X-ray radiography and tomography for monitoring the penetration depth of consolidants in Opuka – the building stone of Prague monuments

Stone consolidation is one of the major restoration treatments used for historical monuments preservation. A natural stone is a complicated heterogeneous porous system making the process of consolidation dependent on many variables. In practical restoration aims, for a given stone type, the selection of a suitable consolidant and consolidation conditions therefore remains a complex issue. The impregnation depth is a key factor for the assessment of the treatment efficiency. The combination of state-of-the-art hybrid pixel semiconductor detectors with newly available micro-focus X-ray sources makes possible to apply X-ray radiography, an ideal non-destructive tool, for penetration depth monitoring. In this study, high-resolution X-ray radiography is used for monitoring the penetration depth of organosilicon consolidants in the Opuka stone. The penetration depth has been evaluated in relation to the time of consolidation, stone porosity and consolidation mixtures properties. The exact influence of the X-ray contrast agent on the consolidation depth has been investigated as well. The information obtained provides supplementary knowledge on the suitability of investigated products for the treatment of this type of stone. In our study, the capabilities of X-ray radiography have been demonstrated on X-ray radiography simple projections, high-resolution computed tomography (CT) as well as on the dynamic processes monitoring. The results thus can serve also as an instrumental and methodological example applicable for consolidation monitoring of other stone types.     

Definition of the procedure to determine the suitability and durability of an anti-graffiti product for application on cultural heritage porous materials

Anti-graffiti protection is becoming a common practice in many urban buildings, especially in areas of social decay. When Cultural Heritage objects are affected by graffiti, the application of anti-graffiti products can result not only in an unsatisfactory result but also in an irreversible damage of an invaluable cost. The materials commonly found in these constructions are very frequently porous and present different types of decay forms. For this reason, the protection of these materials should be carefully considered. This paper proposes a criterion to decide on the suitability and durability of an anti-graffiti product prior to its application in a porous surface of a protected building. Performance classifications are defined for a series of properties including colour and gloss, and hydric and durability properties, and minimum acceptable values or reductions in these properties are recommended.     

An incidence survey of battered children in two elementary schools of Seoul

Among the 1,142 girls and boys aged 9 to 11 years, 8.2% were seriously battered, 58% were mildly battered and 33.8% were unbattered during the past year. Child battering was more serious in families in the lower social strata, with poor living conditions, in broken families such as those with stepparents or absent mothers, and where parents were unskilled workers or unemployed. Finally, child battering was closely related to all other forms of family violence.     

Market orientation in managing relationships with multiple constituencies of Croatian higher education

In this paper, market orientation in Croatian higher education (HE) is discussed within the context of stakeholder-oriented management. Drawing on existing studies, the ‘classical’ empirical model, describing the market orientation of generic nonprofit organisations, has been adapted to the contingencies of the Croatian HE sector. Empirical testing of the model, based on primary data drawn from the majority of public institutions of higher learning in the country, reveals inadequate market orientation toward the relevant stakeholders. Although social market orientation currently does not exist in Croatian HE institutions, the empirical results confirm that it might be possible to initiate a ‘virtuous circle’, in which relevant market orientation and stakeholder management practices, directed toward one or other of the stakeholders, simultaneously enhance orientation toward the other stakeholders. Unfortunately, the current situation in HE is not satisfactory, which could hinder the implementation of development of knowledge society in Croatia.

A generic construct based workload model for web search

Benchmarks are vital tools in the performance measurement, evaluation, and comparison of computer hardware and software systems. Standard benchmarks such as the TREC, TPC, SPEC, SAP, Oracle, Microsoft, IBM, Wisconsin, AS³AP, OO1, OO7, XOO7 benchmarks have been used to assess the system performance. These benchmarks are domain-specific and domain-dependent in that they model typical applications and tie to a problem domain. Test results from these benchmarks are estimates of possible system performance for certain pre-determined problem types. When the user domain differs from the standard problem domain or when the application workload is divergent from the standard workload, they do not provide an accurate way to measure the system performance of the user problem domain. System performance of the actual problem domain in terms of data and transactions may vary significantly from the standard benchmarks.In this research, we address the issue of generalization and precision of benchmark workload model for web search technology. The current performance measurement and evaluation method suffers from the rough estimate of system performance which varies widely when the problem domain changes. The performance results provided by the vendors cannot be reproduced nor reused in the real users’ environment. Hence, in this research, we tackle the issue of domain boundness and workload boundness which represents the root of the problem of imprecise, ir-representative, and ir-reproducible performance results. We address the issue by presenting a domain-independent and workload-independent workload model benchmark method which is developed from the perspective of the user requirements and generic constructs. We present a user-driven workload model to develop a benchmark in a process of workload requirements representation, transformation, and generation via the common carrier of generic constructs. We aim to create a more generalized and precise evaluation method which derives test suites from the actual user domain and application setting.The workload model benchmark method comprises three main components. They are a high-level workload specification scheme, a translator of the scheme, and a set of generators to generate the test database and the test suite. They are based on the generic constructs. The specification scheme is used to formalize the workload requirements. The translator is used to transform the specification. The generator is used to produce the test database and the test workload. We determine the generic constructs via the analysis of search methods. The generic constructs form a page model, a query model, and a control model in the workload model development. The page model describes the web page structure. The query model defines the logics to query the web. The control model defines the control variables to set up the experiments.In this study, we have conducted ten baseline research experiments to validate the feasibility and validity of the benchmark method. An experimental prototype is built to execute these experiments. Experimental results demonstrate that the method based on generic constructs and driven by the perspective of user requirements is capable of modeling the standard benchmarks as well as more general benchmark requirements.     

Text classification from unlabeled documents with bootstrapping and feature projection techniques

Many machine learning algorithms have been applied to text classification tasks. In the machine learning paradigm, a general inductive process automatically builds a text classifier by learning, generally known as supervised learning. However, the supervised learning approaches have some problems. The most notable problem is that they require a large number of labeled training documents for accurate learning. While unlabeled documents are easily collected and plentiful, labeled documents are difficultly generated because a labeling task must be done by human developers. In this paper, we propose a new text classification method based on unsupervised or semi-supervised learning. The proposed method launches text classification tasks with only unlabeled documents and the title word of each category for learning, and then it automatically learns text classifier by using bootstrapping and feature projection techniques. The results of experiments showed that the proposed method achieved reasonably useful performance compared to a supervised method. If the proposed method is used in a text classification task, building text classification systems will become significantly faster and less expensive.     

Distributed delay input shaper design by optimizing smooth kernel functions

The aim of this paper is the development of a general class of input shapers with distributed time delay which leads to retarded spectral properties. The design of the shaper is formulated as a multi-objective optimization problem, where response time and robustness, expressed in terms of residual vibrations, are the main objectives. As a part of the optimization formulation, common requirements for input shapers such as non-decreasing step response and unity steady state gain are considered in the design. Moreover, additional optional requirements, such as smoothness of a step response, jerk and even jounce limits can be added to optimization procedure. The resulting problem can be solved using convex optimization techniques. Several illustrative examples are presented in comparison with classical input shaping techniques. Finally, implementation aspects are discussed. The paper is accompanied by an implementation in MATLAB, including a user-friendly interface for the interactive shaper design.     

Integrating alternative learning and assessment in a course of English for law students

Alternative approaches to learning and assessment have become common practice in higher education today. While these approaches have several learning, instructional and assessment advantages for students and teachers, a need exists for a better understanding of their consequential evidence. The purpose of this study was to examine students’ perceptions of, and satisfaction with, the experience of learning English for Law in the environment of a comprehensive learning and assessment system integrating the project component and academic writing portfolio component into the framework of traditional learning. A sample of 58 law majors from Mykolas Romeris University in Vilnius, Lithuania participated in the study. The main findings of the study indicate that the integrated approach to learning English for Law was very well accepted by the students due to the following benefits it presented: (i) this approach is effective and useful in promoting students’ productive and receptive language skills; (ii) it enhances students’ satisfaction with their results; (iii) it fosters one’s motivation to learn a foreign language; (iv) it promotes students’ development as independent learners. It is recommended that this study be extended to the investigation of the impact of such an approach on the students’ final results in ESP in comparable groups.