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The purpose of this paper is to develop a methodology for detecting tree trunks for autonomous agricultural applications performed using mobile robots.

The system is constructed by following the principles of Voronoi diagram method which is one of the machine learning algorithms used by the robotics, mechatronics and automation researchers.

To analyze the accuracy and performance and to make verification and evaluation, both simulation and experimental studies are conducted. The results indicate that the tree trunk detection system developed using Voronoi diagram method can be able to detect tree trunks with high precision.

A novel solution technique to detect tree trunks is proposed. The adaptation of Voronoi diagram method in an agricultural (orchard) task is presented.

As an important connecting component, the reliability of aluminium alloy welded joints influences the whole structural effectiveness and stability of equipment. The purpose of this paper is to propose a novel reliability estimation approach to the welded joints based on time-transformed Wiener process with automatic image measurement of crack growth. The crack length information of the welded joints is incorporated into reliability analysis to reflect the product time-varying characteristics.

The proposed approach is superior to other crack growth estimations in that it innovatively introduce a non-contact and flexible photogrammetry technique.First, on-line crack growth images of aluminium alloy welded joints are acquired by the designed monitor system. Second, crack length is calculated with image measurement, then the crack growth data during the manufacturing process is prepared. Finally, a time-transformed Wiener process is used to modeling the degradation, and reliability estimation is carried out with Wiener model. The approach has been validated on five 7075-T7351 welded joint samples.

The method has a twofold task: first, the extraction of crack length growth data by a sequence of image processing. The main step is to model the crack skeleton with crack skeleton tree, and remove it edges to calculate the length of crack; second, the prediction of crack growth and reliability estimation.

The limitation of proposed method should not be ignored. The pixel/mm scale should be calibrated in advance that means once we have built the monitor system, the relative position of the CCD camera and the surveyed crack cannot change anymore. It has reduced the flexibility. To improve this, we can obtain binocular vision in crack image measurement. The 3-D measurements could solve calibration problem and provide more information, such as the depth and the orientation of crack to research. Therefore, future work can be centered on the improvement of monitor system and measurement precision.

In the paper a novel method to estimate reliability of crack growth from welded joint based on image measurement has been presented. This method could be widely applied in different filed of manufacturing systems, reliability engineering and structural analysis.

This paper aims to present object or feature segmentation from an ordered 3D point cloud range data obtained from a laser scanner for the purpose of robot navigation.

Rotating multi-beam laser scanners provide ordered 3D range data. Differences between consecutive ranges in radial direction are used to compute a novel measure of terrain unevenness at each data point. Computed over a complete rotation, an unevenness field is formed surrounding the scanner. A part of this field staying below a threshold is recognized as ground and removed. Remaining non-ground points are segmented into objects by region growing with points whose unevenness lies within pre-specified limiting values.

The proposed unevenness attribute is simple and efficient for segmenting distinct objects or features. The fineness of surface features can be regulated by adjusting the threshold value of difference in unevenness between neighbouring points that triggers an onset of new segments.

The angles between neighbouring laser range data are assumed to be known.

Segmented objects or features can be used for scan registration, object tracking and robot navigation.

The method may find use in autonomous robots and driverless cars.

Differences between consecutive range data are used imaginatively to derive a novel measure of terrain unevenness, which in turn, is used for efficient segmentation of objects and features.

To describe the prototype macadamia nut yield monitor.

In this paper, the machine vision‐based yield monitor for macadamia nut plantations is described. A summary of sensor fusion procedures is presented. Additionally, a summary of current testing progress is provided.

Using vision to count nuts has the potential to revolutionise yield monitoring for the macadamia industry. Additionally, using a vision sensor for in‐field location can provide a low cost, highly accurate method of positioning. Tractor (and nut) location can be determined accurate to 12 mm.

This project has culminated in the creation of a working prototype harvester. A commercial unit is in the design stage for operation in 2007 harvest season.

This paper describes the solution to a particular problem in the macadamia industry, with potential use in wider fields.

This article aims to compare the LiDAR handheld mobile laser scanner (HMLS) scans with traditional survey methods, as the tree gauge and the hypsometer, to study the efficiency of the new technology in relation to the accuracy of structural forest attributes estimation useful to support a sustainable forest management.

A case study was carried out in a high forest located in Tuscany (Italy), by considering 5 forest types, in 20 different survey plots. A comparative analysis between two survey methods will be shown in order to verify the potential limits and the viability of the LiDAR HMLS in the forest field.

This research demonstrates that LiDAR HMLS technology allows to obtain a large amount of valuable data on forest structural parameters in a short span of time with a high level of accuracy and with obvious impact in terms of organisational efficiency.

Findings could be useful for forest owners highlighting the importance of investing in science and technology to improve the overall efficiency of forest resources management.

This article adds to the current knowledge on the precision forestry topic by providing insight on the feasibility and effectiveness of using precision technologies for monitoring forest ecosystems and dynamics. In particular, this study fills the gap in the literature linked to the need to have practical examples of the use of innovative technologies in forestry.

This article provides a broad overview of telecommunications and network‐related technologies. Topics covered include identification and review of network elements, analog and digital signals, synchronous and asynchronous transmission formats, transmission media and equipment, transmission techniques and characteristics, multiplexing, network types, access technologies, network architectures and topologies, local‐area network technologies and attributes, protocols and protocol issues, gateways, internetworking, local networking alternatives, equipment certification, and various aspects of network management. It is intended to provide the practicing professional in the field of library and information science with a broad, up‐to‐date technical review that might serve to support and facilitate further investigation of current developments in networks and networking. Although the broad range of topics is not treated in depth, numerous references are provided for further investigation.

The purpose of this paper is to assess the impact of human factor on ecological conditions of Moroccan cedar forest with a view to drawing out implication for sustainable forest management. The study is set against the backdrop of the global depletion of natural capital in a rare axis which, if not brought under an integrated sustainability purview, might lead to the extinction of this quickly receding natural resource.

Data for this research are mined from publicly held databases but processed through a time series regression analysis in a way that measures variations in ecological/environmental variables.

Findings reveal that changes in precipitation and temperature account for a small but significant amount of variation during the period 1940-2006. However, most of the decline is attributable to human activities such as overgrazing and illegal logging. These are having far-reaching implications for forest conservation management.

Human agency, more than any effect of nature, is chiefly responsible for the unsustainable development in this sphere of natural capital. Whilst this may not altogether constitute new knowledge, the paper highlights ambivalent positions that both promote and constrain efforts to sustain cedar forest. Its novelty lies not only in the empirical substantiation it affords but also in ferreting out strategic initiatives to dis-incentivise unsustainable exploitation of this important aspect of natural capital.

Index by subjects, compiled by K.G.B. Bakewell covering the following journals: Facilities Volumes 8‐17; Journal of Property Investment & Finance Volumes 8‐17; Property Management Volumes 8‐17; Structural Survey Volumes 8‐17.

Compiled by K.G.B. Bakewell covering the following journals published by MCB University Press: Facilities Volumes 8‐17; Journal of Property Investment & Finance Volumes 8‐17; Property Management Volumes 8‐17; Structural Survey Volumes 8‐17.