| 1. |
- Abbas, Syed Sohail, et al.
(författare)
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Compact Er 3+-doped ZBLAN green upconversion fibre laser
- 2011
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Ingår i: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 78, s. 756-758
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, a fibre laser at 546 nm has been studied for a signal power of -30 dB. Er 3+-doped ZBLAN fibre has been used by upconversion pumping of a 980 nm laser diode. Gain saturation effect has been investigated in detail. Laser performance has also been discussed. An efficiency of 35% has been calculated with a length of 5 mm fibre laser. Results show that Er 3+-doped ZBLAN is a promising candidate for optical amplification at 546 nm.
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| 2. |
- Ahmad, Azeem, et al.
(författare)
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Limitations of the analytic hierarchy process technique with respect to geographically distributed stakeholders
- 2010
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Ingår i: Proceedings of World Academy of Science, Engineering and Technology. - : World Academy of Science. - 2010-376X .- 2070-3740. ; 70:Sept., s. 111-116
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Tidskriftsartikel (refereegranskat)abstract
- The selection of appropriate requirements for product releases can make a big difference in a product success. The selection of requirements is done by different requirements prioritization techniques. These techniques are based on pre-defined and systematic steps to calculate the requirements relative weight. Prioritization is complicated by new development settings, shifting from traditional co-located development to geographically distributed development. Stakeholders, connected to a project, are distributed all over the world. These geographically distributions of stakeholders make it hard to prioritize requirements as each stakeholder have their own perception and expectations of the requirements in a software project. This paper discusses limitations of the Analytical Hierarchy Process with respect to geographically distributed stakeholders' (GDS) prioritization of requirements. This paper also provides a solution, in the form of a modified AHP, in order to prioritize requirements for GDS. We will conduct two experiments in this paper and will analyze the results in order to discuss AHP limitations with respect to GDS. The modified AHP variant is also validated in this paper.
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| 3. |
- Ahmadzadeh, Farzaneh
(författare)
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Diagnosing the Cause and Its Timing of Changes in Multivariate Process Mean Vector From Quality Control Charts Using Artificial Neural Network
- 2011
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Ingår i: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 78, s. 212-217
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Tidskriftsartikel (refereegranskat)abstract
- Quality control charts are very effective in detecting out of control signals but when a control chart signals an out of control condition of the process mean, searching for a special cause in the vicinity of the signal time would not always lead to prompt identification of the source(s) of the out of control condition as the change point in the process parameter(s) is usually different from the signal time. It is very important to manufacturer to determine at what point and which parameters in the past caused the signal. Early warning of process change would expedite the search for the special causes and enhance quality at lower cost. In this paper the quality variables under investigation are assumed to follow a multivariate normal distribution with known means and variance-covariance matrix and the process means after one step change remain at the new level until the special cause is being identified and removed, also it is supposed that only one variable could be changed at the same time. This research applies artificial neural network (ANN) to identify the time the change occurred and the parameter which caused the change or shift. The performance of the approach was assessed through a computer simulation experiment. The results show that neural network performs effectively and equally well for the whole shift magnitude which has been considered.
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| 4. |
- Ahmed, Hesham, et al.
(författare)
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Energy Efficient Recycling of in-Plant Fines
- 2014
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Ingår i: Proceedings of World Academy of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 8:6, s. 485-491
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Tidskriftsartikel (refereegranskat)abstract
- Numerous amounts of metallurgical dusts and sludge containing iron as well as some other valuable elements such as Zn, Pb and C are annually produced in the steelmaking industry. These alternative iron ore resources (fines) with unsatisfying physical and metallurgical properties are difficult to recycle. However, agglomerating these fines to be further used as a feed stock for existing iron and steelmaking processes is practiced successfully at several plants but for limited extent.In the present study, briquettes of integrated steelmaking industry waste materials (namely, BF-dust and sludge, BOF-dust and sludge) were used as feed stock to produce direct reduced iron (DRI). Physical and metallurgical properties of produced briquettes were investigated by means of TGA/DTA/QMS in combination with XRD. Swelling, softening and melting behavior were also studied using heating microscope.
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| 5. |
- Barbero-López, Aitor, et al.
(författare)
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Analysis of Green Wood Preservation Chemicals
- 2018
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Ingår i: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 12:3, s. 175-181
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Tidskriftsartikel (refereegranskat)abstract
- Wood decay is addressed continuously within thewood industry through use and development of wood preservatives.The increasing awareness on the negative effects of many chemicalstowards the environment is causing political restrictions in their useand creating more urgent need for research on green alternatives.This paper discusses some of the possible natural extracts for woodpreserving applications and compares the analytical methodsavailable for testing their behavior and efficiency against decayfungi. The results indicate that natural extracts have interestingchemical constituents that delay fungal growth but vary in efficiencydepending on the chemical concentration and substrate used. Resultsalso suggest that presence and redistribution of preservatives in woodduring exposure trials can be assessed by spectral imaging methodsalthough standardized methods are not available. This studyconcludes that, in addition to the many standard methods available,there is a need to develop new faster methods for screening potentialpreservative formulation while maintaining the comparability andrelevance of results.
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| 6. |
- Bodell, Victor, et al.
(författare)
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Comparing Machine Learning Estimation of Fuel Consumption of Heavy-Duty Vehicles
- 2021
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Ingår i: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 15:2, s. 97-101
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Tidskriftsartikel (refereegranskat)abstract
- Fuel consumption (FC) is one of the key factors indetermining expenses of operating a heavy-duty vehicle. A customermay therefore request an estimate of the FC of a desired vehicle.The modular design of heavy-duty vehicles allows their constructionby specifying the building blocks, such as gear box, engine andchassis type. If the combination of building blocks is unprecedented,it is unfeasible to measure the FC, since this would first r equire theconstruction of the vehicle. This paper proposes a machine learningapproach to predict FC. This study uses around 40,000 vehiclesspecific a nd o perational e nvironmental c onditions i nformation, suchas road slopes and driver profiles. A ll v ehicles h ave d iesel enginesand a mileage of more than 20,000 km. The data is used to investigatethe accuracy of machine learning algorithms Linear regression (LR),K-nearest neighbor (KNN) and Artificial n eural n etworks ( ANN) inpredicting fuel consumption for heavy-duty vehicles. Performance ofthe algorithms is evaluated by reporting the prediction error on bothsimulated data and operational measurements. The performance of thealgorithms is compared using nested cross-validation and statisticalhypothesis testing. The statistical evaluation procedure finds thatANNs have the lowest prediction error compared to LR and KNNin estimating fuel consumption on both simulated and operationaldata. The models have a mean relative prediction error of 0.3% onsimulated data, and 4.2% on operational data.
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| 7. |
- Cheng, Xin, 1974-, et al.
(författare)
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Hardware Centric Machine Vision for High Precision Center of Gravity Calculation
- 2010
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Ingår i: PROCEEDINGS OF WORLD ACADEMY OF SCIENCE, ENGINEERING AND TECHNOLOGY. ; 40, s. 576-583
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Konferensbidrag (refereegranskat)abstract
- We present a hardware oriented method for real-time measurements of object’s position in video. The targeted application area is light spots used as references for robotic navigation. Different algorithms for dynamic thresholding are explored in combination with component labeling and Center Of Gravity (COG) for highest possible precision versus Signal-to-Noise Ratio (SNR). This method was developed with a low hardware cost in focus having only one convolution operation required for preprocessing of data.
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| 8. |
- Dobslaw, Felix, 1983-
(författare)
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A Parameter Tuning Framework for Metaheuristics Based on Design of Experiments and Artificial Neural Networks
- 2010
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Ingår i: Proceeding of the International Conference on Computer Mathematics and Natural Computing 2010. - : WASET. ; 64, s. 213-216
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Konferensbidrag (refereegranskat)abstract
- In this paper, a framework for the simplification andstandardization of metaheuristic related parameter tuning by applyinga four phase methodology, utilizing Design of Experiments andArtificial Neural Networks, is presented. Metaheuristics are multipurposeproblem solvers that are utilized on computational optimizationproblems for which no efficient problem-specific algorithmexists. Their successful application to concrete problems requires thefinding of a good initial parameter setting, which is a tedious andtime-consuming task. Recent research reveals the lack of approachwhen it comes to this so called parameter tuning process. In themajority of publications, researchers do have a weak motivation fortheir respective choices, if any. Because initial parameter settingshave a significant impact on the solutions quality, this course ofaction could lead to suboptimal experimental results, and therebya fraudulent basis for the drawing of conclusions.
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| 9. |
- Gåsvaer, Daniel, et al.
(författare)
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Kaikaku – Radical Improvement in Production
- 2012
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Ingår i: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 6:9, s. 1914-1921
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Tidskriftsartikel (refereegranskat)abstract
- Considering today’s increasing speed of change,radical and innovative improvement - Kaikaku, is a necessity parallelto continuous incremental improvement - Kaizen, especially forSME’s in order to attain the competitive edge needed to be profitable.During 2011, a qualitative single case study with the objective ofrealizing a kaikaku in production has been conducted. The case studywas run as a one year project using a collaborative approachincluding both researchers and company representatives. The casestudy was conducted with the purpose of gaining further knowledgeabout kaikaku realization as well as its implications. The empiricalresults provide insights about the great productivity results achievedby applying a specific kaikaku realization approach. However, it alsosheds light on the difficulty and contradiction of combininginnovation management and production system development.
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| 10. |
- Hallberg, David
(författare)
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Socioculture and cognitivist perspectives on language and communication barriers in learning
- 2009
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Ingår i: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 36:3(12), s. 172-181
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Tidskriftsartikel (refereegranskat)abstract
- It is believed that major account on language diversity must be taken in learning, and especially in learning using ICT. This paper's objective is to exhibit language and communication barriers in learning, to approach the topic from socioculture and cognitivist perspectives, and to give exploratory solutions of handling such barriers. The review is mainly conducted by approaching the journal Computers & Education, but also an initially broad search was conducted. The results show that not much attention is paid on language and communication barriers in an immediate relation to learning using ICT. The results shows, inter alia, that language and communication barriers are caused because of not enough account is taken on both the individual's background and the technology.
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| 11. |
- Hansson, Karin, et al.
(författare)
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Diversity and Public Decision Making
- 2012
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Ingår i: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology. - : World Academy of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; :0071, s. 1678-1683, s. 1678-1683
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Tidskriftsartikel (refereegranskat)abstract
- Within the realm of e-government, the development has moved towards testing new means for democratic decision-making, like e-panels, electronic discussion forums, and polls. Although such new developments seem promising, they are not problem-free, and the outcomes are seldom used in the subsequent formal political procedures. Nevertheless, process models offer promising potential when it comes to structuring and supporting transparency of decision processes in order to facilitate the integration of the public into decision-making procedures in a reasonable and manageable way. Based on real-life cases of urban planning processes in Sweden, we present an outline for an integrated framework for public decision making to: a) provide tools for citizens to organize discussion and create opinions; b) enable governments, authorities, and institutions to better analyse these opinions; and c) enable governments to account for this information in planning and societal decision making by employing a process model for structured public decision making.
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| 12. |
- Hatem, Mohammed, et al.
(författare)
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Packing theory for natural and crushed aggregate to obtain the best mix of aggregate : research and development
- 2012
-
Ingår i: Proceedings of World Academy of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 6:7, s. 479-485
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Tidskriftsartikel (refereegranskat)abstract
- Concrete performance is strongly affected by the particle packing degree since it determines the distribution of the cementitious component and the interaction of mineral particles. By using packing theory designers will be able to select optimal aggregate materials for preparing concrete with low cement content, which is beneficial from the point of cost. Optimum particle packing implies minimizing porosity and thereby reducing the amount of cement paste needed to fill the voids between the aggregate particles, taking also the rheology of the concrete into consideration. For reaching good fluidity superplasticizers are required. The results from pilot tests at Luleå University of Technology (LTU) show various forms of the proposed theoretical models, and the empirical approach taken in the study seems to provide a safer basis for developing new, improved packing models.
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| 13. |
- Hölttä, V., et al.
(författare)
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Lean information management model for engineering changes
- 2010
-
Ingår i: Proceedings of World Academy of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 42, s. 1459-1466
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Tidskriftsartikel (refereegranskat)abstract
- Poor engineering change management (ECM) can cause slow and uncontrollable product development projects. Engineering changes (ECs) create a need for efficient information exchange between the companies in the supply chain. Four case studies were conducted in the heavy machinery, mechatronics, and automotive industries to identify the current challenges in ECM. A comparison between the challenges of ECM and the principles of lean product development (LPD) indicates that fulfilling these principles will generate a better ECM process. The LPD principles were applied to information management to create a model for lean information management (LIM). The purpose of this model is to make ECM more efficient. The initial results of these implementations suggest that the lead times of information transfer can be reduced using this approach. The LIM principles presented in our model will address most of the challenges in ECM.
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| 14. |
- Kalinina, Maria, et al.
(författare)
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Easy-Interactive Ordering of the Pareto Optimal Set with Imprecise Weights
- 2013
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Ingår i: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 7:4, s. 504-509
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Tidskriftsartikel (refereegranskat)abstract
- In the multi objective optimization, in the case when generated set of Pareto optimal solutions is large, occurs the problem to select of the best solution from this set. In this paper, is suggested a method to order of Pareto set. Ordering the Pareto optimal set carried out in conformity with the introduced distance function between each solution and selected reference point, where the reference point may be adjusted to represent the preferences of a decision making agent. Preference information about objective weights from a decision maker may be expressed imprecisely. The developed elicitation procedure provides an opportunity to obtain surrogate numerical weights for the objectives, and thus, to manage impreciseness of preference. The proposed method is a scalable to many objectives and can be used independently or as complementary to the various visualization techniques in the multidimensional case.
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| 15. |
- Karunaratne, Thashmee, 1968-, et al.
(författare)
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DIFFER: A Propositionalization Approach for Learning from Structured Data
- 2006
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Ingår i: Proceedings of World Academy of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 15, s. 49-51
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Tidskriftsartikel (refereegranskat)abstract
- Logic based methods for learning from structured data is limited w.r.t. handling large search spaces, preventing large-sized substructures from being considered by the resulting classifiers. A novel approach to learning from structured data is introduced that employs a structure transformation method, called finger printing, for addressing these limitations. The method, which generates features corresponding to arbitrarily complex substructures, is implemented in a system, called DIFFER. The method is demonstrated to perform comparably to an existing state-of-art method on some benchmark data sets without requiring restrictions on the search space. Furthermore, learning from the union of features generated by finger printing and the previous method outperforms learning from each individual set of features on all benchmark data sets, demonstrating the benefit of developing complementary, rather than competing, methods for structure classification.
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| 16. |
- Otine, Charles, et al.
(författare)
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Dimensional modeling of HIV data using open source
- 2010
-
Ingår i: Proceedings of World Academy of Science, Engineering and Technology. - : World Academy of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 62:March, s. 156-161
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Tidskriftsartikel (refereegranskat)abstract
- Selecting the data modeling technique for an information system is determined by the objective of the resultant data model. Dimensional modeling is the preferred modeling technique for data destined for data warehouses and data mining, presenting data models that ease analysis and queries which are in contrast with entity relationship modeling. The establishment of data warehouses as components of information system landscapes in many organizations has subsequently led to the development of dimensional modeling. This has been significantly more developed and reported for the commercial database management systems as compared to the open sources thereby making it less affordable for those in resource constrained settings. This paper presents dimensional modeling of HIV patient information using open source modeling tools. It aims to take advantage of the fact that the most affected regions by the HIV virus are also heavily resource constrained (sub-Saharan Africa) whereas having large quantities of HIV data. Two HIV data source systems were studied to identify appropriate dimensions and facts these were then modeled using two open source dimensional modeling tools. Use of open source would reduce the software costs for dimensional modeling and in turn make data warehousing and data mining more feasible even for those in resource constrained settings but with data available.
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| 17. |
- Rizvi, S. M. Sarwarul Islam, et al.
(författare)
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Security of mobile agent in ad hoc network using threshold cryptography
- 2010
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Ingår i: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 46, s. 1039-1042
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Tidskriftsartikel (refereegranskat)abstract
- In a very simple form a Mobile Agent is an independent piece of code that has mobility and autonomy behavior. One of the main advantages of using Mobile Agent in a network is - it reduces network traffic load. In an, ad hoc network Mobile Agent can be used to protect the network by using agent based IDS or IPS. Besides, to deploy dynamic software in the network or to retrieve information from network nodes Mobile Agent can be useful. But in an ad hoc network the Mobile Agent itself needs some security. Security services should be guaranteed both for Mobile Agent and for Agent Server. In this paper to protect the Mobile Agent and Agent Server in an ad hoc network we have proposed a solution which is based on Threshold Cryptography, a new vibe in the cryptographic world where trust is distributed among multiple nodes in the network.
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| 18. |
- Sackey, Jocelyn, et al.
(författare)
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Relational impact of job stress on gender based managerial effectiveness in Ghanaian organizations
- 2011
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Ingår i: Proceedings of World Academy of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; :60, s. 2074-2083
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Tidskriftsartikel (refereegranskat)abstract
- This study explored the relationship between occupational stress and the perceived effectiveness of men and women managers in Ghanaian organizations. The exploration is underlined by attempt to understand the degree to which male and female managers in Ghanaian organizations experience occupational stress at the workplace. The purpose is to examine the sources and extents of occupational stress experienced by male and female managers in Ghana. Data was collected using questionnaires and analyzed using both descriptive statistics and correlation analysis. The results showed that female managers in Ghana are more likely to report of more stress experiences in the workplace than their male counterparts. The female managers are more likely to perceive role conflict and alienation as job stressors while the male managers perceived blocked career as a major source of workplace stress. It is concluded that despite the female managers experiencing enormous level of occupational stress, there was no significant differences between their managerial effectiveness and that of the male.
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| 19. |
- Saleem, Jawad, 1975-, et al.
(författare)
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Nugget Formation During Resistance Spot Welding Using Finite Element Model
- 2012
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Ingår i: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 67
-
Tidskriftsartikel (refereegranskat)abstract
- Resistance spot welding process comprises of electric, thermal and mechanical phenomenon, which makes this process complex and highly non-linear and thus, it becomes difficult to model it. In order to obtain good weld nugget during spot welding, hit and trial welds are usually done which is very costly. Therefore the numerical simulation research has been conducted to understand the whole process. In this paper three different cases were analyzed by varying the tip contact area and it was observed that, with the variation of tip contact area the nugget formation at the faying surface is affected. The tip contact area of the welding electrode becomes large with long welding cycles. Therefore in order to maintain consistency of nugget formation during the welding process, the current compensation in control feedback is required. If the contact area of the welding electrode tip is reduced, a large amount of current flows through the faying surface, as a result of which sputtering occurs.
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| 20. |
- Sanda, Mohammed-Aminu, et al.
(författare)
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Conceptualization of the attractive work environment and organizational activity for humans in future deep mines
- 2011
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Ingår i: International Journal of Human and Social Sciences. - 1307-8046. ; 5:2, s. 256-262
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this paper is to conceptualize a future-oriented human work environment and organizational activity in deep mines that entails a vision of good and safe workplace. Future-oriented technological challenges and mental images required for modern work organization design were appraised. It is argued that an intelligent-deep-mine covering the entire value chain, including environmental issues and with work organization that supports good working and social conditions towards increased human productivity could be designed. With such intelligent system and work organization in place, the mining industry could be seen as a place where cooperation, skills development and gender equality are key components. By this perspective, both the youth and women might view mining activity as an attractive job and the work environment as a safe, and this could go a long way in breaking the unequal gender balance that exists in most mines today.
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| 21. |
- Sangiorgio, Filippo, et al.
(författare)
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Resistance and Sub-Resistances of RC Beams Subjected to Multiple Failure Modes
- 2015
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Ingår i: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 9:2, s. 145-153
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Tidskriftsartikel (refereegranskat)abstract
- Geometric and mechanical properties all influence the resistance of RC structures and may, in certain combination of property values, increase the risk of a brittle failure of the whole system.This paper presents a statistical and probabilistic investigation on the resistance of RC beams designed according to Eurocodes 2 and 8, and subjected to multiple failure modes, under both the natural variation of material properties and the uncertainty associated with cross-section and transverse reinforcement geometry. A full probabilistic model based on JCSS Probabilistic Model Code is derived. Different beams are studied through material nonlinear analysis via Monte Carlo simulations. The resistance model is consistent with Eurocode 2. Both a multivariate statistical evaluation and the data clustering analysis of outcomes are then performed.Results show that the ultimate load behaviour of RC beams subjected to flexural and shear failure modes seems to be mainly influenced by the combination of the mechanical properties of both longitudinal reinforcement and stirrups, and the tensile strength of concrete, of which the latter appears to affect the overall response of the system in a nonlinear way. The model uncertainty of the resistance model used in the analysis plays undoubtedly an important role in interpreting results.
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| 22. |
- Soria-Salinas, Álvaro, et al.
(författare)
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A Xenon Mass Gauging through Heat Transfer Modeling for Electric Propulsion Thrusters
- 2017
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Ingår i: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology. - : World Academy of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 11:1, s. 94-105
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Tidskriftsartikel (refereegranskat)abstract
- The current state-of-the-art methods of mass gauging of Electric Propulsion (EP) propellants in microgravity conditions rely on external measurements that are taken at the surface of the tank. The tanks are operated under a constant thermal duty cycle to store the propellant within a pre-defined temperature and pressure range. We demonstrate using computational fluid dynamics (CFD) simulations that the heat-transfer within the pressurized propellant generates temperature and density anisotropies. This challenges the standard mass gauging methods that rely on the use of time changing skin-temperatures and pressures. We observe that the domes of the tanks are prone to be overheated, and that a long time after the heaters of the thermal cycle are switched off, the system reaches a quasi-equilibrium state with a more uniform density. We propose a new gauging method, which we call the Improved PVT method, based on universal physics and thermodynamics principles, existing TRL-9 technology and telemetry data. This method only uses as inputs the temperature and pressure readings of sensors externally attached to the tank. These sensors can operate during the nominal thermal duty cycle. The improved PVT method shows little sensitivity to the pressure sensor drifts which are critical towards the end-of-life of the missions, as well as little sensitivity to systematic temperature errors. The retrieval method has been validated experimentally with CO2 in gas and fluid state in a chamber that operates up to 82 bar within a nominal thermal cycle of 38 °C to 42 °C. The mass gauging error is shown to be lower than 1% the mass at the beginning of life, assuming an initial tank load at 100 bar. In particular, for a pressure of about 70 bar, just below the critical pressure of CO2, the error of the mass gauging in gas phase goes down to 0.1% and for 77 bar, just above the critical point, the error of the mass gauging of the liquid phase is 0.6% of initial tank load. This gauging method improves by a factor of 8 the accuracy of the standard PVT retrievals using look-up tables with tabulated data from the National Institute of Standards and Technology.
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| 23. |
- Tripney, Rachel, et al.
(författare)
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Critical Psychosocial Risk Treatment for Engineers and Technicians
- 2019
-
Ingår i: World Academy of Science, Engineering and Technology: An International Journal of Science, Engineering and Technology. - 2010-376X .- 2070-3740. ; 13:8, s. 1070-1083
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Tidskriftsartikel (refereegranskat)abstract
- This study explores how management addresses psychosocial risks in seven teams of engineers and technicians in the midst of the fourth industrial revolution. The sample is from an ongoing quasi-experiment about psychosocial risk management in a manufacturing company in Sweden. Each of the seven teams belongs to one of two clusters: a positive cluster or a negative cluster. The positive cluster reports a significantly positive change in psychosocial risk levels between two time-points and the negative cluster reports a significantly negative change. The data are collected using semi-structured interviews. The results of the computer aided thematic analysis show that there are more differences than similarities when comparing the risk treatment actions taken between the two clusters. Findings show that the managers in the positive cluster use more enabling actions that foster and support formal and informal relationship building. In contrast, managers that use less enabling actions hinder the development of positive group processes and contribute negative changes in psychosocial risk levels. This exploratory study sheds some light on how management can influence significant positive and negative changes in psychosocial risk levels during a risk management process.
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| 24. |
- Abbas, Nahlah, et al.
(författare)
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Impacts of Climate Change on Water Resources of Greater Zab and Lesser Zab Basins, Iraq, Using Soil and Water Assessment Tool Model
- 2017
-
Ingår i: International Journal of Environmental, Chemical, Ecological, Geological and Geophysical Engineering. - : World Scientific and Engineering Academy and Society. - 2010-376X .- 2010-3778. ; 11:10, s. 823-829
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Tidskriftsartikel (refereegranskat)abstract
- The Greater Zab and Lesser Zab are the major tributaries of Tigris River contributing the largest flow volumes into the river. The impacts of climate change on water resources in these basins have not been well addressed. To gain a better understanding of the effects of climate change on water resources of the study area in near future (2049-2069) as well as in distant future (2080-2099), Soil and Water Assessment Tool (SWAT) was applied. The model was first calibrated for the period from 1979 to 2004 to test its suitability in describing the hydrological processes in the basins. The SWAT model showed a good performance in simulating streamflow. The calibrated model was then used to evaluate the impacts of climate change on water resources. Six general circulation models (GCMs) from phase five of the Coupled Model Intercomparison Project (CMIP5) under three Representative Concentration Pathways (RCPs) RCP 2.6, RCP 4.5, and RCP 8.5 for periods of 2049-2069 and 2080-2099 were used to project the climate change impacts on these basins. The results demonstrated a significant decline in water resources availability in the future.
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| 25. |
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| 26. |
- Lundgren, Lina, 1982-, et al.
(författare)
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Injuries related to kitesurfing
- 2011
-
Ingår i: World Academy of Science, Engineering and Technology. - Istanbul, Turkey : World Academy of Science, Engineering and Technology, WASET. - 2010-3778 .- 2010-376X. ; :77, s. 1132-1136
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Tidskriftsartikel (refereegranskat)abstract
- Participation in sporting activities can lead to injury. Sport injuries have been widely studied in many sports including the more extreme categories of aquatic board sports. Kitesurfing is a relatively new water surface action sport, and has not yet been widely studied in terms of injuries and stress on the body. The aim of this study was to get information about which injuries that are most common among kitesurfing practitioners, where they occur, and their causes. Injuries were studied using an international open web questionnaire (n=206). The results showed that many respondents reported injuries, in total 251 injuries to knee (24%), ankle (17%), trunk (16%) and shoulders (10%), often sustained while doing jumps and tricks (40%). Among the reported injuries were joint injuries (n=101), muscle/tendon damages (n=47), wounds and cuts (n=36) and bone fractures (n=28). Also environmental factors and equipment can influence the risk of injury, or the extent of injury in a hazardous situation. Conclusively, the information from this retrospective study supports earlier studies in terms of prevalence and site of injuries. Suggestively, this information should be used for to build a foundation of knowledge about the sport for development of applications for physical training and product development.
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| 27. |
- Saboori Shirazifard, Babak, 1981, et al.
(författare)
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Introducing fast robot roller hemming process in automotive industry
- 2009
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Ingår i: World Academy of Science, Engineering and Technology. - 2010-376X .- 2010-3778. ; 58, s. 503-506
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Tidskriftsartikel (refereegranskat)abstract
- As product life cycle becomes less and less every day, having flexible manufacturing processes for any companies seems more demanding. In the assembling of closures, i.e. opening parts in car body, hemming process is the one which needs more attention. This paper focused on the robot roller hemming process and how to reduce its cycle time by introducing a fast roller hemming process. A robot roller hemming process of a tailgate of Saab 93 SportCombi model is investigated as a case study in this paper. By applying task separation, robot coordination, and robot cell configuration principles in the roller hemming process, three alternatives are proposed, developed, and remarkable reduction in cycle times achieved [1].
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| 28. |
- Islam, Shafiqul, et al.
(författare)
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A Study of Shear Stress Intensity Factor of PP and HDPE by a Modified Experimental Method together with FEM
- 2013
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Ingår i: International Journal of Mechanical, Aerospace, Industrial and Mechatronics Engineering. - : WASET World Academy of Science, Engineering and Technology. - 2010-376X. ; 7:11
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Tidskriftsartikel (refereegranskat)abstract
- Shear testing is one of the most complex testing areas where available methods and specimen geometries are different from each other. Therefore, a modified shear test specimen (MSTS) combining the simple uniaxial test with a zone of interest (ZOI) is tested which gives almost the pure shear. In this study, material parameters of polypropylene (PP) and high density polyethylene (HDPE) are first measured by tensile tests with a dogbone shaped specimen. These parameters are then used as an input for the finite element analysis. Secondly, a specially designed specimen (MSTS) is used to perform the shear stress tests in a tensile testing machine to get the results in terms of forces and extension, crack initiation etc. Scanning Electron Microscopy (SEM) is also performed on the shear fracture surface to find material behavior. These experiments are then simulated by finite element method and compared with the experimental results in order to confirm the simulation model. Shear stress state is inspected to find the usability of the proposed shear specimen. Finally, a geometry correction factor can be established for these two materials in this specific loading and geometry with notch using Linear Elastic Fracture Mechanics (LEFM). By these results, strain energy of shear failure and stress intensity factor (SIF) of shear of these two polymers are discussed in the special application of the screw cap opening of the medical or food packages with a temper evidence safety solution.
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