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Author

Ulf Bodin

Other affiliations: TeliaSonera
Bio: Ulf Bodin is an academic researcher from Luleå University of Technology. The author has contributed to research in topics: Computer science & Loader. The author has an hindex of 11, co-authored 54 publications receiving 514 citations. Previous affiliations of Ulf Bodin include TeliaSonera.


Papers
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Journal ArticleDOI
TL;DR: In this article, the authors provide a survey of different areas of research within the scope of the earth-moving operation and identify the knowledge gaps to give direction to future research in this field.

166 citations

Journal ArticleDOI
01 Jul 2000
TL;DR: This paper evaluates the active queue management mechanisms RED In and Out (RIO) and Weighted RED (WRED) in providing levels of drop precedence under different loads and proposes a new AQM mechanism, WRED with Thresholds (WRT).
Abstract: Current work in the IETF aims at providing service differentiation on the Internet. One proposal is to provide loss differentiation by assigning levels of drop procedence to IP packets. In this paper, we evaluate the active queue management (AQM) mechanisms RED In and Out (RIO) and Weighted RED (WRED) in providing levels of drop precedence under different loads. For low drop precedence traffic, FIO and WRED can be configured to offer sheltering (i.e., low drop precedence traffic is protected from losses caused by higher drop precedence traffic). However, if traffic control fails or is inaccurate, such configurations can cause starvation of traffic at high drop precedence levels. Configuring WRED to instead offer relative differentiation can eliminate the risk of starvation. However, WRED cannot, without reconfiguration, both offer sheltering when low drop precedence traffic is properly controlled and avoid starvation at overload of low drop precedence traffic. To achieve this, we propose a new AQM mechanism, WRED with Thresholds (WRT). The benefit of WRT is that, without reconfiguration, it offers sheltering when low drop precedence traffic is properly controlled and relative differentiation otherwise. We present simulations showing that WRT has these properties.

50 citations

Patent
14 Nov 2003
TL;DR: In this paper, a data network is characterized by a first group of Network Resource Managers, NRMs, (b-d)) is arranged to control the resources of the first network level and a second group of NRMs (e-g), e-g) is arranged for performing an address mapping between the first and second addressing schemes.
Abstract: The present invention relates to a data network, method and a computer program product, wherein the data network is implemented by a first network level (104) having a first addressing scheme and at least a second network level (108) having a second addressing scheme. Each network level provides connectivity over at least one network domain. The data network is characterised in that a first group of Network Resource Managers, NRMs, (b-d)) is arranged to control the resources of the first network level and a second group of NRMs (e-g) is arranged to control the resources of the second network level. The NRMs of the first group (b-d) and second group (e-g) comprise means for exchanging resource requests by using the first addressing scheme and the NRMs (e-g) of the second group further comprise means for performing an address mapping between the first and second addressing schemes.

40 citations

Journal ArticleDOI
TL;DR: In this paper, a small time-delayed neural network (TDNN) is implemented in the bucket control-loop of a Volvo L180H front-end loader filling medium coarse gravel.

40 citations

Journal ArticleDOI
10 Dec 2020
TL;DR: A high-level IIoT architecture suitable for the mining industry is synthesized and presented, addressing the identified challenges and enabling smart mines by automation, interoperable systems, data distribution, and real-time visibility of the mining status.
Abstract: The Industrial Internet of Things (IIoT) has the potential to improve the production and business processes by enabling the extraction of valuable information from industrial processes. The mining industry, however, is rather traditional and somewhat slow to change due to infrastructural limitations in communication, data management, storage, and exchange of information. Most research efforts so far on applying IIoT in the mining industry focus on specific concerns such as ventilation monitoring, accident analysis, fleet and personnel management, tailing dam monitoring, and pre-alarm system while an overall IIoT architecture suitable for the general conditions in the mining industry is still missing. This article analyzes the current state of Information Technology in the mining sector and identifies a major challenge of vertical fragmentation due to the technological variety of various systems and devices offered by different vendors, preventing interoperability, data distribution, and the exchange of information securely between devices and systems. Based on guidelines and practices from the major IIoT standards, a high-level IIoT architecture suitable for the mining industry is then synthesized and presented, addressing the identified challenges and enabling smart mines by automation, interoperable systems, data distribution, and real-time visibility of the mining status. Remote controlling, data processing, and interoperability techniques of the architecture evolve all stages of mining from prospecting to reclamation. The adoption of such IIoT architecture in the mining industry offers safer mine site for workers, predictable mining operations, interoperable environment for both traditional and modern systems and devices, automation to reduce human intervention, and enables underground surveillance by converging operational technology (OT) and information technology (IT). Significant open research challenges and directions are also studied and identified in this paper, such as mobility management, scalability, virtualization at the IIoT edge, and digital twins.

36 citations


Cited by
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Journal ArticleDOI
TL;DR: A definition for cross-layer design is suggested, the basic types of cross- layer design with examples drawn from the literature are discussed, and the initial proposals on howcross-layer interactions may be implemented are categorized.
Abstract: Of late, there has been an avalanche of cross-layer design proposals for wireless networks. A number of researchers have looked at specific aspects of network performance and, approaching cross-layer design via their interpretation of what it implies, have presented several cross-layer design proposals. These proposals involve different layers of the protocol stack, and address both cellular and ad hoc networks. There has also been work relating to the implementation of cross-layer interactions. It is high time that these various individual efforts be put into perspective and a more holistic view be taken. In this article, we take a step in that direction by presenting a survey of the literature in the area of cross-layer design, and by taking stock of the ongoing work. We suggest a definition for cross-layer design, discuss the basic types of cross-layer design with examples drawn from the literature, and categorize the initial proposals on how cross-layer interactions may be implemented. We then highlight some open challenges and new opportunities for cross-layer design. Designers presenting cross-layer design proposals can start addressing these as they move ahead.

1,057 citations

Proceedings ArticleDOI
11 Nov 2001
TL;DR: Red-PD (Random Early Detection-Preferential Dropping) is presented, a mechanism that combines simplicity and protection by keeping state for just the high-bandwidth flows by using the packet drop history at the router to detect high- bandwidth flows in times of congestion and preferentially drops packets from these flows.
Abstract: FIFO queueing is simple but does not protect traffic from high-bandwidth flows, which include not only flows that fail to use end-to-end congestion control, but also short round-trip time TCP flows. At the other extreme, per-flow scheduling mechanisms provide max-min fairness but are more complex, keeping state for all flows going through the router. This paper presents RED-PD (Random Early Detection-Preferential Dropping), a mechanism that combines simplicity and protection by keeping state for just the high-bandwidth flows. RED-PD uses the packet drop history at the router to detect high-bandwidth flows in times of congestion and preferentially drops packets from these flows. This paper discusses the design decisions underlying RED-PD. We show that it is effective at controlling high-bandwidth flows using a small amount of state and very simple fast-path operations.

362 citations

Patent
10 Sep 2004
TL;DR: In this paper, the authors present a method and apparatus for granular management of network resources by accessing network device resources through associated references, where the references are group names, and one or more resources within each network device in a telecommunications network may be linked with one of the group names.
Abstract: The present invention provides a method and apparatus for granular management of network resources by accessing network device resources through associated references. In one embodiment, the references are group names, and one or more resources (i.e., a resource collection) within each network device in a telecommunications network may be linked with one or more group names. Group names (or other types of references) may then be used to limit a user's access to particular network device resources. That is, a user may only have access to those resources associated with group names to which the user has access. Over time, network device resources may be associated or disassociated with particular group names. As a result, group names provide users with dynamic access to network device resources. In one embodiment, the groups to which a user has access are defined within a user profile associated with the user. Grouping network device resources, therefore, allows for a granular view of each network device in the network by limiting a user's access to those resources corresponding to group names listed in their user profile. As one example, grouping may allow for customer network management—that is a customer's view is limited to only those network device resources for which they have subscribed.

346 citations

Patent
Hang Zhang1, Jianglei Ma1, Peiying Zhu1, Mo-Han Fong1, Wen Tong1 
14 Sep 2012
TL;DR: In this article, methods and systems for use with wireless networks having one or more cell in which each cell includes a base station (BS), at least one relay station (RS) and at least mobile station (MS).
Abstract: Methods and systems are provided for use with wireless networks having one or more cell in which each cell includes a base station (BS), at least one relay station (RS) and at least one mobile station (MS). The at least one relay station can be used as an intermediate station for providing communication between the BS and MS. Methods are provided for allocating OFDM resources for communicating between the BS, RS and/or MS for example dividing transmission resources into uplink and downlink transmissions and methods of inserting pilot symbols into transmission resources used by the RS. In some embodiments on the invention, the methods are consistent and/or can be used in conjunction with existing standards such as 802.16e.

214 citations

Journal ArticleDOI
TL;DR: In this article, the authors present an investigation into the industry-specific factors that limit the adoption of robotics and automated systems in the construction industry, focusing on three focus groups with 28 experts and an online questionnaire were conducted.
Abstract: The construction industry is a major economic sector, but it is plagued with inefficiencies and low productivity. Robotics and automated systems have the potential to address these shortcomings; however, the level of adoption in the construction industry is very low. This paper presents an investigation into the industry-specific factors that limit the adoption in the construction industry. A mixed research method was employed combining literature review, qualitative and quantitative data collection and analysis. Three focus groups with 28 experts and an online questionnaire were conducted. Principal component and correlation analyses were conducted to group the identified factors and find hidden correlations. The main identified challenges were grouped into four categories and ranked in order of importance: contractor-side economic factors, client-side economic factors, technical and work-culture factors, and weak business case factors. No strong correlation was found among factors. This study will help stakeholders to understand the main industry-specific factors limiting the adoption of robotics and automated systems in the construction industry. The presented findings will support stakeholders to devise mitigation strategies.

210 citations