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Thioindigoid dyestuffs are in an important class of compounds and are used as vat dyes for textile dyeing and printing. This chromophoric system has also found application in the pigment field, especially where suitable substituents in the aromatic nuclei bring about an increase in resistance to solvent bleed and migration. The best example is the reddish‐violet thioindigo bordeaux of light fastness comparable, even in light tints, with the phthalocyanine pigments.

This paper aims to estimate the bearing capacity of a surface strip and circular footings lying on layered sand using numerical limit analysis.

Lower and upper bound limit analysis, as well as finite elements and second-order conic programming (SOCP), are used in this analysis. The yield criterion of Mohr-Coulomb is used to model soil behavior. Using this technique, stringent lower and upper bounds on ultimate bearing capacity can be achieved by assuming an associated flow law.

The obtained results indicate that the exact collapse load is typically being bracketed to within 6% about a mean of both the bounds. The obtained results are compared with the existing literature wherever applicable.

To the best of the authors’ knowledge, no study has used lower and upper bound limit analysis, as well as finite elements and SOCP, to estimate the bearing capacity of a surface strip and circular footings lying on layered sand.

Differential settlement between foundations’ elements induces additional stresses in the structural elements. In general, the amount of settlement that a structure can undergo without distress is large, provided that the structure settles uniformly. However, based on the fact that the soil under the foundation may not be uniform in nature and the loads transferred from the superstructure to the foundation are variable, differential settlements between the foundation elements are expected. The purpose of this paper is to evaluate the stresses induced in a typical ten-storey reinforced concrete building subjected to excessive differential settlement.

In this investigation, excessive differential settlement up to 75 mm is assigned to the center column on the ground floor that represents the most critical case. A three-dimensional finite element model is developed to perform structural analysis using the software SAP2000, and the nonlinear static pushover analysis is performed.

The results of this study show that the building behaves elastically up to 25 mm of differential settlement between its foundation elements, which agrees well with the recommendation given in design manuals. Beyond this value, significant inelastic response is observed in the lower floors and decreases gradually in the higher floors and accordingly, some members have consumed the factor of safety and are in the verge of failure.

Based on the results of this study, recommendations are made for better communication between the structure and the geotechnical engineers to either limit the differential settlements or incorporate these additional stresses during the design stage of the building. Furthermore, the results of the study can be used to recommend to building codes or design manuals to add a load component due to the anticipated differential settlements of the foundation.

Healthcare-sector projects are some of the most complex in modern practice due to their reliance on high-tech components and the level of precision they must maintain. Existing literature in healthcare performance specifically is scarce, but there is a recent increasing trend in both healthcare construction and a corresponding trend in related literature. No previously existing study has derived weights (relative importance) of performance metric in an objective, data-based manner. The purpose of this paper is to present a newly developed mathematical model that derives these weights, free of subjectivity that is common in other literature.

This paper’s model considers 17 exceptional projects and 19 average projects, and reveals the weights (or relative importance) of ten performance metrics by comparing how projects relate to one another in terms of each metric individually. It solves an eigenvalue problem that maximizes the difference between average and exceptional project performances.

The most significant weight, i.e. the performance metric which has the greatest impact on healthcare project performance, was request for information per million dollars with a weight of 16.07 percent. Other highly weighted metrics included construction speed and schedule growth at 13.08 and 12.23 percent, respectively. Rework was the least significant metric at 3.61 percent, but not all metrics of quality had low ratings. Deficiency issues per million dollars was weighted at 11.61 percent, for example. All weights derived by the model in this paper were validated statistically to ensure their applicability as comparison and assessment tools.

There is no widely accepted measure of project performance specific to healthcare construction. This study’s contribution to the body of knowledge is its mathematical model which is a landmark effort to develop a single, objective, unified project performance index for healthcare construction. Furthermore, this unified score presents a user-friendly avenue for contractors to standardize their productivity tracking – a missing piece in the practices of many contractors.

Since Victor Meyer's first report on coupling of diazonium salts with activated carbon compounds, a growing interest has appeared in literature for synthesis and use of different isolated and/or fused nitrogen‐containing heterocyclic dyestuffs as fluorescent whitening agents. A technically important class of these products is those embodying pyrido (1,2‐a) benzimidazole residue in their structure. The parent pyrido (1, 2‐a) benzi‐midazole itself has been previously used in the synthesis of a variety of dyes and pigments.

A series of novel anchored mono‐ and disarylazo cationic pigments embodying long chain aliphatic amine moiety, as deflocculating unit, were prepared by amination of the newly synthesized heterocyclic Hansa Yellow analogue derivatives IVa‐g followed by reacting the products with p‐nitroso‐N,N‐dimethyl aniline. Synthesis and spectral behaviour of these products as well as their precursors were fully investigated. The hitherto prepared organic colourants showed preliminary improved bleeding and fastness properties.

The purpose of this paper is to present a hybrid simulation approach for predicting the value of labor productivity taking account of various continuous influencing factors and the interactions between different agents involved in the project.

The various continuous factors affecting labor productivity are simulated using system dynamics (SD). The heterogeneity of different agents involved in the project and their interactions is accounted using agent-based modelling (ABM). The developed ABM and SD models are finally integrated to simulate the value of labor productivity taking account of all the influencing factors.

The proposed hybrid simulation tool is implemented in a real project to evaluate its perfomance. The value of labor productivity is simulated by taking account of all the influencing factors. The most appropriate execution strategy is then selected using the developed hybrid SD-ABM approach to improve productivity. It is shown that the number of working groups and their movement patterns affect the severity of the groups’ interferences which will in turn affect the value of labor productivity.

This research helps project managers to predict and improve the value of labor productivity taking account of all the influencing factors.

It is believed that the proposed hybrid SD-ABM simulation approach offers a novel and robust tool for modeling labor productivity because the effects of various continuous influencing factors and the interactions between different agents are taken into account through the combination of SD and ABM. Many complex problems faced in construction projects involve interacting elements of a different nature, and the integration of SD with ideas from ABM offers potential to combine the strengths of the two methodologies to solve the problem.

Since knowing the effective role of amidic functions in producing new dye‐stuffs of high thermal fastness and low solubility (e.g. Hostaperm or PV Fast (Hoechst)), great attention has been directed towards the synthesis and use of several dyes and pigments having such moieties. The majority of these dyes are characterized by their tendency to form stable dimers. Sometimes, these dimeric monoazo pigments have the same thermal solvent fastness as disazo pigment dyes of the Cromophtal type (Ciba‐Geigy).

The construction industry is facing challenges because of performance shortfalls. Construction projects are highly complex, distinctive, fragmented and do not have well-established performance assessment models to evaluate their project success. The purpose of this paper is to assess the direction through determination of performance areas that would affect project performance in Indian construction projects.

A survey instrument was developed to gather data on the perception of industry professionals on these identified areas. Purposive sampling method was used to select respondents for the survey. These performance areas are ranked using relative importance index to ascertain a level of importance among the group. Factor analysis (FA) was conducted to identify the significant performance areas project performance. Further to identify the most influence performance areas on Indian construction projects, multiple regression analysis was carried out.

Findings indicated 28 significant performance areas. This shows the low level of adoption of good construction management practices in Indian construction projects. FA resulted in the areas being grouped to nine broad significant performance areas with 59.49% of the total variance, namely, quality, schedule, environment and stakeholder satisfactions, cost, productivity, safety, communication management, customer relations and finance. Multiple regression analysis revealed two pivotal factors “customer relations” and “schedule” that significantly influence project performance in Indian construction industry.

The outcome of the study will guide project stakeholders, who desire to improve project performance on construction projects, to prioritize their efforts. It also highlights performance areas of project management which required more focussed research in the context of Indian construction projects. The findings can be extended to the developing countries.

The purpose of this paper is to model the paths of risks associated with building information modeling (BIM) adoption in the Chinese architecture, engineering and construction industry.

A total of 16 risks were identified from the literature review and grouped into nine categories. The data were collected through a questionnaire survey with 95 professionals in China. The partial least square structural equation modeling was used to analyze the data.

The results suggested the risk categorization was confirmed, and that 15 hypothetical risk paths were statistically significant, which formed 13 chains of risk paths. “Inadequate relevant knowledge and expertise” was the primary root risk category of all the 13 chains of risk paths. Additionally, “technological issues,” “poor information sharing and collaboration,” and “liability for data input” had direct effect on the “cost overrun with BIM,” while all the other risks indirectly influence cost via these three risk categories.

Most of the respondents were designers because few clients and contractors have adopted BIM. In addition, the impact and likelihood of risks were accessed by respondents’ judgment based on their experience, which is a common problem of risk management research. As this study focuses on the Chinese architecture, engineering and construction industry, there would be geographical limitation on the findings.

This study provides practitioners with a clear understanding of the risks associated with BIM adoption and enables practitioners to take measures to mitigate the root risks and assure the potential benefits of BIM.

Although there have been studies on the risks associated with BIM adoption, most of them lacked empirical evidence and failed to examine the interactions between risks. This study is different from these prior studies, because it focuses on the interrelationships between risks and identifies the risk paths and root risks using the empirical data. Therefore, this study expands the literature relating to both BIM and risk management. Also, this study enables practitioners to take measures to mitigate the root risks and assure the potential benefits produced by BIM, thereby contributing to the practice.