Psychological State Prediction using Smartphone Data and Machine Learning

For this thesis, participants had installed an application on their smartphones, the application is called AWARE client v2. This application collects data such as mobility, location, battery, device usage, screen status, weather, etc. Once the data was collected, participants filled out a survey which had statements related to their psychological states. The responses to this survey is the ground truth. There are different categories in the survey, for example, one category is related to depression and anxiety. The responses to the statements in this category can be used to infer the psychological states of participants. For example, for the same category, higher score means the participant is under depression or anxiety. This thesis tries to explore different machine learning models that can be used to predict these responses using the data collected from the smartphone and also tried to explore if any of the features are correlated with these responses. In the past, many studies have used smartphone-based passive sensing technology to capture data that can be correlated to user's mental state. For these studies, the most common features considered include location and mobility, activity, audio signals, battery, device usage, screen usage, calls and SMS. In this thesis, the methods and techniques used to predict the results are discussed and compared. Before that, the description for the features of the dataset and also the description of the ground truth is given in detail. So, the motive here is to find out if these ground truths can be predicted using the data collected from the AWARE-application and which methods and which machine learning models are more suitable for the given dataset. Previous research in this area is used as reference to narrow down list of possible approaches and it is implemented to see if it works for the given dataset and ground truths. Finally, the results are presented for comparison, the problems encountered are discussed and alternative approaches are presented for future scope

Modélisation des transports ioniques dans les milieux poreux saturés : application à la pénétration des chlorures dans les matériaux cimentaires

Dans ce travail, le problème du transport d'espèce ionique à travers les milieux poreux saturés a été documenté. Un modèle unidimensionnel basé sur l’approche multi-espèce est présenté. C'est la nouvelle version d'un modèle précédent, MsDiff, développé il y a quelques années dans notre groupe [TRU 00] qui décrit la diffusion d'espèce ionique avec l'équation de Nernst-Planck. Avec l’approche multi-espèces, il est possible de prendre en compte les interactions qui existent entre les espèces ioniques différentes dans la solution interstitielle du béton. Le schéma numérique du modèle est basé sur la méthode des différences finies avec des techniques de Cranck-Nickolson et de Lax-Wendroff. Afin de faire les simulations avec MsDiff, nous avons besoin des données d'entrée. Plusieurs essais ont été exécutés afin de les acquérire. Des essais standards d'immersion ont été effectués pour valider les résultats de MsDiff avec une attention particulière aux coefficients de diffusion des ions et aux interactions entre les chlorures et la phase solide du matériau. Quelques autres modèles existants ont été également essayés pour la comparaison avec les profils expérimentaux de chlorure. Des expérimentations ont été faites pour observer l'influence de la période d'exposition, de l'âge du béton à l'exposition et de la concentration de la solution environnementale sur la pénétration des chlorures. Enfin, les simulations afin de calculer le temps d’initiation de la corrosion ont été effectuées avec MsDiff en utilisant les données expérimentales déjà obtenues tout en utilisant différents critères adoptés par différents groupes de recherche.\ud Mots Clés : Chlore, pénétration, béton, multi-espèces, modélisation, corrosion\ud \ud \ud Here the problem of ionic species transport through concrete porous media has been documented. Chloride ions penetration in cementitious materials is one of the processes widely responsible for the degradation of concrete structures. Here, a one-dimensional model based on a multi-species approach of the ionic transport is presented. It is the new version of a previous model MsDiff developed a few years ago in our group [TRU 00] that describes the diffusion of ionic species with the Nernst-Planck equation instead of Fick’s laws. With a multi-species approach, it is possible to take into account the interactions existing among different ionic species in pore solution of concrete. The numerical scheme of the model is based on finite difference method with Crank-Nickolson and Law-Wendroff techniques. In order to run MsDiff, we need an input data. Several experiments were performed accordingly to provide experimental feedback to MsDiff. Standard immersion tests were conducted to validate the outcomes of MsDiff. Special attention is given to the diffusion coefficients of the ions and the interactions between the ionic species and the solid phase. In addition to MsDiff, some other existing models were also tried for the sake of comparison with the experimental chloride profiles. Certain experimentation was conducted to watch the effect of exposure period, concrete age at exposure and concentration in the environmental solution. In the end, the simulations were performed with MsDiff in order to calculate the chloride-induced corrosion initiation time using the experimental data already achieved while making use of different criteria adopted by different research groups.\ud \u

Effect of Admixtures on Mechanical Properties of Cementitious Mortar

In the current study, the primary focus is to investigate the effect of Styrene Butadiene Rubber (SBR), silica fume and fly ash on compressive and flexure strengths of cementitious mortar. Three types of specimens are prepared; the first series comprises of control specimen; the second one consists of the mortar’s specimen modified with SBR and the third one consists of the mortar’s specimen modified with SBR in a combination of fly ash and silica fumes. Mortar samples are cast in the weight ratio of 1:2.75 (cement: sand). The SBR is added at a rate of 20% of the mass of cement. The water to cement ratio (W/C) is kept at 0.5 for control specimens and the quantity of mixing water in SBR-containing samples is reduced by the same amount as the SBR is added: The adjustment is meant to obtain same consistency for all the specimens.  20% fly ash and 2.5% silica fume are added to the mortar as replacement of cement. Compressive and flexure tests are carried out according to ASTM standards. Moreover, SEM is also performed on samples at the age of 28 days. Studies reveal that SBR and SCMs reduce the mechanical strength of the mortars. SEM and EDS studies show that SBR hinders the formation of albite, whereas silica content from silica fumes and fly ash converts CaCO3 to Wollastonite (a white loose powder), which is responsible for the reduction of mechanical strength. The study also confirms that the addition of SBR in place of water hinders the formation of primary and secondary hydration products. Doi: 10.28991/cej-2020-03091610 Full Text: PD

An efficient energy management in office using bio-inspired energy optimization algorithms

Energy is one of the valuable resources in this biosphere. However, with the rapid increase of the population and increasing dependency on the daily use of energy due to smart technologies and the Internet of Things (IoT), the existing resources are becoming scarce. Therefore, to have an optimum usage of the existing energy resources on the consumer side, new techniques and algorithms are being discovered and used in the energy optimization process in the smart grid (SG). In SG, because of the possibility of bi-directional power flow and communication between the utility and consumers, an active and optimized energy scheduling technique is essential, which minimizes the end-user electricity bill, reduces the peak-to-average power ratio (PAR) and reduces the frequency of interruptions. Because of the varying nature of the power consumption patterns of consumers, optimized scheduling of energy consumption is a challenging task. For the maximum benefit of both the utility and consumers, to decide whether to store, buy or sale extra energy, such active environmental features must also be taken into consideration. This paper presents two bio-inspired energy optimization techniques; the grasshopper optimization algorithm (GOA) and bacterial foraging algorithm (BFA), for power scheduling in a single office. It is clear from the simulation results that the consumer electricity bill can be reduced by more than 34.69% and 37.47%, while PAR has a reduction of 56.20% and 20.87% with GOA and BFA scheduling, respectively, as compared to unscheduled energy consumption with the day-ahead pricing (DAP) scheme

Development of an Acid Resistant Concrete: A Review

This review paper addresses the measures taken to prevent or minimize the deterioration of concrete, which confronts an acidic environment. Primarily, the mechanism of reaction between alkaline concrete and acid is clearly demonstrated. The mechanism of reaction clearly sets guidelines as to how the chances of this disastrous reaction should be minimized or eliminated at all. The suggested preventive measures are two-fold i.e. the improvement of the basic microstructure of concrete and the provision of barriers against acids. Concrete can be made acid resistant using classical as well as novel techniques like nanotechnology.   There exists an immense need that these measures are recognized and implemented by the construction industry to put a stop to huge money losses

Effect of Phosphorus and Sulfur on the Yield and Nutrients Uptake of Wheat

A field experiment was conducted to study the effect of phosphorus and sulfur on the yield and nutrients uptake of wheat at New Developmental Research Farm (NDF)  Malakandher, University of Agriculture, Peshawar in Rabi season during 2011-2012. The experiment was laid out in randomized complete block design (RCBD) with three replications. Phosphorus was applied  at the rate of 60, 90 and 120 kg ha-1 as DAP where as sulfur was applied at the rate of  45, 60 and 75 kg ha-1 as ammonium sulphat  along with control ( no fertilizer) and a treatment of just N and K  as basal dose (120 + 60 kg ha-1). The results showed that biological yield increased significantly (p≤0.05) over control when P and S were applied at the rate of 90-45 kg ha-1where as significantly higher grain yield was recorded in treatment receiving 120 kg P and 45 kg S along with a basal dose of N and K, Significantly highest straw yield of 4245 kg ha-1 was noted in treatment receiving 90 kg P along with 45 kg S ha-1. The soil samples collected at anthesis stage and post harvest stage showed that the P and S contents were significantly affected and the higher values were noted in plot receiving the maximum level of the respective fertilizer i.e P and S but the trend of increase was not consistent with respect to the amount of P and S applied. The P and S content in leaves indicated that higher level of S (75 kg ha-1) resulted in significantly low uptake of P and vice versa indicating their antagonistic effect with each other. This antagonistic effect was displayed in the yield whereby maximum grain yield was obtained where higher dose of P along with lower level of S was applied.

Evaluation of Concrete with Partial Replacement of Cement by Waste Marble Powder

This study aims to evaluate concrete having Waste Marble Powder (WMP) as partial replacement of cement. Marble is the metamorphic form of limestone (CaCO3) and WMP was chosen as substitute of cement on account of its high calcium oxide content. WMP is by-product of marble industry and is an environmental burden. The manufacturing of cement is also environmentally hazardous owing to emission of greenhouse gases. Thus, the recycling of WMP in place of cement in concrete offers two ecological advantages. Thirdly, WMP has a specific gravity of 2.6 against that of 3.15 for cement, which reduces the weight of the finished products. Based on the previous studies, five different concrete mixes were prepared having 0, 5, 10, 15 and 15% replacement levels. The samples were evaluated both through destructive and non-destructive tests.  Destructive tests included compressive, tensile and flexural strengths, whereas non-destructive tests comprised of ultrasonic pulse velocity (UPV) and rebound hammer. It was observed that the workability decreases with WMP inclusion owing to its higher water absorption, which inhibits lubrication of cement particles. The concrete strength improves up to a replacement level of 10% by mass of cement on account of densification created by the finer WMP and un-hydrated cement particles, which act as hard inclusions. Beyond 10%, the concrete strength starts declining due to insufficient quantity of cement matrix, binding the WMP particles. Schmidt rebound numbers authenticate the compressive strength results: The number increases up to 10% replacement level and beyond 10% it decreases. The results of UPV indicate that the velocity increases with increase in WMP content: The increase is attributed to compactness of the composite with finer WMP particles. Doi: 10.28991/cej-2021-03091637 Full Text: PD

Evaluation of Steel Industrial Slag as Partial Replacement of Cement in Concrete

Cement is the most important ingredient in concrete, which acts as a binding material. It is evaluated that cement is the second largest industrial source of CO2 on earth. This demands a partial or full replacement of cement by an environment-friendly material. In this research industrial waste slag from a local Steel Mill, namely Mangla Metals was selected as possible replacement of cement. Some preliminary standard tests conducted on the slag showed its strong chances to be used as pozzolana. Slag used for this study was reduced to the particle size passing through ASTM standard sieve #100. Concrete specimens containing 10% and 20% replacement of cement by slag were prepared. The mechanical properties like compressive, split cylinder tensile and flexure strength were determined as per standard ASTM methods. Tests were conducted at 3, 7 and 28 days of concrete age. Results show a decrease of 14% in compressive strength, 7.5% in tensile strength and 10.5% in flexure strength for 10% replacement vis-à-vis control specimens at 28 days. For 20% replacement, the decrease in compressive, tensile and flexure strength are 25.5%, 29%, 31% respectively. Additionally, ASTM standard strength activity index test with finer slag particles passing through ASTM sieve #200 provided compressive strength more than that of control specimen. Based on the results, it is concluded that the industrial slag has the potential to partially replace the cement if slag is ground to the particles, passing through ASTM sieve #200. This could lead to a huge reduction of cement quantity in concrete and the environmental burden due to deposition of waste slag in landfills