Search results for: Zakaria Salmi

Authors: Fatima Zohra Zeggai, Benjamin Carbonnier, Aïcha Hachemaoui, Ahmed Yahiaoui, Samia Mahouche-Chergui, Zakaria Salmi

Abstract:

A series of polyaniline (PANI)/modified Montmorillonite (MMT) Clay nanocomposite materials have been successfully prepared by In-Situ polymerization in the presence of modified MMT-Clay or Diazonium-MMT-Clay. The obtained nanocomposites were characterized and compared by various physicochemical techniques. The presence of physicochemical interaction, probably hydrogen bonding, between clay and polyaniline, which was confirmed by FTIR, UV-Vis Spectroscopy. The electrical conductivity of neat PANI and a series of the obtained nanocomposites were also studied by cyclic voltammograms.

Keywords: polyaniline, clay, nanocomposites, in-situ polymerization, polymers conductors, diazonium salt

Procedia PDF Downloads 441

Authors: Zakaria Haddad, Azzedine Nahoui, Mohamed Salmi, Ali Djagham

Abstract:

Solar distillation is an effective and practical method for the production of drinking water in arid and semi-arid areas; however, this production is very limited. The aim of this work is to increase the latter by means of single slope solar still with four glass cover without augmenting volume and surface of a conventional solar still, using local materials and simple design. The equipment was tested under the climatic condition of Msila city (35°70′ N, 4°54′ E), Algeria. Performance of the use of four glass cover was studied, and exhaustive data were collected, analyzed, and presented. To show the effectiveness of the system, its performance was compared with that of the conventional solar still. The experimental study shows that the production of the proposed system achieves 5.3 l/m²/day and 5.8 l/m²/day respectively for the months of April and May, with an increase of 10% and 17% compared to the conventional solar still.

Keywords: drinking water, four glass cover, production, solar distillation

Procedia PDF Downloads 105

Authors: Shahed Vahedi, Mohd Salmi Md Noorani

Abstract:

This paper investigates cluster synchronization phenomena between community networks. We focus on the situation where a variety of dynamics occur in the clusters. In particular, we show that different synchronization states simultaneously occur between the networks. The controller is designed having an adaptive control gain, and theoretical results are derived via Lyapunov stability. Simulations on well-known dynamical systems are provided to elucidate our results.

Keywords: cluster synchronization, adaptive control, community network, simulation

Procedia PDF Downloads 451

Authors: R. Pääkkönen, L. Korpinen, T. Kava, I. Salmi

Abstract:

This study evaluates obstructive sleep apnea treatment through a case study involving a 67-year-old male driver who had a successful continuous positive airway pressure (CPAP) treatment at home but experienced difficulties with traveling and dental care. There are many cheap sleep apnea and snoring devices available, but there is little professional advice on what kind of devices can help. Professional drivers receive yearly specialized medical care follow-up.

Keywords: sleep, apnea patient, CPAP, professional driver

Procedia PDF Downloads 175

Authors: L. Korpinen, T. Kava, I. Salmi

Abstract:

This study aimed to describe the operating model of obstructive sleep apnea. Due to the large number of patients, the role of nurses in the diagnosis and treatment of sleep apnea was important. Pulmonary physicians met only a minority of the patients. The sleep apnea study in 2018 included about 800 patients, of which about 28% were normal and 180 patients were classified as severe (apnea-hypopnea index [AHI] over 30). The operating model has proven to be workable and appropriate. The patients understand well that they may not be referred to a pulmonary doctor. However, specialized medical follow-up on professional drivers continues every year.

Keywords: sleep, apnea patient, operating model, hospital

Procedia PDF Downloads 102

Authors: Fahad Alsharari, Mohd Salmi Md. Noorani

Abstract:

A Motzkin shift is a mathematical model for constraints on genetic sequences. In terms of the theory of symbolic dynamics, the Motzkin shift is nonsofic, and therefore, we cannot use the Perron-Frobenius theory to calculate its topological entropy. The Motzkin shift M(M,N) which comes from language theory, is defined to be the shift system over an alphabet A that consists of N negative symbols, N positive symbols and M neutral symbols. For an x in the full shift AZ, x is in M(M,N) if and only if every finite block appearing in x has a non-zero reduced form. Therefore, the constraint for x cannot be bounded in length. K. Inoue has shown that the entropy of the Motzkin shift M(M,N) is log(M + N + 1). In this paper, we find a new method of calculating the topological entropy of the Motzkin shift M(M,N) without any measure theoretical discussion.

Keywords: entropy, Motzkin shift, mathematical model, theory

Procedia PDF Downloads 433

Authors: Obaid AlOtaibi, Salman Hussain

Abstract:

Wind energy is associated with many geographical factors including wind speed, climate change, surface topography, environmental impacts, and several economic factors, most notably the advancement of wind technology and energy prices. It is the fastest-growing and least economically expensive method for generating electricity. Wind energy generation is directly related to the characteristics of spatial wind. Therefore, the feasibility study for the wind energy conversion system is based on the value of the energy obtained relative to the initial investment and the cost of operation and maintenance. In Kuwait, wind energy is an appropriate choice as a source of energy generation. It can be used in groundwater extraction in agricultural areas such as Al-Abdali in the north and Al-Wafra in the south, or in fresh and brackish groundwater fields or remote and isolated locations such as border areas and projects away from conventional power electricity services, to take advantage of alternative energy, reduce pollutants, and reduce energy production costs. The study covers the State of Kuwait with an exception of metropolitan area. Climatic data were attained through the readings of eight distributed monitoring stations affiliated with Kuwait Institute for Scientific Research (KISR). The data were used to assess the daily, monthly, quarterly, and annual available wind energy accessible for utilization. The researchers applied the Suitability Model to analyze the study by using the ArcGIS program. It is a model of spatial analysis that compares more than one location based on grading weights to choose the most suitable one. The study criteria are: the average annual wind speed, land use, topography of land, distance from the main road networks, urban areas. According to the previous criteria, the four proposed locations to establish wind farm projects are selected based on the weights of the degree of suitability (excellent, good, average, and poor). The percentage of areas that represents the most suitable locations with an excellent rank (4) is 8% of Kuwait’s area. It is relatively distributed as follows: Al-Shqaya, Al-Dabdeba, Al-Salmi (5.22%), Al-Abdali (1.22%), Umm al-Hayman (0.70%), North Wafra and Al-Shaqeeq (0.86%). The study recommends to decision-makers to consider the proposed location (No.1), (Al-Shqaya, Al-Dabdaba, and Al-Salmi) as the most suitable location for future development of wind farms in Kuwait, this location is economically feasible.

Keywords: Kuwait, renewable energy, spatial analysis, wind energy

Procedia PDF Downloads 105

Authors: Mohd Salmi Md Noorani, Ghada Al-Mahbashi, Sakhinah Abu Bakar

Abstract:

This paper investigates projective lag synchronization (PLS) behavior in drive response dynamical networks (DRDNs) model with identical nodes. A hybrid feedback control method is designed to achieve the PLS with mismatch and without mismatch terms. The stability of the error dynamics is proven theoretically using the Lyapunov stability theory. Finally, analytical results show that the states of the dynamical network with non-delayed coupling can be asymptotically synchronized onto a desired scaling factor under the designed controller. Moreover, the numerical simulations results demonstrate the validity of the proposed method.

Keywords: drive-response dynamical network, projective lag synchronization, hybrid feedback control, stability theory

Procedia PDF Downloads 364

Authors: Nassim Salmi

Abstract:

Postoperative mobilization is an important part of fundamental care. Increased mobilization has a positive effect on recovery, but immobilization is still a challenge in postoperative care. Aims: To report how the establishment of a national nursing database was used to measure postoperative mobilization in patients undergoing surgery for ovarian cancer. Mobilization was defined as at least 3 hours out of bed on postoperative day 1, with the goal set at achieving this in 60% of patients. Clinical nurses on 4400 patients with ovarian cancer performed data entry. Findings: 46.7% of patients met the goal for mobilization on the first postoperative day, but variations in duration and type of mobilization were observed. Of those mobilized, 51.8% had been walking in the hallway. A national nursing database creates opportunities to optimize fundamental care. By comparing nursing data with oncological, surgical, and pathology data, it became possible to study mobilization in relation to cancer stage, comorbidity, treatment, and extent of surgery.

Keywords: postoperative care, gynecology, nursing documentation, database

Procedia PDF Downloads 84

Authors: Salmi-Laouar Sihem, Aouissi Riadh

Abstract:

The Cenomanian formations of the Bellezma-Batna Range are yielding very diversified fossiliferous beds. Among the abundant and well-preserved fossils stands out Aspidiscus cristatus (Lamarck). This taxon is assigned to the Family Latomeandridae (Alloiteau) for the presence of six symmetry axes. The outer morphology of sampled specimens documents a low-energy environment with a high sedimentary rate and a mud-supported bottom. Its provincialism evidences some characteristic thermal gradients of the marked Tethysian climatic areas. Biometric measurements are given. Coral size increases from the North towards the southeastern Tethysian margin where waters are supposed warmer; this feature is also underlined by a frequent bio-erosion of sampled specimens. Its limited stratigraphic range makes it a good candidate for an index species for the Middle Cenomanian.

Keywords: Aspidiscus cristatus, coral, Middle Cenomanian, Batna, Bellezma, Algeria

Procedia PDF Downloads 143

Authors: Salmi-laouar Sihem, Kara Ahmed Imad

Abstract:

The ichnological study of the Djebel BouarifCenomaniandeposits(Northern Aurès Range, Algeria) revealed relatively abundant and diverse sclerobiont communities that are preserved in corals, bivalves, and gastropods ; all are described herein. Fossil traces are dominated by exceptionally preserved Gastrochaenolitesoften with tracemakers (bivalves), which are preserved in situ, Entobia, and Maeandropolydora. Other borings are rare and are represented by a single specimen of Rogerella, Nihilichnus, and Spirolites. Amongsclerozoans, encrustingjuvenile oysters, and non-oyster bivalves (Pseudolimea?granulata) are the mostabundant groups. Otherepibionts, such as gastropods and polychaetes (Glomerulaserpentina), are lesscommon; dwarfgastropods were located on a single oyster Costagyraolisiponensis, whereas Glomerula specimens were clustered on the lower and upper surfaces of coral Aspidiscuscristatus. Gastrochaenoliteswith original tracemakers and all the epibionts studied herein have not been described from the Djebel BouarifCenomaniandeposits to date. The rare occurrences of Spirolites and Nihilichnus are reported from Algeria for the first time.

Keywords: bioerosion, sclerobionts, upper creataceous, southern tethys, atlasic domain

Procedia PDF Downloads 82

Authors: Nor Zila Abd Hamid, Mohd Salmi M. Noorani

Abstract:

This study is focused on the development of prediction models of the Ozone concentration time series. Prediction model is built based on chaotic approach. Firstly, the chaotic nature of the time series is detected by means of phase space plot and the Cao method. Then, the prediction model is built and the local linear approximation method is used for the forecasting purposes. Traditional prediction of autoregressive linear model is also built. Moreover, an improvement in local linear approximation method is also performed. Prediction models are applied to the hourly ozone time series observed at the benchmark station in Malaysia. Comparison of all models through the calculation of mean absolute error, root mean squared error and correlation coefficient shows that the one with improved prediction method is the best. Thus, chaotic approach is a good approach to be used to develop a prediction model for the Ozone concentration time series.

Keywords: chaotic approach, phase space, Cao method, local linear approximation method

Procedia PDF Downloads 301

Authors: Nursuhaila Ibrahim, Noor Hanim Rahmat, Nurul Ain Hasni, Nursyuhada Zakaria

Abstract:

Past studies have shown that class discussions in the ESL classrooms not only helped students exchange ideas with their peers. Students also learn turn taking skills throughout the discussion. Through interacting with their peers, learners learn to use turn-taking strategies. They learn to wait for their turn, to listen to the ideas of others, to disagree, or to agree, and to add on more points in the conversation. This quantitative research explores students’ perception on class discussions and how the discussions influence their choice of turn-taking strategies. Findings of this research will have interesting implications towards the use of class discussions in the ESL classrooms.

Keywords: ESL, class discussions, turn-taking skills, peers

Procedia PDF Downloads 462

Authors: S. Balubaid, M. Z. Abd Majid, R. Zakaria

Abstract:

Energy efficiency is one of the most important issues for green buildings and their sustainability. This is not only due to the environmental impacts, but also because of significantly high energy cost. The aim of this study is to identify the potential actions required for toll plaza that lead to energy reduction. The data were obtained through set of questionnaire and interviewing targeted respondents, including the employees at toll plaza, and architects and engineers who are directly involved in design of highway projects. The data was analyzed using descriptive statistics analysis method. The findings of this study are the critical elements that influence the energy usage and factors that lead to energy wastage. Finally, potential actions are recommended to reduce energy consumption in toll plazas.

Keywords: energy efficiency, toll plaza, energy consumption

Procedia PDF Downloads 505

Authors: M. Z. Shazana, R. Rosazley, M. A. Izzati, A. W. Fareezal, I. Rushdan, A. B. Suriani, S. Zakaria

Abstract:

There is an increasing interest in the development of flexible energy storage for application of Carbon Nanotubes and nanofibrillated cellulose (NFC). In this study, nanocomposite is consisting of Carbon Nanotube (CNT) mixed with suspension of nanofibrillated cellulose (NFC) from Oil Palm Empty Fruit Bunch (OPEFB). The use of Carbon Nanotube (CNT) as additive nanocomposite was improved the conductivity and mechanical properties of nanocomposite from nanofibrillated cellulose (NFC). The nanocomposite were characterized for electrical conductivity and mechanical properties in uniaxial tension, which were tensile to measure the bond of fibers in nanocomposite. The processing route is environmental friendly which leads to well-mixed structures and good results as well.

Keywords: carbon nanotube (CNT), nanofibrillated cellulose (NFC), mechanical properties, electrical conductivity

Procedia PDF Downloads 301

Authors: Zakaria Elkhwesky, Islam E. Salem, Mona Barakat

Abstract:

The purpose of this study is to analyze the importance of disability management practices (DMPs) and the level of implementation from viewpoints of food and beverage (F & B) managers, F and B entry-level employees, working in F & B departments, and human resources (HRs) managers in five-star hotels in Egypt. It also examined the moderating effect of team orientation (TO) between the importance and the implementation. Data were collected from 400 participants. The correlation proved to be significant, moderate, and positive between the importance and the implementation of DMPs. More, the findings revealed that the relationship between the importance and the implementation is significantly more positive under the condition of a high encouragement of TO.

Keywords: disability management practices, diversity management, team orientation, HR management, hospitality, and tourism operations

Procedia PDF Downloads 98

Authors: Ibnorachid Zakaria, El Bikri Khalid, Benamar Rhali, Farah Abdoun

Abstract:

The aim of the present work is to study the linear free symmetric vibration of three-layer sandwich beam using the energy method. The zigzag model is used to describe the displacement field. The theoretical model is based on the top and bottom layers behave like Euler-Bernoulli beams while the core layer like a Timoshenko beam. Based on Hamilton’s principle, the governing equation of motion sandwich beam is obtained in order to calculate the linear frequency parameters for a clamped-clamped and simple supported-simple-supported beams. The effects of material properties and geometric parameters on the natural frequencies are also investigated.

Keywords: linear vibration, sandwich, shear deformation, Timoshenko zig-zag model

Procedia PDF Downloads 446

Authors: Sihem Salmi Laouar, Khoudair Chabane, Rabah Laouar, Adrian J. Boyce et Anthony E. Fallick

Abstract:

The solid mass of Essouabaa belongs paléogéography to the field téthysian and belonged to the area of the Mounts of Mellègue. This area was not saved by the oceanic-2 event anoxic (EAO-2) which was announced, over one short period, around the limit cénomanian-turonian. In the solid mass of Essouabba, the dominant sediments, pertaining to this period, are generally fine, dark, laminated and sometimes rolled deposits. They contain a rather rich planktonic microfaune, pyrite, and grains of phosphate, thus translating an environment rather deep and reducing rather deep and reducing. For targeting well the passage Cénomanian-Turonian (C-T) in the solid mass of Essouabaa, of the studies lithological and biostratigraphic were combined with the data of the isotopic analyses carbon and oxygen like with the contents of CaCO3. The got results indicate that this passage is marked by a biological event translated by the appearance of the "filaments" like by a positive excursion of the δ13C and δ18O. The cénomanian-turonian passage in the solid mass of Essouabaa represents a good example where during the oceanic event anoxic a facies with organic matter with contents of COT which can reach 1.36%. C E massive presents biostratigraphic and isotopic similarities with those obtained as well in the areas bordering (ex: Tunisia and Morocco) that throughout the world.

Keywords: limit cénomanian-turonian (C-T), COT, filaments, event anoxic 2 (EAO-2), stable isotopes, mounts of Mellègue, Algeria

Procedia PDF Downloads 488

Authors: Ibnorachid Zakaria, El Bikri Khalid, Benamar Rhali, Farah Abdoun

Abstract:

The aim of the present work is to study the linear free symmetric vibration of three-layer sandwich beam using the energy method. The zigzag model is used to describe the displacement field. The theoretical model is based on the top and bottom layers behave like Euler-Bernoulli beams while the core layer like a Timoshenko beam. Based on Hamilton’s principle, the governing equation of motion sandwich beam is obtained in order to calculate the linear frequency parameters for a clamped-clamped and simple supported-simple-supported beams. The effects of material properties and geometric parameters on the natural frequencies are also investigated.

Keywords: linear vibration, sandwich, shear deformation, Timoshenko zig-zag model

Procedia PDF Downloads 444

Authors: Y. T. Boon, M. N. Naim, R. Zakaria, N. F. Abu Bakar, N. Ahmad, I. W. Lenggoro

Abstract:

In this study, encapsulation of agarwood oil with non-ionic surfactant, Tween 80 was prepared at critical micelle concentration of 0.0167 % v/v to produce the most stable nano-emulsion in aqueous. The encapsulation has minimized the bioactive compounds degradation in various pH conditions thus prolong their shelf life and maintained its initial oil grade. The oil grading of the prepared samples were conducted using the gel electrophoresis instead of using common analytical industrial grading such as gas chromatography- mass spectrometry (GC- MS). The grading method was chosen due to their unique zeta potential value after the encapsulation process. This paper demonstrates the feasibility of applying the electrophoresis principles to separate the encapsulated agarwood oil or grading of the emulsified agarwood oil. The results indicated that the grading process are potential to be further investigate based on their droplet size and zeta potential value at various pH condition when the droplet were migrate through polyacrylamide gel.

Keywords: electrophoretic mobility, essential oil, nanoemulsion, polyacrylamide gel electrophoresis, tween 80, zeta potential

Procedia PDF Downloads 349

Authors: Muhammad Syahir Aminuddin, Zakaria Man, Mohamad Azmi Bustam Khalil

Abstract:

In order to identify the best possible reaction media for performing H₂S conversion, a total number of 300 different ILs from a combination of 20 cations and 15 anions were screened via COSMO-RS model simulations. By COSMO-RS method, thermodynamic and physicochemical properties of 300 ILs, such as Henry's law constants, activity coefficient, selectivity, capacity, and performance index, are obtained and analyzed. Thus, by comparing the performance of ILs via COSMO-RS, a series of TSILs containing cation of [P66614] with metal chloride anions such as Fe, Ga, and Al were chosen and selected for synthesis based on their performance predicted by COSMO-RS and their economic values. Consequently, the physiochemical properties such as density, viscosity, thermal properties, as well as H₂S absorptive oxidation performances in those TSILs will be systematically investigated.

Keywords: conversion of hydrogen sulfide, hydrogen sulfide, H₂S, sour natural gas, task specific ionic liquids

Procedia PDF Downloads 121

Authors: Bacha Zakaria

Abstract:

This study aimed to investigate the reality of humane treatment and work environment problems for nurses in public hospitals and their repercussions on the patients arriving there. In this curve, our field study was based on a sample of nurses in Algiers hospitals estimated at 100 nurses. The questionnaire prepared by the two researchers was applied face to face with the nurses, and after obtaining and analyzing the data, we concluded the most important results: The presence of many problems in the work environment, such as work pressures, lack of appreciation, verbal and physical violence, risk of infection, poor salary and incentives, working during fatigue, administrative problems etc. And accordingly, The embodiment of humane dealing with patients requires providing a humane work environment for nurses and dealing with them humanely so that they embody positive behaviors while dealing with patients.

Keywords: nursing, future, family-focused care, health equity

Procedia PDF Downloads 60

Authors: Nassim Salmi

Abstract:

This study aimed to identify the administrative, social, cultural, economic and psychological challenges facing the nursing s ector in the Tebessa Algeria. It also seeks to identify whether there are differences between the opinions of managers in public and private hospitals about these challenges. To achieve the objectives of the study, the descriptive analytical method was adopted. The study also used the questionnaire as a tool for collecting the necessary data and information, which was applied to a sample of directors of public and private hospitals in the Tebessa, which amounted to (114) individuals. The study reached a set of results, including: that there are no statistically significant differences between the opinions of managers in public and private hospitals about the administrative, social, cultural, economic and psychological challenges facing the nursing sector in the Tebessa . The results also showed agreement between the views of managers in private public hospitals that the most important administrative challenges are the lack of training programs that affect the efficiency and performance of nursing work, and that the most important social and cultural challenges are the hospital’s failure to provide suitable nurseries for Saudi female nurses, and that the most important economic challenges are the lack of Availability of medical equipment and devices, and the most important psychological challenge is the tense relationship between the administration and the hospital's nursing staff. The study recommended focusing on the importance of rehabilitation and training together, activating the role of training in the ministry and making it compulsory and a condition of renewal for practicing and continuing the nursing profession, and providing the social and economic needs of the nursing staff.

Keywords: postoperative care, gynecology, nursing documentation, database

Procedia PDF Downloads 58

Authors: U. A. Asli, H. Hamid, Z. A. Zakaria, A. N. Sadikin, R. Rasit

Abstract:

This study investigated the effect of a dilute acid, lime and ammonia aqueous pretreatment on the fermentable sugars conversion from empty fruit bunch (EFB) biomass. The dilute acid treatment was carried out in an autoclave, at 121ºC with 4 % of sulphuric acid. In the lime pretreatment, 3 wt % of calcium hydroxide was used, whereas the third method was done by soaking EFB with 28 % ammonia solution. Then the EFB biomass was subjected to a two-stage-acid hydrolysis process. Subsequently, the hydrolysate was fermented by using instant baker’s yeast to produce bioethanol. The highest glucose yield was 890 mg/g of biomass, obtained from the sample which underwent lime pretreatment. The highest bioethanol yield of 6.1mg/g of glucose was achieved from acid pretreatment. This showed that the acid pretreatment gave the most fermentable sugars compared to the other two pretreatments.

Keywords: bioethanol, biomass, empty fruit bunch (EFB), fermentable sugars

Procedia PDF Downloads 574

Authors: Yousra Zakaria Ahmed, Ahmed El Gendy, Salah El Haggar

Abstract:

In this paper, our methodology to assess sustainability of wastewater treatment technologies in Egypt is presented. The preliminary list of factors to be considered, as well as their ranking listed. The factors include, but are not limited to pollutants removal efficiency and energy consumption under the environmental dimension, construction cost, operation and maintenance costs and required land area cost under the economic dimension and public acceptance, noise and generating job opportunities for local residents. This methodology is intended to be a user-friendly screening tool to support the decision making process when investigating different wastewater treatment technologies in Egypt. Based on the research work results presented in this paper, it can be generally concluded that the categorization of some of the social and environmental aspects of sustainability is subjective and highly dependent on the local conditions and researchers’ background.

Keywords: sustainability, wastewater treatment, sustainability assessment, Egypt

Procedia PDF Downloads 466

Authors: Kenza Maher, Yahya Zakaria, Noora S. Al-Jaidah

Abstract:

Temperature is a critical parameter for lithium-ion battery performance, life, and safety. In this study, four commercially available 18650 lithium-ion cells from four different manufacturers are subjected to accelerated cycle aging for up to 500 cycles at two different temperatures (25°C and 45°C). The cells are also calendar-aged at the same temperatures in both charged and discharged states for 6 months to investigate the effect of aging and temperature on capacity fade and state of health. The results showed that all battery cells demonstrated good cyclability and had a good state of health at both temperatures. However, the capacity loss and state of health of these cells are found to be dependent on the cell chemistry and aging conditions, including temperature. Specifically, the capacity loss is found to be higher at the higher aging temperature, indicating the significant impact of temperature on the aging of lithium-ion batteries.

Keywords: lithium-ion battery, aging mechanisms, cycle aging, calendar aging.

Procedia PDF Downloads 67

Authors: Zakaria S. G. Hegazy, Walid M. A. Ahmed

Abstract:

This paper examines the dependence structure of Islamic stock markets on Bitcoin’s realized volatility components in bear, normal, and bull market periods. A quantile regression approach is employed, after adjusting raw returns with respect to a broad set of relevant global factors and accounting for structural breaks in the data. The results reveal that upside volatility tends to exert negative influences on Islamic developed-market returns more in bear than in bull market conditions, while downside volatility positively affects returns during bear and bull conditions. For emerging markets, we find that the upside (downside) component exerts lagged negative (positive) effects on returns in bear (all) market regimes. By and large, the dependence structures turn out to be asymmetric. Our evidence provides essential implications for investors.

Keywords: cryptocurrency markets, bitcoin, realized volatility measures, asymmetry, quantile regression

Procedia PDF Downloads 154

Authors: Zakaria Aketouane, Mustapha Malha, Abdellah Bah, Omar Ansari, Mohamed Asbik

Abstract:

The present paper deals with the thermal performance of a hollow-brick filled with Phase Change Material (PCM). The main objective is to study the effect of percentage and melting temperature of the PCM on the thermal inertia and internal surface temperature of the hollow-brick. A numerical model based on the heat transfer equation and the apparent heat capacity method has been validated using experimental study from the literature. The results show that increasing the percentage of the PCM has a significant effect on time lag and decrement factor that define the thermal inertia; the internal temperature is reduced by 1.36°C to 5.39°C for a percentage from 11% to 71% in comparison to a brick without PCM. In addition, an appropriate melting temperature of 37°C has been deduced for the horizontal wall orientation in Rabat in comparison to 27°C and 47°C.

Keywords: appropriate melting temperature, decrement factor, phase change material, thermal inertia, time lag

Procedia PDF Downloads 207

Authors: Rebiahi Sid Ahmed, Boutarfi Zakaria, Rahmoun Malika, Antonio Galvez

Abstract:

The objective of this study was to explore the possible correlation between resistance to antibiotics and tolerance to biocides in Gram-negative bacilli isolated from the University Hospital Center of Tlemcen. This study focused on 175 clinical isolates of Gram-negative bacilli, it is a question of exploring: their level and profile of resistance to antibiotics, their tolerance to biocides, as well as the identification of the genetic supports of this resistance. Enterobacter spp. was the most predominant bacterial genus, all isolates harbored at least one of the studied genes with significant resistance capacity. Our results show, in some cases, a possible positive correlation between the presence of biocide tolerance genes and those of antibiotic resistance; in fact, tolerance to biocides could be one of the co-selection factors for antibiotic resistance. The results of this study should encourage the good practice of hygiene measures as well as the rational use of antimicrobials in order to hinder the development and emergence of resistance in our hospital departments.Mots clés : Antibiotiques, Biocides, Enterobacter, Hôpital, Résistance,

Keywords: antibiotic, biocides, enterobacter, hospital, resistance

Procedia PDF Downloads 85

Authors: Rosida A. Razak, Mohamad Shanudin Zakaria

Abstract:

The fundamental issues in ICT Governance (ICTG) implementation for Malaysian Public Sector (MPS) is how ICT be applied to support improvements in productivity, management effectiveness and the quality of services offered to its citizens. Our main concern is to develop and adopt a common definition and framework to illustrate how ICTG can be used to better align ICT with government’s operations and strategic focus. In particular, we want to identify and categorize factors that drive a successful ICTG process. This paper presents the results of an exploratory study to identify, validate and refine such Critical Success Factors (CSFs) and confirmed seven CSFs and nineteen sub-factors as influential factors that fit MPS after further validated and refined. The Delphi method applied in validation and refining process before being endorsed as appropriate for MPS. The identified CSFs reflect the focus areas that need to be considered strategically to strengthen ICT Governance implementation and ensure business success.

Keywords: IT governance, critical success factors, productivity, CSFs

Procedia PDF Downloads 249