available, yet they are not always standardised. An exception exists for insulation testing of clothing, for which standardised methods have been developed. The fit of PPD is also a priority need among wearers. Clothing fit is often tested subjectively. The objective methods developed to test the fit of PPD and clothing again require refinement and standardisation. Wearability of PPD urgently requires the development and standardisation of both objective and subjective testing methods. This paper provides insights into some testing methods on human factors of PPD that have been particularly useful over the years.

  • 89.
    Abeysekera, John D.A.
    et al.
    Luleå tekniska universitet.
    Shahnavaz, Houshang
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    A brief guide to questionnaire design: with examples from ergonomics1985Report (Other academic)
  • 90.
    Abeysekera, John D.A.
    et al.
    Tekniska högskolan i Luleå, CEDC.
    Shahnavaz, Houshang
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    A head-model reconstruction based upon photogrammetric data from Sri Lankan adult males relevant to the design of headgear1989In: Journal of Human Ergology, ISSN 0300-8134, Vol. 18, no 2, p. 199-211Article in journal (Refereed)
    Abstract [en]

    Due to the large variability in heads and faces in one population, the standard anthropometric dimensions of the head, measured from anatomical landmarks alone, may not suffice for the design of fitting headgear, e.g., helmets. To provide adequate data of the shapes and contours of the head to the designer, appropriate head models sculptured using comprehensive head dimensions, must be developed. This paper describes (a) a procedure of collecting comprehensive anthropometric data of the head using a photogrammetric method and (b) a simple sculpturing technique to reconstruct a head model of the user population

  • 91.
    Abeysekera, John D.A.
    et al.
    Luleå University of Technology.
    Shahnavaz, Houshang
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Body size data of Sri Lankan workers and their variability with other populations in the world: its impact on the use of imported goods1987In: Journal of Human Ergology, ISSN 0300-8134, Vol. 16, no 2, p. 193-208Article in journal (Refereed)
  • 92.
    Abeysekera, John D.A.
    et al.
    Tekniska högskolan i Luleå, CEDC.
    Shahnavaz, Houshang
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Body size variability between people in developed and developing countries and its impact on the use of imported goods1989In: International Journal of Industrial Ergonomics, ISSN 0169-8141, E-ISSN 1872-8219, Vol. 4, no 2, p. 139-149Article in journal (Refereed)
    Abstract [en]

    The Industrially Developing Countries (IDC) today, to a great extent, depend on Industrialized Countries (IC) for the supply of most industrial goods. An attempt has been made to ascertain the degree of design incompatibility experienced by users of these imported goods due to differences in the body sizes of people in producer and user countries. A comparative study of variations in body sizes is made from data available in literature and from anthropometric surveys. The results reveal differences in almost every part of the human body. The need for reliable anthropometric data in respect of IDC is stressed. Urgent measures are required to introduce changes in equipment, particularly for the benefit of users in IDC.

  • 93.
    Abeysekera, John D.A.
    et al.
    Tekniska högskolan i Luleå, CEDC.
    Shahnavaz, Houshang
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Effect of the hot environment on man1988In: International Symposium on Work in a Hot Environment and Heat Related Disorders, Khartoum 27-31 Jan. 1988, 1988Conference paper (Other academic)
  • 94.
    Abeysekera, John D.A
    et al.
    Tekniska högskolan i Luleå, CEDC.
    Shahnavaz, Houshang
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Ergonomic evaluation of modified industrial safety helmets for use in tropical environments1988In: Ergonomics International 88: proceedings of the tenth congress of the International Ergonomics Association, 1-5 August 1988, Sydney, Australia / [ed] Austen S. Adams, London: Taylor and Francis Group , 1988, p. 212-214Conference paper (Refereed)
  • 95.
    Abeysekera, John D.A.
    et al.
    Tekniska högskolan i Luleå, CEDC.
    Shahnavaz, Houshang
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Ergonomics aspects of personal protective equipment: its use in industrially developing countries1988In: Journal of Human Ergology, ISSN 0300-8134, Vol. 17, no 1, p. 67-79Article in journal (Refereed)
  • 96.
    Abeysekera, John D.A.
    et al.
    Tekniska högskolan i Luleå, CEDC.
    Shahnavaz, Houshang
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Ergonomics assessment of selected dust respirators: their use in the tropics1987In: Applied Ergonomics, ISSN 0003-6870, E-ISSN 1872-9126, Vol. 18, no 4, p. 266-72Article in journal (Refereed)
    Abstract [en]

    The suitability and effectiveness of four different types of British made respirators were studied with respect to comfort, convenience and fit on wearers in Sri Lanka (a developing country). Objective and subjective assessments were made to evaluate the degree of discomfort and interferences to the use of senses. The study revealed that factors such as breathing resistance, work-rate and activity period affected the physiological responses. The weight of the respirator and the skin temperature had no direct relationship with the cardiovascular stress. Positive-pressure respirators that gave lower face temperatures than negative-pressure masks gave this type of respirator an additional advantage in hot environments. Respirators that restricted jaw movement affected the speech intelligibility of the wearer. Orinasal masks restricted vision more than the other types. The problem of fit was found negligible though head and face dimensions significantly differed between the British and the Sri Lankans. Subjective assessment correlated well with objective tests.

  • 97.
    Abeysekera, John D.A.
    et al.
    Tekniska högskolan i Luleå, CEDC.
    Shahnavaz, Houshang
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Ergonomics evaluation of modified industrial helmets for use in tropical environments1988In: Ergonomics, ISSN 0014-0139, E-ISSN 1366-5847, Vol. 31, no 9, p. 1317-1329Article in journal (Refereed)
    Abstract [en]

    Hotness, weight, fitting problems etc., have been found to be the chief causes of the unpopularity of industrial safety helmets in tropical environments in developing countries (DC). Some selected safety helmets manufactured in industrialized countries (IC) were modified to provide extra head ventilation and to reduce weight, in order to make them more acceptable to users in hot environments. The modified helmets were subjected to ergonomics evaluation both objectively and subjectively in the laboratory (in simulated tropical conditions) as well as in the field situation. There was evidence that white helmets had some advantages in comfort, viz. reduction of hotness, compared to the other colours, e.g. red, green etc., when worn in the presence of radiant heat in the laboratory. Ventilation holes provided at the top of the shell seemed to reduce the greenhouse effect within the helmet shell which therefore felt less uncomfortable than a fully covered helmet. Even with a small reduction of weight, such as 45 g in helmets weighing about 350g, the difference in weight was perceived by the wearers. In adapting helmets made in IC for use in tropical climates, head ventilation and low weight perception are important aspects in comfort which need to be considered. In addition to low cost, a harness material suitable for sweat absorption is required. Adjustability and sizing to fit 90% of the user population also needs to be considered in the design and manufacture of safety helmets for people in DC.

  • 98. Abeysekera, John D.A.
    et al.
    Shahnavaz, Houshang
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Ergonomics of technology transfer1987In: International Journal of Industrial Ergonomics, ISSN 0169-8141, E-ISSN 1872-8219, Vol. 1, no 4, p. 265-272Article in journal (Refereed)
    Abstract [en]

    It is beyond doubt that high technology has elevated the standards of living of mankind. The modern technology created and developed to a great extent by Western or developed societies is now in great demand in Eastern and developing societies who are trying to leap-frog towards advancement. But unfortunately, in the transfer of technology, both the giver and the receiver seem to make many mistakes. A technology transferred without considering the ethnic variables in the societies and differences in the climates, has found to cause problems to the acquirer. Due to the basic human factor differences such as sizes of people, physical environment, physical capacities and organizational and cultural differences, a technology which is unadapted has found to be inappropriate, harmful, hazardous and unsuccessful. In the areas of health, working conditions, production and finance, undesirable effects have resulted through haphazard technology transfer, For a successful transfer, it is therefore stressed that technology has to be adapted or modified taking into consideration the technological, anthropological and socio-economic factors of the acquiring population

  • 99.
    Abeysekera, John D.A.
    et al.
    Tekniska högskolan i Luleå, CEDC.
    Shahnavaz, Houshang
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Ergonomics problems in the use of personal protective wear in industrially developing countries1987In: Proccedings of the XIth World congress on the prevention of occupational accidents and diseases: Stockholm, Sweden, 24-29 May 1987, 1987, p. 422-424Conference paper (Refereed)
  • 100.
    Abeysekera, John D.A.
    et al.
    Luleå tekniska universitet.
    Shahnavaz, Houshang
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Thermal environment and man1986Report (Other academic)
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