Timber grading seminar - Some things you should know about how strength grading works and what is changing in the standards.

Presentations from the seminar on timber grading. "This grading seminar will give you a crash course in timber strength grading, what it is, how it works, and how it is changing. It aims to demystify timber grading, tackle some widely held misconceptions, and tell you the things you need to be aware of to improve profitability, and remain correct and safe in what you do. The timber resource in the UK is changing, technology is advancing, and standards are being modified. This seminar will bring you the latest position, informed by CEN and BSI standards committee work and research conducted by the SIRT network."

Strength grading of sawn timber in Europe: an explanation for engineers and researchers.

This paper is a concise explanation of the normative background to strength grading in Europe, addressing important aspects that are commonly misunderstood by structural engineers and timber researchers. It also highlights changes that are being made to the standards to: incorporate requirements of the construction products regulations; add improvements to the system to accommodate the latest knowledge and technology; and widen the application of the standards. Where designs need to be optimised, there is an opportunity to use the system more intelligently, in combination with the latest technology, to better fit design values to the true properties of the timber resource. This can bring a design enhancement equivalent to effort improving other aspects of the structure, such as connectors and reinforcement. Parallel to this, researchers working on other aspects of structural improvement need to understand what grades really mean in respect of the properties of the timber, in order to correctly analyse the results of testing. It is also useful to know how techniques used in grading can assist with material properties characterisation for research. The amount of destructive testing involved in establishing machine grading settings and visual grading assignments presents a barrier to greater use of local timber, and diversification of commercial species, so it is important that any researcher assessing the properties of such species should consider, from the outset, doing the research in a way that can contribute to a grading dataset at a later date. This paper provides an overview of what is required for this.

Checklists for grading object-oriented CS1 programs: concepts and misconceptions

Sanders, K. and Thomas, L. 2007. Checklists for grading object-oriented CS1 programs: concepts and misconceptions. In Proceedings of the 12th Annual SIGCSE Conference on innovation and Technology in Computer Science Education (Dundee, Scotland, June 25 - 27, 2007). ITiCSE '07. ACM, New York, NY, 166-170

A machine vision approach to the grading of crushed aggregate

The grading of crushed aggregate is carried out usually by sieving. We describe a new image-based approach to the automatic grading of such materials. The operational problem addressed is where the camera is located directly over a conveyor belt. Our approach characterizes the information content of each image, taking into account relative variation in the pixel data, and resolution scale. In feature space, we find very good class separation using a multidimensional linear classifier. The innovation in this work includes (i) introducing an effective image-based approach into this application area, and (ii) our supervised classification using wavelet entropy-based features.

An automated machine vision system for the histological grading of cervical intraepithelial neoplasia (CIN)

The histological grading of cervical intraepithelial neoplasia (CIN) remains subjective, resulting in inter- and intra-observer variation and poor reproducibility in the grading of cervical lesions. This study has attempted to develop an objective grading system using automated machine vision. The architectural features of cervical squamous epithelium are quantitatively analysed using a combination of computerized digital image processing and Delaunay triangulation analysis; 230 images digitally captured from cases previously classified by a gynaecological pathologist included normal cervical squamous epithelium (n = 30), koilocytosis (n = 46), CIN 1 (n = 52), CIN 2 (n = 56), and CIN 3 (n=46). Intra- and inter-observer variation had kappa values of 0.502 and 0.415, respectively. A machine vision system was developed in KS400 macro programming language to segment and mark the centres of all nuclei within the epithelium. By object-oriented analysis of image components, the positional information of nuclei was used to construct a Delaunay triangulation mesh. Each mesh was analysed to compute triangle dimensions including the mean triangle area, the mean triangle edge length, and the number of triangles per unit area, giving an individual quantitative profile of measurements for each case. Discriminant analysis of the geometric data revealed the significant discriminatory variables from which a classification score was derived. The scoring system distinguished between normal and CIN 3 in 98.7% of cases and between koilocytosis and CIN 1 in 76.5% of cases, but only 62.3% of the CIN cases were classified into the correct group, with the CIN 2 group showing the highest rate of misclassification. Graphical plots of triangulation data demonstrated the continuum of morphological change from normal squamous epithelium to the highest grade of CIN, with overlapping of the groups originally defined by the pathologists. This study shows that automated location of nuclei in cervical biopsies using computerized image analysis is possible. Analysis of positional information enables quantitative evaluation of architectural features in CIN using Delaunay triangulation meshes, which is effective in the objective classification of CIN. This demonstrates the future potential of automated machine vision systems in diagnostic histopathology. Copyright (C) 2000 John Wiley and Sons, Ltd.

Grading gems: Appraising the quality of research about social work and social care.

The impetus towards basing practice and policy decisions more explicitly on sound research requires tools to facilitate the systematic appraisal of the quality of research encompassing a diverse range of methods and designs. Five exemplar tools were developed and assessed in terms of their usefulness in selecting studies for inclusion in a systematic review. The widely used ‘hierarchy of evidence’ was adapted and used to appraise internal validity. Four tools were then developed to appraise the external validity dimensions of generalizability (two scales) and methods of data collection (two scales). Methods of combining the scores generated by each tool were explored. Qualitative and quantitative studies were appraised, not separated into two spheres but by using complementary tools developed to appraise different aspects of rigour. There was a high level of agreement between researchers in applying the tools to twenty-two studies on decision making by professionals about the longterm care of older people. The scales for internal validity and generalizability discriminated between the qualities of studies appropriately. The two tools to appraise data collection gave diverse results. Excluding studies that scored in the lowest category on any scale appeared to be the scoring system that was most justifiable. This approach is presented to stimulate debate about the practical application of the evidence-based initiative to social work and social care. This study may assist in developing clearer definitions and common language about appraising rigour that should further the process of selecting robust research for synthesis to inform practice and policy decisions.