Haifa - Harbor Construction

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Haifa - Harbor Construction

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Structural Veneer Based Composite Products from Hardwood Thinning - Part I: Background and Manufacturing

In Australia, plantation forests have increased in area by around 50% in the last 10 years. While this expansion has seen a modest 8% increase for softwoods, hardwood plantations have dramatically increased by over 150%. Hardwood plantations grown for high quality sawn timber are slow to mature, with a crop rotation time potentially reaching 35 years. With this long lead-time, each year the risk from fire, pests and adverse weather events dramatically increases, while not translating into substantially higher financial returns to the grower. To justify continued expansion of Australia's current hardwood plantation estate, it is becoming necessary to develop higher value end-uses for both pulpwood and smaller 'sawlog' resources. The use of the low commercial value stems currently culled during thinning appears to be a necessary option to improve the industry profitability and win new markets. This paper provides background information on Australian forests and plantations and gives an overview of potential uses of Australian hardwood plantation thinning logs, as their mechanical properties. More specifically, this paper reports on the development of structural Veneer Based Composite (VBC) products from hardwood plantation thinning logs, taking advantage of a recent technology developed to optimise the processing of this resource. The process used to manufacture a range of hollow-form veneer laminated structural products is presented and the mechanical characteristics of these products are investigated in the companion paper. The market applications and future opportunities for the proposed products are also discussed, as potential benefits to the timber industry. © RILEM 2014.

Quick abnormal-bid-detection method for construction contract auctions

Non-competitive bids have recently become a major concern in both Public and Private sector construction contract auctions. Consequently, several models have been developed to help identify bidders potentially involved in collusive practices. However, most of these models require complex calculations and extensive information that is difficult to obtain. The aim of this paper is to utilize recent developments for detecting abnormal bids in capped auctions (auctions with an upper bid limit set by the auctioner) and extend them to the more conventional uncapped auctions (where no such limits are set). To accomplish this, a new method is developed for estimating the values of bid distribution supports by using the solution to what has become known as the German tank problem. The model is then demonstrated and tested on a sample of real construction bid data and shown to detect cover bids with high accuracy. This work contributes to an improved understanding of abnormal bid behavior as an aid to detecting and monitoring potential collusive bid practices.

Regio- and stereoselectivity of oxidative coupling reactions of phenols : Spirodienones as construction units in lignin

Dimeric phenolic compounds lignans and dilignols form in the so-called oxidative coupling reaction of phenols. Enzymes such as peroxidases and lac-cases catalyze the reaction using hydrogen peroxide or oxygen respectively as oxidant generating phenoxy radicals which couple together according to certain rules. In this thesis, the effects of the structures of starting materials mono-lignols and the effects of reaction conditions such as pH and solvent system on this coupling mechanism and on its regio- and stereoselectivity have been studied. After the primary coupling of two phenoxy radicals a very reactive quinone me-thide intermediate is formed. This intermediate reacts quickly with a suitable nucleophile which can be, for example, an intramolecular hydroxyl group or another nucleophile such as water, methanol, or a phenolic compound in the reaction system. This reaction is catalyzed by acids. After the nucleophilic addi-tion to the quinone methide, other hydrolytic reactions, rearrangements, and elimination reactions occur leading finally to stable dimeric structures called lignans or dilignols. Similar reactions occur also in the so-called lignification process when monolignol (or dilignol) reacts with the growing lignin polymer. New kinds of structures have been observed in this thesis. The dimeric com-pounds with so-called spirodienone structure have been observed to form both in the dehydrodimerization of methyl sinapate and in the beta-1-type cross-coupling reaction of two different monolignols. This beta-1-type dilignol with a spirodienone structure was the first synthetized and published dilignol model compound, and at present, it has been observed to exist as a fundamental construction unit in lignins. The enantioselectivity of the oxidative coupling reaction was also studied for obtaining enantiopure lignans and dilignols. A rather good enantioselectivity was obtained in the oxidative coupling reaction of two monolignols with chiral auxiliary substituents using peroxidase/H2O2 as an oxidation system. This observation was published as one of the first enantioselective oxidative coupling reaction of phenols. Pure enantiomers of lignans were also obtained by using chiral cryogenic chromatography as a chiral resolution technique. This technique was shown to be an alternative route to prepare enantiopure lignans or lignin model compounds in a preparative scale.

High value timber composite panels from hardwood plantation thinnings.

Identifying processing strategies and products that suit young plantation hardwoods has proved challenging with low product recoveries and/or unmarketable products being the outcome of many trials. The production of rotary veneer has been demonstrated as an effective method for converting plantation hardwood trees. Across nine processing studies that included six different plantation species (Dunn’s white gum, spotted gum, Gympie messmate, spotted gum hybrid, red mahogany and western white gum), simple spindleless lathe technology was used to process 914 veneer billets totally 37.4 m3.

Book Review: "Safe Design and Construction of Machinery – Regulation, Practice and Performance [First edition]"

With Safe Design and Construction of Machinery, the author presents the results of empirical studies into this significant aspect of safety science in a very readable, well-structured format. The book contains 436 references, 17 tables, one figure and a comprehensive index. Liz Bluff addresses a complex and important, but often neglected domain in OHS – the safety of machinery – in a holistic and profound, yet evidence based analysis; with many applied cases from her studies, which make the book accessible and a pleasant lecture. Although research that led to this remarkable publication might have been primarily focused on the regulators, this book can be highly recommended to all OHS academics and practitioners. It provides an important contribution to the body of knowledge in OHS, and establishes one of the few Australian in-depth insights into the significance of machinery producers, rather than machinery users in the wider framework of risk management. The author bases this fresh perspective on the well-established European Machinery Safety guidelines, and grounds her mixed-methods research predominantly in qualitative analysis of motivation and knowledge, which eventually leads to specific safety outcomes. It should be noted that both European and Australian legal aspects are investigated and considered, as both equally apply to many machinery exporters. A detailed description of the research design and methods can be found in an appendix. Overall, the unique combination of quantitative safety performance data and qualitative analysis of safety behaviours form a valuable addition to the understanding of machinery safety. The author must be congratulated on making these complex relationships transparent to the reader through her meticulous inquiry.

Scanning electron microscopy studies of wear in LM13 and LM13-graphite particulate composite

Examination of the structure of worn surfaces has shown that the wear of LM13 and LM13-graphite particulate composite is controlled by the nature and extent of subsurface deformation. The addition of graphite influences the wear characteristics by affecting the plastically deformed zone. The possible mechanisms of wear are discussed.

Prediction of masonry compressive behaviour using a damage mechanics inspired modelling method

Masonry under compression is affected by the properties of its constituents and their interfaces. In spite of extensive investigations of the behaviour of masonry under compression, the information in the literature cannot be regarded as comprehensive due to ongoing inventions of new generation products – for example, polymer modified thin layer mortared masonry and drystack masonry. As comprehensive experimental studies are very expensive, an analytical model inspired by damage mechanics is developed and applied to the prediction of the compressive behaviour of masonry in this paper. The model incorporates a parabolic progressively softening stress-strain curve for the units and a progressively stiffening stress-strain curve until a threshold strain for the combined mortar and the unit-mortar interfaces is reached. The model simulates the mutual constraints imposed by each of these constituents through their respective tensile and compressive behaviour and volumetric changes. The advantage of the model is that it requires only the properties of the constituents and considers masonry as a continuum and computes the average properties of the composite masonry prisms/wallettes; it does not require discretisation of prism or wallette similar to the finite element methods. The capability of the model in capturing the phenomenological behaviour of masonry with appropriate elastic response, stiffness degradation and post peak softening is presented through numerical examples. The fitting of the experimental data to the model parameters is demonstrated through calibration of some selected test data on units and mortar from the literature; the calibrated model is shown to predict the responses of the experimentally determined masonry built using the corresponding units and mortar quite well. Through a series of sensitivity studies, the model is also shown to predict the masonry strength appropriately for changes to the properties of the units and mortar, the mortar joint thickness and the ratio of the height of unit to mortar joint thickness. The unit strength is shown to affect the masonry strength significantly. Although the mortar strength has only a marginal effect, reduction in mortar joint thickness is shown to have a profound effect on the masonry strength. The results obtained from the model are compared with the various provisions in the Australian Masonry Structures Standard AS3700 (2011) and Eurocode 6.

Construction of Stability Multipliers with Prescribed Phase Characteristics: an Improved Value for $\sigma

For a feedback system consisting of a transfer function $G(s)$ in the forward path and a time-varying gain $n(t)(0 \leqq n(t) \leqq k)$ in the feedback loop, a stability multiplier $Z(s)$ has been constructed (and used to prove stability) by Freedman [2] such that $Z(s)(G(s) + {1 / K})$ and $Z(s - \sigma )(0 < \sigma < \sigma _ * )$ are strictly positive real, where $\sigma _ * $ can be computed from a knowledge of the phase-angle characteristic of $G(i\omega ) + {1 / k}$ and the time-varying gain $n(t)$ is restricted by $\sigma _ * $ by means of an integral inequality. In this note it is shown that an improved value for $\sigma _ * $ is possible by making some modifications in his derivation. ©1973 Society for Industrial and Applied Mathematics.

Studies on CNTs/DNA composite

The electrical and optical properties of MWCNTs/DNA composite were studied. Electrical conductivity studies reveal that, the increase in CNTs concentration in DNA increases the conductivity. Fourier transformed Infrared (FTIR) spectrum shows that the CNTs are bonded to DNA covalently at the ends and defects sites and the wrapping of DNA on the CNTs is due to van der Waals force.

Organisational culture and quality management system implementation in Indonesian construction companies

The study of the organisational culture in the construction industry is still in the stage of debate (Oney-Yazıcı et al., 2007). Despite the complexities involved in measuring the culture of the construction industry (Tijhuis and Fellows, 2012), this culture is regarded as being worthy of research, especially in relation to the organisational culture needed to support quality management systems (Koh and Low, 2008; Watson and Howarth, 2011) and to improve organisational effectiveness, and therefore, organisational performance (Coffey, 2010; Cheung et al., 2011). A number of recent studies have examined the construction companies’ organisational culture within the context of the use of Cameron and Quinn’s Competing Value Framework (CVF), as well as the use of their Organizational Culture Assessment Instrument (OCAI) as the conceptual paradigm for the analyses (Thomas et al., 2002; Nummelin, 2006; Oney- Yazıcı et al., 2007; Koh and Low, 2008). However, there has been little research based on the use of Cameron and Quinn’s CVF-OCAI tool for identifying types of construction companies’ organisational culture and their influences on the implementation of QMS-ISO 9001. Research output and information is also very limited relating to the strength of the companies’ organisational culture driving an effective QMS-ISO 9001 implementation, affecting the companies’ effectiveness. To rectify these research gaps, the research has been aimed to study organisational culture types (based on CVF) and their influences on the implementation of QMS-ISO 9001:2008 principles and elements, which eventually lead to improved companies’ quality performance. In order to fully examine the status of the QMS being implemented, the research has studied the relationships of the barriers of QMS implementation with the implementation of QMS-ISO 9001:2008 principles and elements and with the business performance of the companies, as well as the examination of the relationships of the implementation of QMS-ISO 9001:2008 principles and elements with the companies’ business performance. The research output has been the development of fundamental and original studies on the study topics, to provide the knowledge for improvements in Indonesian construction companies’ quality performance and quality outcomes.

Combustion and Thermal Decomposition of Ammonium Perchlorate-Aluminium Composite Pellets: Mechanism for Aluminium Participation

Thermal behaviour of ammonium perchlorate-aluminium composites is studied using differential thermal analysis, thermogravimetry and differential scanning calorimetry. Electrical resistivity studies throw light on the mechanism of ammonium perchlorate decomposition at different aluminium contents. The differences observed in burning behaviour by earlier authors is explained in terms of porosity and thermal conductivity of the composite.

Construction of a global map of human gene expression : the process, tools and analysis

This thesis studies human gene expression space using high throughput gene expression data from DNA microarrays. In molecular biology, high throughput techniques allow numerical measurements of expression of tens of thousands of genes simultaneously. In a single study, this data is traditionally obtained from a limited number of sample types with a small number of replicates. For organism-wide analysis, this data has been largely unavailable and the global structure of human transcriptome has remained unknown. This thesis introduces a human transcriptome map of different biological entities and analysis of its general structure. The map is constructed from gene expression data from the two largest public microarray data repositories, GEO and ArrayExpress. The creation of this map contributed to the development of ArrayExpress by identifying and retrofitting the previously unusable and missing data and by improving the access to its data. It also contributed to creation of several new tools for microarray data manipulation and establishment of data exchange between GEO and ArrayExpress. The data integration for the global map required creation of a new large ontology of human cell types, disease states, organism parts and cell lines. The ontology was used in a new text mining and decision tree based method for automatic conversion of human readable free text microarray data annotations into categorised format. The data comparability and minimisation of the systematic measurement errors that are characteristic to each lab- oratory in this large cross-laboratories integrated dataset, was ensured by computation of a range of microarray data quality metrics and exclusion of incomparable data. The structure of a global map of human gene expression was then explored by principal component analysis and hierarchical clustering using heuristics and help from another purpose built sample ontology. A preface and motivation to the construction and analysis of a global map of human gene expression is given by analysis of two microarray datasets of human malignant melanoma. The analysis of these sets incorporate indirect comparison of statistical methods for finding differentially expressed genes and point to the need to study gene expression on a global level.

Modeling multi-stakeholder multi-objective decisions during public participation in major infrastructure and construction projects: A decision rule approach

Major infrastructure and construction (MIC) projects are those with significant traffic or environmental impact, of strategic and regional significance and high sensitivity. The decision making process of schemes of this type is becoming ever more complicated, especially with the increasing number of stakeholders involved and their growing tendency to defend their own varied interests. Failing to address and meet the concerns and expectations of stakeholders may result in project failures. To avoid this necessitates a systematic participatory approach to facilitate decision-making. Though numerous decision models have been established in previous studies (e.g. ELECTRE methods, the analytic hierarchy process and analytic network process) their applicability in the decision process during stakeholder participation in contemporary MIC projects is still uncertain. To resolve this, the decision rule approach is employed for modeling multi-stakeholder multi-objective project decisions. Through this, the result is obtained naturally according to the “rules” accepted by any stakeholder involved. In this sense, consensus is more likely to be achieved since the process is more convincing and the result is easier to be accepted by all concerned. Appropriate “rules”, comprehensive enough to address multiple objectives while straightforward enough to be understood by multiple stakeholders, are set for resolving conflict and facilitating consensus during the project decision process. The West Kowloon Cultural District (WKCD) project is used as a demonstration case and a focus group meeting is conducted in order to confirm the validity of the model established. The results indicate that the model is objective, reliable and practical enough to cope with real world problems. Finally, a suggested future research agenda is provided.