Frequent subgraph mining algorithms on weighted graphs

This thesis describes research work undertaken in the field of graph-based knowledge discovery (or graph mining). The objective of the research is to investigate the benefits that the concept of weighted frequent subgraph mining can offer in the context of the graph model based classification. Weighted subgraphs are graphs where some of the vertexes/edges are considered to be more significant than others. How to discover frequent sub-structures with different strengths is the main issue to be resolved in this thesis. The main approach to addressing this issue is to integrate weight constraints into the frequent subgraph mining process. It is suggested that the utilization of weighted frequent subgraph mining generates more discriminate and significant subgraphs, which will have application in, for example, the classification and clustering of graph data

Frequent subgraph mining algorithms on weighted graphs

This thesis describes research work undertaken in the field of graph-based knowledge discovery (or graph mining). The objective of the research is to investigate the benefits that the concept of weighted frequent subgraph mining can offer in the context of the graph model based classification. Weighted subgraphs are graphs where some of the vertexes/edges are considered to be more significant than others. How to discover frequent sub-structures with different strengths is the main issue to be resolved in this thesis. The main approach to addressing this issue is to integrate weight constraints into the frequent subgraph mining process. It is suggested that the utilization of weighted frequent subgraph mining generates more discriminate and significant subgraphs, which will have application in, for example, the classification and clustering of graph data.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Tracking and abstracting construction site documentation

This paper addresses how best to capture the as-built story of construction projects through site documents so that construction professionals can effectively track what happened during the construction process, solve problems, pursue valid claims, and extract lessons learnt for use on future projects. At present in the construction industry, only a subset of site documents are in electronic format, and software packages used to create site records are usually not compatible with each other; such facts make it very difficult and costly to manage all records directly. This study is based on the premise that creating electronic abstractions of key site documents is an approach not only feasible but also practical to capture their essence. This study examines both the strengths and weaknesses of the traditional hard copy practice of the industry, and how this practice can be enhanced using Information Technology such that current system advantages are retained and new benefits are derived. Building on previous works, the audience of this research work consists of construction firms and public agencies that oversee the construction of buildings and civil infrastructure. The methodology used in conducting this study involved a thorough review of the literature, including past theses on related topics, an examination of the state-of-the- art as reflected in current commercial software, and a field study of on site documentation practices based on two periods of site observation with a project management firm in a high rise building project. The results of the research were implemented in a research system directed at the needs of industry, which features a multiple-view description of construction projects. Generic properties and some custom properties for abstracting site documents have been identified. The ability to search through these abstractions has also been explored. The ultimate goal is to be able to query the system for all information within the multiple view representation pertaining to a user specified issue. This includes the identification of the relevant documents, physical components, schedule performance, and problems encountered.Applied Science, Faculty ofCivil Engineering, Department ofGraduat

Thioetherimide-Modified Cyanate Ester Resin with Better Molding Performance for Glass Fiber Reinforced Composites

Cyanate ester (CE) resins with higher heat resistance, lower coefficients of thermal expansion (CTEs), and lower water absorption ratios are highly desired in printed circuit boards (PCBs). In this work, a CE was modified by copolymerization with a long-chain thioether bismaleimide (SBMI) to form a thioetherimide-modified CE (SBT). The results indicated that SBT had a wider processing window and better processing properties than a common bismaleimide-modified CE resin (MBMI). After molding with a glass fiber cloth, the composites (GSBT) exhibited moisture adsorption in the range of 1.4%–2.0%, high tensile strength in the range of 311–439 MPa, good mechanical retention of 70%–85% even at 200 °C, and good dimension stability, with coefficients of thermal expansion in the range of 17.3–18.6 (×10−6 m/°C). Such GSBT composites with superior properties would be good candidates for PCB applications

Study on Numerical Simulation Test of Mining Surface Subsidence Law under Ultrathick Loose Layer

In the process of coal mining, the surface subsidence under ultrathick loose layer is abnormal (subsidence coefficient greater than 1.0), which will cause great damage to the surface ecological environment. The fracture propagation and stress evolution of bedrock are of great significance to the prevention of surface subsidence. Taking the 1305 working face of a mine as the background, this paper study the process of crack propagation and stress evolution of bedrock under the influence of ultrathick loose layer by methods of on-site measurement, similar simulation, and numerical simulation. During the research process, the physical model was verified by the measured data. Then, the numerical model was verified by the crack propagation angle and subsidence of bedrock, which were obtained in a similar simulation. Based on the verified numerical model, it was obtained that after the coal seam was mined out, the bedrock above the mined-out area was mainly damaged by tension, while the strata on both sides of the crack expansion angle were mainly damaged by shear and tension. During coal seam mining, for bedrock the process of fracture expansion, subsidence, and stress evolution all could be divided into four stages. This research provides a basis for the control of surface subsidence