Pulling force prediction using neural networks

Purpose. In ergonomics and human factors investigations, pulling force (PF) estimation has usually been achieved using various types of biomechanical models, and independent approximation of PF was done with the help of upper extremity joints. Recently, multiple regression methods have gained importance for task-relevant inputs in predicting PF. Artificial neural networks (ANNs) also play a vital role in fitting the data; however, their use in work-related biomechanics and ergonomics is inadequate. Therefore, the current research aimed to accomplish comparative investigation of ANN and regression models by assessing their capacity to predict PF values. Methods. Multipositional PF data were acquired from 200 subjects at three different handle heights and body locations. ANN and regression models were formed using a random sample of three subsets (75% training, 15% selection, 10% validation) for proving the outcomes. Results. The comparison of ANN and regression models shows that the predictions of ANN models had a profoundly explained variance and lower root mean square difference values for the PF data at three handle heights. Conclusions. These outcomes advise that ANNs offer a precise and robust substitute for regression methods, and should be considered a useful method in biomechanics and ergonomics task assessments.     

EFFECT OF WATERSHED SUBDIVISION ON SWAT FLOW,SEDIMENT, AND NUTRIENT PREDICTIONS1

ABSTRACT: The size, scale, and number of subwatersheds can affect a watershed modeling process and subsequent results. The objective of this study was to determine the appropriate level of subwatershed division for simulating flow, sediment, and nutrients over 30 years for four Iowa watersheds ranging in size from 2,000 to 18,000 km² with the Soil and Water Assessment Tool (SWAT) model. The results of the analysis indicated that variation in the total number of subwatersheds had very little effect on streamflow. However, the opposite result was found for sediment, nitrate, and inorganic P; the optimal threshold subwatershed sizes, relative to the total drainage area for each watershed, required to adequately predict these three indicators were found to be around 3, 2, and 5 percent, respectively. Decreasing the size of the subwatersheds below these threshold levels does not significantly affect the predicted levels of these environmental indicators. These threshold subwatershed sizes can be used to optimize input data preparation requirements for SWAT analyses of other watersheds, especially those within a similar size range. The fact that different thresholds emerged for the different indicators also indicates the need for SWAT users to assess which indicators should have the highest priority in their analyses.     

UV-irradiation assisted functionalization and binding of Pd nanoparticles in polycarbonate membranes for hydrogen separation

Environmental Science and Pollution Research - For hydrogen-based energy systems development, purified hydrogen (H2) is a basic requirement and it can be achieved by using the H2-selective...     

Microbial and size characterization of airborne particulate matter collected on sticky tapes along US–Mexico border

Particulate matter(PM) emissions from various sources can affect significantly human health and environmental quality especially in the Chihuahuan Desert region along US–Mexico border. The objective of this study was to use the low-cost sticky tape method to collect airborne PM for size characterization and identification of fungal spores. Sticky tape samplers were placed at 1.0 and 2.0 m above the ground surface at experimental sites in Ciudad Juárez, Mexico and at 0.6, 1.2 and 1.8 m at New Mexico sites, USA. Soil samples were collected in both countries to determine fungal diversity, texture and moisture content Dust particles collected from all of the experimental sites had a dominant texture of clay( 0.002 mm). The dominant textures identified from soil samples collected from the US and Mexican sites were loam and sandy clay loam, respectively. Alternaria, Penicillium and Fusarium were frequently found funguses in the US sites while Alternaria and Aspergillus were commonly observed in the Mexican sites. The sticky tapes also showed a similar diversity of fungal microorganisms present in the airborne PM at both Mexico and US sites Alternaria, Penicillium and Aspergillus were the three groups of airborne fungal microorganisms consistently present in the US and Mexican sites. The low-cost sticky tape method has the potential to be used for characterizing different airborne microorganisms and dust particles.     

Occurrence,toxicity and remediation of polyethylene terephthalate plastics. A review

Environmental Chemistry Letters - Polyethylene terephthalate is a common plastic in many products such as viscose rayon for clothing, and packaging material in the food and beverage industries....     

Wild fruits as a contribution to sustainable rural development: a case study from the Garhwal Himalaya

Garhwal Himalaya is an important source of wild fruit species. These wild fruit trees grow abundantly across an altitudinal gradient of Himalaya and the majority of them bear fruits during summer. Fruit varieties are eaten raw by the local inhabitants of the region and whilst they are a rich source of protein, carbohydrate, fat and other elements, compared to cultivated fruits, they have not yet been considered as a source of alternative food products. About 13 potentially exploitable species of wild fruits and one semi-domesticated species having high potential for exploitation were selected for study; six (Aegle marmelos, Berberis asiatica, Hippophae rhamnoides, Myrica nagi, Rubus ellipticus and Prunus armeniaca) were examined in detail for their economic potential. Among the wild fruits, Hippophae rhamnoides was found to be economically efficient, followed by Aegle marmelos, Rubus ellipticus and Myrica nagi, respectively. Prunus armeniaca, a semi-domesticated and less utilized fruit of the higher Himalaya, provides better economic returns on an annual basis. The authors have recently made an attempt to utilize these wild fruits as a source of income, particularly for poor rural inhabitants and unemployed youths of the region by making a variety of edible products such as jam, jelly, juice, squash, sauce, etc. The enterprise was demonstrated to the people to encourage them to adopt it in the form of a small village-level cottage industry. The present paper discusses the distribution, botany, phenology, yield, ethnobotany, and uses of these species, and the cost-benefit analysis of food products prepared from them.     

Nerve conduction studies in sprayers occupationally exposed to mixture of pesticides in a mango plantation at Lucknow,North India

In this study, nerve conduction, organochlorine (OC) pesticide residues in blood and cholinesterase activity levels of pesticide sprayers employed in mango plantations at Lucknow, North India, were determined. Fifty-two sprayers from mango plantations who regularly spray mixture of pesticides like organophosphates (OP), OCs, and carbamates were considered as exposed group. Eighteen subjects with similar socio-economic status of exposed group, who do not handle pesticides, were selected as controls. Questionnaire-based interviews related to personal and occupational histories of the study subjects were carried out. Sprayers did not use any personal protective equipment during pesticide handling. The blood-pesticide analyses of sprayers show higher mean values of hexachlorohexane (HCH), γ-HCH, δ-HCH, total HCH, op-DDT compared with the controls. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activites were significantly reduced among sprayers. Risk of motor nerve conduction deficits was observed in sprayers with low AChE activity. Negative correlation of motor and sensory nerve conduction deficits was observed with the duration of exposure and age among sprayers. The study demonstrated that the prolonged exposure to mixture of pesticides, ergonomic factors, decline in cholinesterase activity may lead to nerve conduction dysfunction. The findings suggest the need for controlled use of pesticides in the plantation and indicated the need for training and implementation of hygiene practices like proper usage of personal protective equipments.     

Non-powered hand tool improvement research for prevention of work-related problems: a review

Purpose. In lower-middle-income countries, most of the work is performed manually using non-ergonomic hand tools which results in work-related health problems. Using hand tools designed in line with ergonomic principles may play an important role in reducing work-related health concerns significantly. Methods. Scientific databases (PubMed, EBSCOhost) and e-publishers were searched for articles from 1985 to 2015 using the following keywords: ‘hand tool’, ‘ergonomics’, ‘usability’ and ‘design’. After applying selection criteria to 614 articles, 58 articles related to the physical design of hand tools were selected. Results. Seventeen articles were related to hand tool improvement in the manufacturing sector. Musculoskeletal disorders were found to be the most frequently occurring work-related health problems. Most of the articles focused on product and qualitative variables for improvement in hand tools, while few articles considered human and task variables. Conclusions. Literature shows that hand tool improvement studies have been given less importance in low-income and lower-middle-income countries. However, some work of significance is reported in the agriculture sectors of these countries. Hence, it is concluded that ergonomic intervention in hand tools is much needed for those industries which employ traditional methods of working.