PhD forum: extracting similar patterns of behavior with a network of binary sensors

The aging population is continuously growing and this results in increasing the demands for using technologies to help to manage the rapidly growing sector of the elderly population. To contribute in this effort, we propose a method that can find similar patterns of behavior for extended durations. Our method uses motion sensors as a privacy-aware alternative to cameras. We compute three initial parameters to extract similar patterns of behavior: (1) movement in spot; (2) movement between rooms; and (3) movement within rooms. The three parameters demonstrate good similarity indicators for finding patterns of behavior between each pair of days

Discovering human activities from binary data in smart homes

With the rapid development in sensing technology, data mining, and machine learning fields for human health monitoring, it became possible to enable monitoring of personal motion and vital signs in a manner that minimizes the disruption of an individual’s daily routine and assist individuals with difficulties to live independently at home. A primary difficulty that researchers confront is acquiring an adequate amount of labeled data for model training and validation purposes. Therefore, activity discovery handles the problem that activity labels are not available using approaches based on sequence mining and clustering. In this paper, we introduce an unsupervised method for discovering activities from a network of motion detectors in a smart home setting. First, we present an intra-day clustering algorithm to find frequent sequential patterns within a day. As a second step, we present an inter-day clustering algorithm to find the common frequent patterns between days. Furthermore, we refine the patterns to have more compressed and defined cluster characterizations. Finally, we track the occurrences of various regular routines to monitor the functional health in an individual’s patterns and lifestyle. We evaluate our methods on two public data sets captured in real-life settings from two apartments during seven-month and three-month periods

Early detection of corrosion activity in reinforced concrete slab by AE technique

Chloride induced corrosion of steel reinforcement in concrete is the main cause of damage to concrete structures in marine, or structures exposed to de-icing salt environments. The need for early detection of corrosion in reinforced concrete structures is widely acknowledged in corrosion health monitoring for strategic civil engineering projects. This paper summarizes results from a laboratory experiment, using Acoustic Emission (AE) technique, regarding early detection of corrosion in reinforced concrete slabs that are exposed to chloride. The Results showed that while AE was able to determine the initiation of corrosion in reinforced concrete slab, Half-cell potential (HCP) was not able to detect it at the early stage of corrosion

The EFL Essay Writing Difficulties of Egyptian Student Teachers of English: Implications for Essay Writing Curriculum and Instruction

The current study is conducted with the aim of investigating the essay writing difficulties of Egyptian student teachers of English. More specifically, it attempts to fulfil the following three aims: explore the focuses of teaching essay writing at one of the pioneering faculties of education in Egypt; investigate the different essay writing practices used by Egyptian essay writing teachers from teachers as well as their students’ perspectives; and identify the essay writing difficulties encountered by Egyptian student teachers of English at the concerned faculty of education from both students and their teachers’ perspectives. The current study adopts an interpretive methodology that uses a sequential mixed methods approach to data collection and analysis. Therefore, I administered a questionnaire to 165 student teachers of English and 7 essay writing teachers, conducted semi-structured in-depth interviews with 14 student teachers of English and 7 essay writing teachers, and observed nine essay writing sessions of different teachers. Data is analysed quantitatively using SPSS descriptive statistics and qualitatively using exploratory content analysis. Findings of the current study reveal that there are eleven focuses of teaching essay writing at the concerned faculty of education. These focuses have been classified into four main categories: Mechanics/Language, Content, Structure/Layout and Practising Writing. Findings also shed light on the essay writing teachers’ practices in relation to planning, teaching, feedback and assessment. Finally, findings show that student teachers of English encounter the following difficulties in their essay writing: planning difficulties, organisational difficulties including coherence, cohesion, and stylistic difficulties, lexical problems, and technical difficulties including grammar, punctuation, spelling and revision and editing. According to the above mentioned findings, a theoretical writing model has been devised and a pedagogical process genre approach to teaching EFL essay writing in Egypt has been proposed. Implications for essay writing curriculum planning and instruction are also included. Finally, suggestions for further research are provided.The Egyptian Ministry of Higher Educatio

Recycled Waste Tires Management in Constructions

Concrete is one of the most commonly used materials in construction worldwide. Yet the production of concrete from raw materials, such as cementitious materials, water, sand, and natural aggregate, leads to the release of significant amounts of CO2 and greenhouse gases. Therefore, there is a growing interest in producing sustainable concrete using recycled materials. This study will focus on waste management considering the incorporation of recycled tires as a replacement for fine and coarse aggregate in structural concrete. These waste car and truck tires present serious environmental challenges when dumped into landfills as they consume large amounts of space, contaminate the air, soil, and water, and impact human health. The reuse of rubber is therefore inevitable. This study conducts a life cycle cost analysis (LCCA) to compare the cost-effectiveness of a conventional concrete mix (RC1) with a rubberized concrete mix (RC2). Furthermore, to promote the use of eco-friendly materials in concrete mixes, this study suggests the use of seawater as a replacement for freshwater in both the conventional mix and the rubberized concrete mix in order to eliminate the cost and energy consumed during the desalination process. The LCCA results show that the rubberized concrete (RC2), obtained by replacing 5% of aggregate and mixing it with seawater, is more cost-effective than RC1, with a cost savings of 30%.LCCA data were acquired by investigating thirteen concrete mixes (a control mix; 5%, 10%, and 20% rubber aggregate substitutions mixed with freshwater; and 0%, 5%, and 10% rubber aggregate substitutions mixed with seawater). Moreover, the impact of rubber and seawater was evaluated on fresh and hardened concrete characterizations. The results show that as the rubber and seawater contents were increased, the workability, density, and compressive strength were decreased; however, for durability in terms of Rapid Chloride Permeability (RCP) and water absorption, rubberized and seawater concrete mixes outperformed the control mix. Our selection of RC2 for LCCA is based on its good fresh and mechanical characterizations in comparison to the other rubberized concrete mixes. In its approach to its subject, this study is an example of multidisciplinary research, as it synergizes construction management through life cycle cost analysis with construction engineering materials area