Thermochemical characterisation of straws and high yielding perennial grasses

The research is concerned with thermochemical characterisation of straws and high yielding perennial grasses. Crops selected for this study include wheat straw (Triticum aestivum), rape straw (Brassica napus), reed canary grass (Phalaris arundinacea) and switch grass (Panicum virgatum). Thermogravimetric analysis (TGA) was used to examine the distribution of char and volatiles during pyrolysis up to 900 °C. Utilising multi-heating rate thermogravimetric data, the Friedman iso-conversional kinetic method was used to determine pyrolysis kinetic parameters. Light and medium volatile decomposition products were investigated using pyrolysis–gas chromatography–mass spectrometry (Py–GC–MS) up to 520 °C. The 22 highest yielding identifiable cellulose, hemicellulose and lignin biomass markers were semi-quantified taking into consideration peak areas from GC chromatograms. Notable differences can be seen in butanedioic acid, dimethyl ester (hemicelluloses decomposition products), 2-methoxy-4-vinylphenol (lignin marker) and levoglucosan (intermediate pyrolytic decomposition product of cellulose) content when comparing perennial grasses with straw. From results presented in this study, perennial grasses such as switch grass, have the most attractive properties for fast pyrolysis processing. This is because of the observed high volatile yield content of 82.23%, heating value of 19.64 MJ/kg and the relatively low inorganic content.

Computer aided manufacturing of geometric models

As systems for computer-aided-design and production of mechanical parts have developed, there has arisen a need for techniques for the comprehensive description of the desired part, including its 3-D shape. The creation and manipulation of shapes is generally known as geometric modelling. It is desirable that links be established between geometric modellers and machining programs. Currently, unbounded APT and some bounded geometry systems are being widely used in manufacturing industry for machining operations such as: milling, drilling, boring and turning, applied mainly to engineering parts. APT systems, however, are presently only linked to wire-frame drafting systems. The combination of a geometric modeller and APT will provide a powerful manufacturing system for industry from the initial design right through part manufacture using NC machines. This thesis describes a recently developed interface (ROMAPT) between a bounded geometry modeller (ROMULUS) and an unbounded NC processor (APT). A new set of theoretical functions and practical algorithms for the computer aided manufacturing of 3D solid geometric model has been investigated. This work has led to the development of a sophisticated computer program, ROMAPT, which provides a new link between CAD (in form of a goemetric modeller ROMULUS) and CAM (in form of the APT NC system). ROMAPT has been used to machine some engineering prototypes successfully both in soft foam material and aluminium. It has been demonstrated above that the theory and algorithms developed by the author for the development of computer aided manufacturing of 3D solid modelling are both valid and applicable. ROMAPT allows the full potential of a solid geometric modeller (ROMULUS) to be further exploited for NC applications without requiring major investment in new NC processor. ROMAPT supports output in APT-AC, APT4 and the CAM-I SSRI NC languages.

A review of multi-factor capacity expansion models for manufacturing plants:searching for a holistic decision aid

Investment in capacity expansion remains one of the most critical decisions for a manufacturing organisation with global production facilities. Multiple factors need to be considered making the decision process very complex. The purpose of this paper is to establish the state-of-the-art in multi-factor models for capacity expansion of manufacturing plants within a corporation. The research programme consisting of an extensive literature review and a structured assessment of the strengths and weaknesses of the current research is presented. The study found that there is a wealth of mathematical multi-factor models for evaluating capacity expansion decisions however no single contribution captures all the different facets of the problem.

Strategic positioning of manufacturing operations within global supply chains

In global environment, a company has to make many decisions that impact upon its position in global supply chain networks such as outsourcing, offshoring, joint venture, vertical/horizontal integration, etc. All these decisions impact on the company’s strategic position, and hence on competitive space and performance. Therefore, it is important for a company to carefully manage strategic positioning by making careful decisions about the adoption of alternative manufacturing and supply chain activities. Unfortunately, there is no complete process studied in strategic positioning of manufacturing operations within global supply chain. Therefore, the work presented in this paper has investigated leading research and industrial practices to create a formal and rational decision process. An analysis of previous literature, industrial practices, and the resulting decision process are all presented in this paper.

Integrated strategic supply chain positioning for SME's:an empirical study

Purpose – The purpose of this paper is to report on an investigation into the selection and evaluation of a suitable strategic positioning methodology for SMEs in Singapore. Design/methodology/approach – The research methodology is based on critical review of the literature to identify the potentially most suitable strategic positioning methodology, evaluation and testing of the methodology within the context of SME's in Singapore, and analysis to determine the strengths and weaknesses of the methodology and opportunities for further research. Findings – This paper illustrates a leading integrated strategic positioning decision making process, which has been found to be potentially suitable for SMEs in Singapore, and the process is then applied and evaluated in two industrial case studies. Results in the form of strengths, weaknesses and opportunities are evaluated and discussed in detail, and further research to improve the process has been identified. Practical implications – A practical and integrated strategic supply chain positioning methodology for SMEs to define their own competitive space, among other companies in the manufacturing supply chain, so as to maximize business competitiveness. Originality/value – This paper contributes to the knowledge of the strategic positioning decision process as well as identifies further research to adapt the process for SMEs in Singapore.

A review of research in manufacturing prognostics

With the fast changing global business landscape, manufacturing companies are facing increasing challenge to reduce cost of production, increase equipment utilization and provide innovative products in order to compete with countries with low labour cost and production cost. On of the methods is zero down time. Unfortunately, the current research and industrial solution does not provide user friendly development environment to create “Adaptive microprocessor size with supercomputer performance” solution to reduce downtime. Most of the solutions are PC based computer with off the shelf research software tools which is inadequate for the space constraint manufacturing environment in developed countries. On the other hand, to develop solution for various manufacturing domain will take too much time, there is lacking tools available for rapid or adaptive way of create the solution. Therefore, this research is to understand the needs, trends, gaps of manufacturing prognostics and defines the research potential related to rapid embedded system framework for prognostic.

Clonal composition of human adamantinomatous craniopharyngiomas and somatic mutation analyses of the patched (PTCH), Gsα and Gi2α genes

Craniopharyngioma is the most common childhood tumor and thought to arise from embryonic remnants of Rathke's pouch. The paucity of published data on the molecular basis of these tumors prompted us to examine 22 adamantinomatous craniopharyngiomas looking for genetic abnormalities. Using the X-linked polymorphic androgen receptor gene as a tool for X-chromosome inactivating analysis, we found that a subset of craniopharyngiomas are monoclonal and therefore are probably due to acquired somatic genetic defects. Thus, we investigated these tumours for mutations within three candidate genes, Gsα, Gi2α and patched (PTCH). Using single stranded conformational polymorphism (SSCP), denaturing gradient gel electrophoresis and direct sequencing, the presence of somatic mutations in these genes could not be demonstrated in any tumor. Our data indicate that a subset of craniopharyngiomas are monoclonal and the mutations in the PTCH, Gsα, and Gi2α contribute little if any to cranipharyngioma development.

Are guanxi-type supervisor-subordinate relationships culture-general? An eight-nation test of measurement invariance

Three dimensions of subordinate-supervisor relations (affective attachment, deference to supervisor, and personal-life inclusion) that had been found by Y. Chen, Friedman, Yu, Fang, and Lu to be characteristic of a guanxi relationship between subordinates and their supervisors in China were surveyed in Taiwan, Singapore, and six non-Chinese cultural contexts. The Affective Attachment and Deference subscales demonstrated full metric invariance whereas the Personal-Life Inclusion subscale was found to have partial metric invariance across all eight samples. Structural equation modeling revealed that the affective attachment dimension had a cross-nationally invariant positive relationship to affective organizational commitment and a negative relationship to turnover intention. The deference to the supervisor dimension had invariant positive relationships with both affective and normative organizational commitment. The personal-life inclusion dimension was unrelated to all outcomes. These results indicate the relevance of aspects of guanxi to superior-subordinate relations in non-Chinese cultures. Studies of indigenous concepts can contribute to a broader understanding of organizational behavior. © The Author(s) 2014.

Comparative genomic hybridization analysis of craniopharyngiomas

Object. Craniopharyngioma is the most common childhood brain tumor and is thought to arise from embryonic remnants of the Rathke pouch. Some craniopharyngiomas are monoclonal in origin and hence presumably harbor somatic genetic alterations, although the precise molecular mechanisms involved in craniopharyngioma development are unknown. The goal of this study was to identify genetic alterations in craniopharyngiomas. Methods. To gain insight into the molecular mechanisms involved in development of these tumors, the authors analyzed nine adamantinomatous craniopharyngiomas by using comparative genomic hybridization. Six tumors (67%) displayed at least one genomic alteration, and three had six or more alterations. Only two tumors displayed a decrease in DNA copy number, and in all others an increase in DNA copy number was noted. Conclusions. The authors conclude that a subset of craniopharyngiomas consists of monoclonal tumors arising from activation of oncogenes located at specific chromosomal loci.

Kinetic study of the pyrolysis of miscanthus and its acid hydrolysis residue by thermogravimetric analysis

The kinetic parameters of the pyrolysis of miscanthus and its acid hydrolysis residue (AHR) were determined using thermogravimetric analysis (TGA). The AHR was produced at the University of Limerick by treating miscanthus with 5 wt.% sulphuric acid at 175 °C as representative of a lignocellulosic acid hydrolysis product. For the TGA experiments, 3 to 6 g of sample, milled and sieved to a particle size below 250 μm, were placed in the TGA ceramic crucible. The experiments were carried out under non-isothermal conditions heating the samples from 50 to 900 °C at heating rates of 2.5, 5, 10, 17 and 25 °C/min. The activation energy (EA) of the decomposition process was determined from the TGA data by differential analysis (Friedman) and three isoconversional methods of integral analysis (Kissinger–Akahira–Sunose, Ozawa–Flynn–Wall, Vyazovkin). The activation energy ranged from 129 to 156 kJ/mol for miscanthus and from 200 to 376 kJ/mol for AHR increasing with increasing conversion. The reaction model was selected using the non-linear least squares method and the pre-exponential factor was calculated from the Arrhenius approximation. The results showed that the best fitting reaction model was the third order reaction for both feedstocks. The pre-exponential factor was in the range of 5.6 × 1010 to 3.9 × 10+ 13 min− 1 for miscanthus and 2.1 × 1016 to 7.7 × 1025 min− 1 for AHR.

Repeatability of ocular aberration measurements in patients with keratoconus

Purpose: To explore the repeatability of lower-order and higher-order ocular aberrations measured in patients with keratoconus. Methods: The IRX-3 (Imagine Eyes, Paris, France) aberrometer was used to record lower-order and higher-order aberrations in 31 eyes of 31 patients with keratoconus. Four monocular measurements were taken consecutively for each patient. The aberrometry data were analysed up to the 5th Zernike order for a 4-mm pupil diameter. The data were evaluated using repeated-measures anova and Friedman analyses. Repeatability was analysed using within-subject standard deviation (SW) and the repeatability limit (r) calculated as 1.96 ×√2×Sw. Results: Of the 11 aberration terms evaluated, the repeatability of Z (2,0) (mean= 1.36μm; SW=0.09μm; r=0.26μm); Z (2,±2) RMS (mean=1.05μm; SW= 0.09μm; r=0.24μm) and Z (4,0) aberrations (mean=0.34μm; SW=0.09 μm; r=0.24μm) showed the highest variability. In contrast, Z (3,±1) RMS aberrations (mean=0.85μm; SW=0.06μm; r=0.16μm) and Z (4,±2) RMS aberrations (mean=0.40μm; SW=0.07μm; r=0.18μm) showed comparatively better repeatability. Conclusions: The lower-order and higher-order aberrations measured in this group of keratoconic patients showed higher levels of variability compared to previous investigations of visually-normal subjects. These results may be of interest to eyecare practitioners involved in the design and fitting of aberration-controlling contact lenses for patients with keratoconus. © 2011 The College of Optometrists.

Acumen : an open-source testbed for cyber-physical systems research

Developing Cyber-Physical Systems requires methods and tools to support simulation and verification of hybrid (both continuous and discrete) models. The Acumen modeling and simulation language is an open source testbed for exploring the design space of what rigorousbut- practical next-generation tools can deliver to developers of Cyber- Physical Systems. Like verification tools, a design goal for Acumen is to provide rigorous results. Like simulation tools, it aims to be intuitive, practical, and scalable. However, it is far from evident whether these two goals can be achieved simultaneously. This paper explains the primary design goals for Acumen, the core challenges that must be addressed in order to achieve these goals, the “agile research method” taken by the project, the steps taken to realize these goals, the key lessons learned, and the emerging language design.