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In the analysis of structures in a fire situation by simplified and analytical methods, one assumption is that the fire resistance time is greater than or equal to the required fire resistance time. Among the methodologies involving the fire resistance time, the most used is the tabular method, which associates fire resistance time values to structural elements based on minimum dimensions of the cross section. The tabular method is widely accepted by the technical-scientific community due to the fact that it is safe and practical. However, its main criticism is that it results in lower fire resistance times than advanced thermal and thermostructural analysis methods. The objective of this study was to evaluate the fire resistance time of reinforced concrete beams and compare it with the required fire resistance time recommended by the tabular method of NBR 15200 (ABNT, 2012).

The fire resistance time and required fire resistance time of reinforced concrete beams were evaluated using, respectively, numerical models developed based on the finite element method and the tabular method of NBR 15200 (ABNT, 2012). The influence of the following parameters was investigated: longitudinal reinforcement cover, characteristic compressive strength of concrete, beam height, longitudinal reinforcement area and arrangement of steel bars.

Among the evaluated parameters, the covering of the longitudinal reinforcement proved to be more relevant for the fire resistance time, justifying that the tabular method of NBR 15200 (ABNT, 2012) being strongly and directly influenced by this parameter. In turn, more resistant concretes, higher beams and higher steel grades have lower fire resistance time values. This is because beams in these conditions have greater resistance capacity at room temperature and, consequently, are subject to external stresses of greater magnitude. In some cases, the fire resistance time was even lower than the required fire resistance time prescribed by NBR 15200 (ABNT, 2012). Both the fire resistance time and the required fire resistance time were not influenced by the arrangement of the longitudinal reinforcements.

The present paper innovates by demonstrating the influence of other important design variables on the required fire resistance time of the NBR 15200 (ABNT, 2012). Among several conclusions, it was found that the load level to which the structural elements are subjected considerably affects their fire resistance time. For this reason, it was recommended that the methods for calculating the required fire resistance time consider the load level. In addition, the article quantifies the security degree of the tabular method and exposes some situations for which the tabular method proved to be unsafe. Moreover, in all the models analyzed, the relationship between the span and the vertical deflection associated with the failure of the beams in a fire situation was determined. With this, a span over average deflection relationship was presented in which beams in fire situations fail.

The need to make forecasts is commonplace in industry. The accuracy (and hence, usefulness) of forecasts varies from one sector to another, but is rarely high. Describes an approach to the monitoring of forecasts which aims to detect significant inaccuracy and to quantify the correction(s) that need to be made, based on well‐established methods of SPC, and so it also allows any changes in the pattern of demand to be detected, providing information for the revision of the forecasting model. Since the monitoring technique is based on statistical methods, it provides information which can be used directly in conventional models for inventory management. The user can choose the level of coverage required, and the monitoring technique indicates how well the target is being met. Again, any departure from the required level can be indicated at a stage early enough to take corrective action.

In 1997, the Securities and Exchange Commission (SEC) issued new disclosure rules in an amendment to Regulation S‐X. This release requires the disclosure of both qualitative and quantitative information about market risk by all companies registered with the SEC for annual periods ending after 15 June 1998. Larger companies, with market capitalizations in excess of $2.5 billion, banks, and thrifts were required to apply the regulation’s provisions for annual periods after 15 June 1997. This paper presents results of an analysis of the market risk disclosures by the Dow 30 companies for 1997. The provisions of the amendment requiring the disclosure of qualitative information about market risk by were generally followed by all of the companies contained in the DOW 30. Compliance with the other aspects of the amendment was mixed. These failures might be attributed to confusion over the provisions of the amendment. The results of this study indicate that further evidence is needed on the ability of companies to follow the provisions of the amendment.

The paper discusses the problem of business process modelling, various techniques which are used to carry out business process modelling and aims to analyse the use of different techniques to find a better solution.

Business process modelling techniques could be divided into two groups, the diagrammatic and tabular techniques. As a representative of diagrammatic techniques, a flowchart is chosen and discussed in detail. A process model could also be developed using the activity table as a representative of tabular techniques. A comparative analysis of the two techniques is consequently carried out. The pros and cons of both techniques were analysed on the two case‐studies – the problems of Sales_Claim and Credit_Card are used as examples to test both techniques.

Based on the comparative analysis, several useful remarks are given as a result of this work. First, both techniques are simple and useful for business processes modelling. Drawing a flowchart is easier than developing an activity table. Second, it was found that the flowchart technique is too flexible and does not possess any mechanism to control gaps which could exist in the process model. On the other hand, the vertical linkage mechanism imposes a strict order on the development of the activity table, which enable the analyst to discover gaps existing in the table. Third, it was found that the visibility of a flowchart is good when the model is relatively small, but it becomes unclear in large models. The activity table is more visible even when the table contains hundreds of activities. The visibility depends on the analyst and his/her experience; many analysts prefer a diagrammatic presentation of processes, whereas other analysts are more tabular‐oriented. Fourth, concerning user involvement, the structure of the activity table requires an active user involvement, because every user (internal entity) occupies a certain column in the table, where the entity's activities are indicated. For this reason, the user is interested in cooperating in defining his/her activities correctly. On the other hand, the user's role in creating a flowchart does not go beyond observation. Business process modelling is a complex and difficult task. Using one technique may result in a model that does not reflect the original business process. For this reason, using a combination of both techniques could produce a process model which represents a true reflection of reality. Thus, it is suggested that because of the strict role imposed by vertical linkage, the analyst starts process modelling by developing the activity table and then continues by transforming the table into a flowchart. Having such a flowchart, which represents a good transformation of the original business process, is essential for successful continuation of business process simulation or other methods for business process improvement or reengineering.

The paper summarises and suggests several useful remarks as a result of this work, which also recommends the possibility of linking the two techniques to develop better business process models.

THE bending moments in a strut with lateral loading can usually be found graphically by means of the Polar (Howard) Diagram, but with a strut of non‐uniform section and a complex load system it is difficult to obtain an accurate solution without drawing to an inconveniently large scale. The tabular method described here is applicable to struts of varying section with any load system and involves only arithmetical calculation. The strut is divided into a convenient number of ‘simple’ segments, i.e. segments of uniform section with no point loads applied within the length of each segment, and successive applications are made of relations between the bending moment and slope at either end of the segments. Two trial solutions are necessary, from which the required solution is readily obtained.

The difficulties that MR poses for comparativists were anticipated 40 years ago in Sidney Verba's essay “Some Dilemmas of Comparative Research”, in which he called for a “disciplined configurative approach…based on general rules, but on complicated combinations of them” (Verba, 1967, p. 115). Charles Ragin's (1987) book The Comparative Method eloquently spelled out the mismatch between MR and causal explanation in comparative research. At the most basic level, like most other methods of multivariate statistical analysis MR works by rendering the cases invisible, treating them simply as the source of a set of empirical observations on dependent and independent variables. However, even when scholars embrace the analytical purpose of generalizing about relationships between variables, as opposed to dwelling on specific differences between entities with proper names, the cases of interest in comparative political economy are limited in number and occupy a bounded universe.² They are thus both knowable and manageable. Consequently, retaining named cases in the analysis is an efficient way of conveying information and letting readers evaluate it.³ Moreover, in practice most producers and consumers of comparative political economy are intrinsically interested in specific cases. Why not cater to this interest by keeping our cases visible?

The aim of the research was to investigate the effect of concrete strength on the fire resistance of structures. At first, it may seem contradictory that higher concrete strengths can decrease the fire resistance of building structures. However, if the strength of the concrete exceeds a maximum value, the risk of spalling (the detachment of the concrete surface) significantly.

Prefabricated structural elements are often produced with higher strength. The higher concrete strengths generally do not cause a reduction in the load bearing capacity, but it can have serious consequences in case of structural fire design. Results of two prefabricated elements, namely, one slab (TT shaped panel) and one single layer wall panel, were examined. Results of the specimen with the originally designed composition and a specimen with modified concrete composition were examined, were polymer fibres were added to prevent spalling.

As a result of the experiments, more strict regulations in the standards the author is suggested including more strict regulations in the standards. It has been proved that to ensure the fire safety of the reinforced concrete structures, it is required after polymer fibres even in lower concrete strength class than prescribed by the standard. In addition, during the classification and evaluation of structures, it is advisable to introduce an upper limit of allowed concrete strength for fire safety reasons.

As a result of the experiments, the author suggests including more strict regulations in the standards. It has been proved that to ensure the fire safety of the reinforced concrete structures, it is necessary to require the addition of polymer fibres even in lower concrete strength class than prescribed by the standard. In addition, during the classification and evaluation of structures, it is advisable to introduce an upper limit of allowed concrete strength for fire safety reasons.

The purpose of this study is to alleviate the specified issues to a great extent. To promote patients’ health via early prediction of diseases, knowledge extraction using data mining approaches shows an integral part of e-health system. However, medical databases are highly imbalanced, voluminous, conflicting and complex in nature, and these can lead to erroneous diagnosis of diseases (i.e. detecting class-values of diseases). In literature, numerous standard disease decision support system (DDSS) have been proposed, but most of them are disease specific. Also, they usually suffer from several drawbacks like lack of understandability, incapability of operating rare cases, inefficiency in making quick and correct decision, etc.

Addressing the limitations of the existing systems, the present research introduces a two-step framework for designing a DDSS, in which the first step (data-level optimization) deals in identifying an optimal data-partition (Popt) for each disease data set and then the best training set for Popt in parallel manner. On the other hand, the second step explores a generic predictive model (integrating C4.5 and PRISM learners) over the discovered information for effective diagnosis of disease. The designed model is a generic one (i.e. not disease specific).

The empirical results (in terms of top three measures, namely, accuracy, true positive rate and false positive rate) obtained over 14 benchmark medical data sets (collected from https://archive.ics.uci.edu/ml) demonstrate that the hybrid model outperforms the base learners in almost all cases for initial diagnosis of the diseases. After all, the proposed DDSS may work as an e-doctor to detect diseases.

The model designed in this study is original, and the necessary parallelized methods are implemented in C on Cluster HPC machine (FUJITSU) with total 256 cores (under one Master node).

Prefabricated products are continually entering the building construction market; yet, the decision to use prefabricated products in a construction project is based mostly on personal preferences and the evaluation of direct costs. Researchers and practitioners have debated appropriate measurement systems for evaluating the impacts of prefabricated products and for comparing them with conventional on-site construction practices. The more advanced, cost–benefit approach to evaluating prefabricated products often inspires controversy because it may generate inaccurate results when converting non-monetary effects into costs. As prefabrication may affect multiple organisations and product subsystems, the method used to decide on production methods should consider multiple direct and indirect impacts, including nonmonetary ones. Thus, this study aims to develop a multi-criteria method to evaluate both the monetary and non-monetary impacts of prefabrication solutions to facilitate decision-making on whether to use prefabricated products.

Drawing upon a literature review, this research suggests a multi-criteria method that combines the choosing-by-advantage approach with a cost–benefit analysis. The method was presented for validation in focus group discussions and tested in a case involving a prefabricated bathroom.

The analysis indicates that the method helps a project’s stakeholders communicate about the relative merits of prefabrication and conventional construction while facilitating the final decision of whether to use prefabrication.

This research contributes a method of evaluating the monetary and non-monetary impacts of prefabricated products. The research underlines the need to evaluate the diverse benefits and sacrifices that stakeholder face when considering production methods in construction.

To the Editor. SIR: I should like to make some comments on the article by E. W. Parkes on ‘Linear Simultaneous Equations’ on p. 48 of the February issue. This article does not paint a fair picture of this operation.