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The building design processes today are complex, involving many disciplines and issues like collaboration, concurrency and collocation. Several studies have focused on understanding and modeling formal information exchange in these processes. Few past studies have also identified the importance of informal information exchanges in the design process and proposed passive solutions for facilitating this exchange. The purpose of this paper is to term the informal information as ad hoc information and explores if components of ad hoc information exchanges can be actively managed.

An MDM-based framework integrating product, process and people dependencies is proposed and a prototype platform to implement this framework is developed. The demonstration on the usage of this platform to identify information paths during collaboration and hence manage ad hoc information exchanges is presented through an example problem.

Based on the effectiveness of the prototype platform in identifying information paths for design queries, it is concluded that the proposed framework is useful for actively managing some components of ad hoc information exchange.

This research enables the design manager/participants to make a more informed decision on requesting and releasing design information.

Worker activity identification and classification is the most crucial and difficult stage in work sampling studies. Manual methods of recording are tedious and prone to error and, hence automating the task of observing and classifying worker activities is an important step towards improving the current practice. Very recently, accelerometer-based systems have been explored to automate activity recognition in construction, but it had been carried out in controlled environment. The purpose of this paper is to cover the evaluation of the system in field situations.

Experimental investigation was carried out on crews of iron workers and carpenters with accelerometer data loggers worn at selected locations on the human body. The accelerometer data collection was spread over a time period of two weeks, and video recording of the worker activities was concurrently carried out to serve as ground truth, the reference used for comparison. The activity recognition analysis was carried out on accelerometer data features using a decision tree algorithm.

It was found that the classification using the individual training scheme performed better when compared with the collective training scheme for both the trades. The field studies results showed that the classification accuracies for iron work and carpentry are 90.07 and 77.74 per cent, respectively, using decision tree classifier. It was found that similarities of movements were a major cause for lower accuracy of recognition.

The work being preliminary in nature has used the basic classifier and pre-processing methods and, standard settings of algorithms.

The paper has investigated accelerometer-based method for construction labour activity classification in field situations.

This study aims to set out to identify and evaluate potential obstacles to successfully implementing lean construction (LC) as a result.

Several indicators were recognized as major obstacles following an exhaustive assessment of the literature and a multicriteria decision analysis based on the analytic hierarchy process (AHP) of information obtained from a questionnaire survey that was directed to practitioners in the Indian construction industry.

The results of this AHP model suggest that “Managerial” and “Inadequate resources” categories with a priority weight of “0.361” and “0.309” have the highest levels of influence, respectively, while “Inadequate knowledge” and “just in time (JIT)” categories with a priority weight of “0.053” and “0.034” have the lowest levels of influence, respectively.

Construction companies can use the study’s findings as a guide to determine whether they are ready to embrace LC, learn more about the components needed for implementation or investigate any challenges that may arise. These businesses can then create plans to promote the adoption and application of the lean philosophy.

The Indian construction industry may see great success with LC management initiatives. LC concepts have been adopted by many nations, but during the past 20 years, there has only appeared to be a limited amount of lean implementation in the Indian construction industry. It seems that several structural and cultural barriers are preventing its effective implementation. Organizations will not be able to determine what improvement efforts are required, where these efforts should be directed or which initiatives could provide the best outcomes if they are unaware of the elements that influence the effective implementation of LC.

Cyclohexanone-formaldehyde resin (CFR) was in situ modified with tannin (T) in the presence of sodium hydroxide. The purpose of this study is to produce eco-friendly tannin-modified cyclohexanone resins (TCFR) with a one-step method that has higher decomposition temperature than CFR. The solubility, molecular weight and thermal properties of the product were investigated.

Cyclohexanone, formalin (37 per cent aqueous solution) and tannin were mixed and 20 per cent aqueous NaOH solution was added to produce the resin. Tannin has environmentally friendly bio-based phenolic compounds that the tannin structure has been incorporated into the structure of the cyclohexanone formaldehyde resin during the in situ modification of resin, such as resole resin.

The improvement of the properties of the TCFRs produced from condensed tannin. TCFRs were soluble in common organic solvents. The product TCFR has a dark red colour.

The reaction mixture must be stirred continuously. Subsequently, 37 per cent formalin was added drop-wise in total while refluxing. The amount of aqueous NaOH solution of it is limited, as the formed resin may become insoluble in common organic solvents. At the end of the reaction, a water-soluble resin is obtained. Then, the water of water phase was removed from TCFR reaction system, successively by evaporating with rotary evaporator.

This study provides the application of ketonic resins. The TCFR containing tannin groups may also promote the adhesive strength of a coating.

These resins may be used for the preparation of adhesive. Condensed tannin, with a large amount of Catechol groups was considered for reducing the formaldehyde emission level on the adhesive system.

TCFR has been synthesised in the presence of a base catalyst. Environmental and ecological concerns have increased the attention paid by chemical industry to renewable raw materials.

The study aims to review the literatures on the effect of fiber length on the mechanical response of natural fiber composite will help the researchers to know about the perspective of the various natural fibers in making of composite concerning fiber length. The review summarized the work of the other researchers, thereby unambiguously précised suitability of a specific natural fiber for a matrix in use. Thus, one can identify the use of the same fibers–matrix combination to obtain composites with different properties with the control of fiber/matrix interface.

The review work proposes a new kind of diagrammatic representation that expresses the influence of fiber length. This work has not been explored before in this specific format. The chronology of work may help to select natural fibers for use in composites for a specific matrix.

The length of the fiber perception in terms of “critical” length decides the need for pre-treatment process of natural fiber to improve shear stress at the interface for various matrices.

The current review paper attempts to shed light on the association between the fiber length of natural fiber and the mechanical response of natural fiber composite. Moreover, it probes the concepts of critical fiber length as a persuadable factor.

The purpose of this paper is to describe the development of an eco‐friendly tannin‐phenol formaldehyde resin (PFT) applicable in the wood composite industry.

The bark of oak (Quercus castaneifolia) contains a large amount of condensed tannin. Condensed tannin, with a large amount of Catechol groups was considered for reducing the formaldehyde emission level on the adhesive system. Physical characteristics of synthesized PFT resin were evaluated.

For optimal extraction, three solvents were used in the extraction process. The results showed that a mixture of water‐methanol (1:1 v/v) as extracting solvent is the best solvent and yields about 14 per cent tannin based on dry weight of bark. For producing tannin phenol formaldehyde adhesive, 10 per cent, 20 per cent and 30 per cent (based on PF dry weight) of PF, substituted with natural extracted tannin. For evaluating PFT performance effects of percentage amount of substitution tannin content on the gel time, viscosity, pH, and density of adhesives were evaluated. Based on emission test (JIS A 1460‐2001) formaldehyde emission of PFT 10 per cent, 20 per cent and 30 per cent were 1.13, 1.12 and 0.4 mg/100 g, which is very low compared with tannin‐free PF.

Tannin‐PF adhesive compared to PF adhesive had lower PH, higher viscosity and shorter gel time.

The method developed provides a simple and excellent renewable resource “tannin” which can be used or partially substituted in phenol formaldehyde adhesive.

Results showed that replacing PF for tannin reduces modulus of rupture (MOR) and modulus of elasticity (MOE) slightly but has significant effects on IB, water absorption and thickness swelling.

The main objective of the study is to identify the vulnerable areas for river‐line and flash flood hazard and its mitigation through GIS Database Management System (DBMS) of geo‐hydrometeorological parameters. The Dabka watershed constitutes a part of the Kosi Basin in the Lesser Himalaya, India in district Nainital has been selected for the case illustration.

The Dabka DBMS is constituted of three GIS (Geographic Information System) modules, i.e. geo‐informatics (consists of geomorphology, soils, geology and land use pattern, slope analysis, drainage density and drainage frequency), weather informatics (consists of daily, monthly and annual weather data about temperature, rainfall, humidity and evaporation) and hydro‐informatics (consist of runoff, sediment delivery, and denudation). The geo‐informatics and weather informatics modules carried out by comprehensive field work and GIS mapping than both modules used to carry out hydro‐informatics module. Through the integration and superimposing of spatial data and attribute data with their GIS layers of all these modules prepared Flood Hazard Index (FHI) to identify the level of vulnerability for flood hazards and their socio‐economic and environmental risks.

The results suggest that geo‐environmentally most stressed areas of barren land (i.e. river‐beds, flood plain, denudational hills, sites of debris flow, gullies, landslide prone areas etc.) have extreme vulnerability for flood hazard due to high rate of runoff, sediment load delivery and denudation during rainy season (i.e. respectively 84.56 l/s/km², 78.60 t/km² and 1.21 mm/year) whereas in geo‐environmentally least stressed dense forest areas (i.e. oak, pine and mixed forests) have low vulnerability due to low rate of stream runoff, sediment load delivery and denudation (i.e. respectively 20.67 l/s/km², 19.50 t/km² and 0.20 mm/year). The other frazzled geo‐environment which also found high vulnerable for flood hazard and their risks is agricultural land areas due to high rate of stream runoff, sediment load delivery and denudation rates (i.e. respectively 53.15 l/s/km², 90.00 t/km² and 0.92 mm/year).

For hydro‐informatics module it is quite difficult to monitor water and sediment discharge data from each and every stream of the Himalayan terrain due the steep and rugged topography. It requires strategic planning and trained man power as well as sufficient funds; therefore representative micro‐watershed approach of varied ecosystem followed for a three years (2006‐2008) period.

The study will have great scientific relevance in the field of river‐line flood and flash flood hazard and its socio‐economic and environmental risks prevention and management in Himalaya and other mountainous terrain of the world.

This study generated primary data on hydro‐informatics and weather informatics to integrate with geo‐informatics data for flood hazard assessment and mitigation as constitutes a part of multidisciplinary project, Department of Science and Technology (D.S.T.) Government of India.