| 1. |
- Ortiz Morales, Daniel, 1984-, et al.
(författare)
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Path-constrained motion analysis : an algorithm to understand human performance on hydraulic manipulators
- 2015
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Ingår i: IEEE Transactions on Human-Machine Systems. - 2168-2291. ; 45:2, s. 187-199
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Tidskriftsartikel (refereegranskat)abstract
- We propose a novel method to analyze how human operators use hydraulic manipulators of heavy-duty equipment. The approach is novel in the sense that it applies knowledge of motion planning and optimization techniques used in robotics. As an example, we consider the case of operating a forestry crane. To that end, we use motion data that has been recorded during standard operation with the help of sensors and a data acquisition unit. The data backs up the notion that operators work by performing repeatable patterns observed in the trajectories of the manipulator's joints. We show how this nominal behavior is computed, and consequently this allow us to present the following: 1) an analytical procedure to analyze motions, 2) how to represent the "performance" of the operator in a 2D plot, 3) an example of how to use this information to suggest customized control settings, and 4) some complementary ideas needed for improving efficiency through automation.
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| 2. |
- Ortiz Morales, Daniel, 1984-, et al.
(författare)
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Increasing the level of automation in the forestry logging process with crane trajectory planning and control
- 2014
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Ingår i: Journal of Field Robotics. - : Wiley-Blackwell. - 1556-4959 .- 1556-4967. ; 31:3, s. 343-363
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Tidskriftsartikel (refereegranskat)abstract
- Working with forestry machines requires great amount of training to be sufficiently skilledto operate forestry cranes. In view of this, introducing automated motions, as those seenin robotic arms, is ambitioned by this industry for shortening the amount of training timeand make the work of the operator easier. Motivated by this fact, we have developedtwo experimental platforms for testing control systems and motion planning algorithms inreal-time. They correspond to a laboratory setup and a commercial version of a hydraulicmanipulator used in forwarder machines. The aim of this article is to present the results ofthis development by providing an overview of our trajectory planning algorithm and motioncontrol method, with a subsequent view of the experimental results. For motion control,we design feedback controllers that are able to track reference trajectories based on sensormeasurements. Likewise, we provide arguments to design controllers in open-loop for thecase of machines lacking of sensing devices. Relying on the tracking efficiency of thesecontrollers, we design time efficient reference trajectories of motions that correspond tologging tasks. To demonstrate performance, we provide an overview of an extensive testingdone on these machines.
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| 3. |
- Ringdahl, Ola, 1971-, et al.
(författare)
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Estimating wheel slip for a forest machine using RTK-DGPS
- 2012
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Ingår i: Journal of terramechanics. - : Elsevier BV. - 0022-4898 .- 1879-1204. ; 49:5, s. 271-279
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Tidskriftsartikel (refereegranskat)abstract
- Wheel slip may increase the risk for wheel rutting and tear up ground vegetation and superficial roots and thereby decreasing the bearing capacity of the ground, but also reducing the growth of nearby standing forest trees. With increased slip, more energy is consumed for making wheel ruts in the ground, with increased fuel consumption as a result. This paper proposes a novel method for measuring slip in an uneven forest terrain with an 8WD forestry machine. This is done by comparing the wheel velocity reported by the machine and velocity measured with an accurate DGPS system. Field tests with a forestry machine showed that slip could be calculated accurately with the suggested method. The tests showed that there was almost no slip on asphalt or gravel surfaces. In a forest environment, 10–15% slip was common. A future extension of the method enabling estimation of the slip of each wheel pair in the bogies is also suggested.
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| 4. |
- Ahmed, Mukhtar
(författare)
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Dynamic Modeling
- 2020
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Ingår i: Systems Modeling. - Singapore : Springer Singapore. - 9789811547270 ; , s. 111-150
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Bokkapitel (refereegranskat)abstract
- Dynamic modeling is a valuable technique used to understand different systems on a temporal basis. This approach resulted in a more practical, intuitive endeavor modeling. The main objective of this chapter is to elaborate on different modeling approaches with more emphasis on dynamic modeling. Firstly mathematical modeling was discussed and defined as the quantitative expression of the biological system from the lower hierarchy to the higher. It is a description of a system using mathematical concepts and language to facilitate the process of explanation of a system. The mathematical model can be further classified into static or dynamic, deterministic or stochastic, and continuous or discrete. A model that uses large numbers of theoretical information to predict what happens at one level by considering processes at lower levels of the system is known as mechanistic models. In this book chapter, we present a general description of modeling with a history of dynamic modeling from the eighteenth century to today. Furthermore, the application of dynamic process-based crop growth model in different fields of studies was discussed. Outcomes of the reviewed studies confirmed that process-based dynamic crop simulation models are valuable tools for the understanding of the system and giving options and solutions to the what-if questions under different sets of scenarios and managements.
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| 5. |
- Ahmed, Mukhtar
(författare)
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Systems Modeling
- 2020
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Ingår i: Systems Modeling. - Singapore : Springer Singapore. - 9789811547270 ; , s. 1-44
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Bokkapitel (refereegranskat)abstract
- The agricultural systems have complex interactions with the surrounding environment and soil, and better understanding is possible through computer application. The interactions between systems and environment are so complex that one cannot quantify their cumulative affects without application of latest computing tools. The solar radiations, temperature, photoperiod, humidity, and wind are some of the important environmental variables which interact with agricultural system. These variables should be considered with importance for understanding the agricultural system on scientific basis. The light required is for photosynthesis and photoperiod, humidity for determination of water loss, and wind to transfer water vapors and gases to and from plants. The model converts qualitative data into quantitative to give out quantitative predictions to the theories which can be compared very easily in the real world. There is rich future for systems modeling, and it can open new frontiers and helps in the agroecological transitions of agriculture. Plants and crops should be considered as holobionts (individual host and its microbial community). In system modeling, the environmental variables are linked to various physiological processes to predict the crop responses with a given set of environmental conditions. The increased ozone concentration in the environment also damages the crop, and these impacts should be considered during model development. Similarly, application of different models at different scales is presented which could help to understand the mechanisms in qualitative and quantitative way. Last but not least, the concept of digital agriculture and its linkage with modeling were elaborated. In general the chapter discusses in detail the type, methods of measurement along with mathematical representation, terminologies, and their impact on the various processes of the plants.
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| 6. |
- Bosona, Techane, et al.
(författare)
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The role of blockchain technology in promoting traceability systems in agri-food production and supply chains
- 2023
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Ingår i: Sensors. - 1424-8220 .- 1424-3210. ; 23
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Forskningsöversikt (refereegranskat)abstract
- Due to recurring food quality and safety issues, growing segments of consumers, especially in developed markets, and regulators in agri-food supply chains (AFSCs) require a fast and trustworthy system to retrieve necessary information on their food products. With the existing centralized traceability systems used in AFSCs, it is difficult to acquire full traceability information, and there are risks of information loss and data tampering. To address these challenges, research on the application of blockchain technology (BCT) for traceability systems in the agri-food sector is increasing, and startup companies have emerged in recent years. However, there have been only a limited number of reviews on the application of BCT in the agriculture sector, especially those that focus on the BCT-based traceability of agricultural goods. To bridge this knowledge gap, we reviewed 78 studies that integrated BCT into traceability systems in AFSCs and additional relevant papers, mapping out the main types of food traceability information. The findings indicated that the existing BCT-based traceability systems focus more on fruit and vegetables, meat, dairy, and milk. A BCT-based traceability system enables one to develop and implement a decentralized, immutable, transparent, and reliable system in which process automation facilitates the monitoring of real-time data and decision-making activities. We also mapped out the main traceability information, key information providers, and challenges and benefits of the BCT-based traceability systems in AFSCs. These helped to design, develop, and implement BCT-based traceability systems, which, in turn, will contribute to the transition to smart AFSC systems. This study comprehensively illustrated that implementing BCT-based traceability systems also has important, positive implications for improving AFSC management, e.g., reductions in food loss and food recall incidents and the achievement of the United Nations SDGs (1, 3, 5, 9, 12). This will contribute to existing knowledge and be useful for academicians, managers, and practitioners in AFSCs, as well as policymakers.
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| 7. |
- Eriksson, Ola, et al.
(författare)
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The Use of Decision Support Systems in Forest Management: Analysis of FORSYS Country Reports
- 2016
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Ingår i: Forests. - : MDPI AG. - 1999-4907. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- From 2009 to 2013, a group of more than 100 researchers from 26 countries, under a COST-Action project named FORSYS, worked on a review of the use of forest management decision support systems (FMDSS). Guided by a template, local researchers conducted assessments of FMDSS use in their countries; their results were documented in Country Reports. In this study, we have used the Country Reports to construct a summary of FMDSS use. For the purposes of our analysis, we conducted a two-round categorisation of the main themes to describe the most relevant aspects of FMDSS use. The material produced was used to generate quantitative summaries of (i) the types of problem where FMDSS are used, (ii) models and methods used to solve these problems, (iii) knowledge management techniques, and (iv) participatory planning techniques. Beyond this, a qualitative analysis identified and summarised the local researchers' primary concerns, recorded in the conclusions to the Country Reports; we designated these "lessons learned". Results from the quantitative analysis suggested that most of the participant countries were making use of latest generation FMDSS. A few did not have practical problems that justified the use of such technology or they were still at the beginning of the process of building models to solve their own forest problems.
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| 8. |
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| 9. |
- Luengo, Cris, et al.
(författare)
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Rapid prototyping of image analysis applications
- 2011
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Ingår i: Medical Image Processing: Techniques and Applications. - New York, NY : Springer New York. - 9781441997692 ; , s. 5-25
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 10. |
- Nilsson, Mats
(författare)
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From open data to open analyses - new opportunities for environmental applications?
- 2017
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Ingår i: Environments. - : MDPI AG. - 0711-6780 .- 2076-3298. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- In this study, we explore the potential of open and accessible data in combination with interactive cloud-processing capabilities for applications in environmental monitoring and policies. During the last few years, the amount of open Earth observation and open national data has increased substantially. In parallel, access to analysis capabilities for such data has improved. The search and extraction of data from larger Earth observations archives and the processing of larger amounts of data have hitherto been an obstacle for many potential users. With the availability of new cloud solutions such as Google Earth Engine, NASA Earth Exchange, or ESA Cloud Toolbox, accessing and processing of large datasets have become easier for a wider range of users. In this communication, we briefly summarize these recent trends and illustrate their potential by four application showcases from terrestrial and aquatic environmental monitoring. We accessed and processed data from US and European Earth observation satellite archives with Google Earth Engine. As a complement, we also used open Swedish national data and open source desktop tools. We hope that our positive user experiences can encourage other environmental data users to further explore the new opportunities for easy access to open data and cloud-based processing capabilities.
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