Search results for: active periods

Authors: Birs Isabela, Muresan Cristina, Folea Silviu, Prodan Ovidiu

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The wing is one of the most important parts of an airplane because it ensures stability, sustenance and maneuverability of the airplane. Because of its shape, the airplane wing can be simplified to a smart beam. Active vibration suppression is realized using piezoelectric actuators that are mounted on the surface of the beam. This work presents a tuning procedure of fractional order controllers based on a graphical approach of the frequency domain representation. The efficacy of the method is proven by practically testing the controller on a laboratory scale experimental stand.

Keywords: fractional order control, piezoelectric actuators, smart beam, vibration suppression

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Authors: Mohammad Rahmani Rezaiyeh, Mojtaba Rahmani Rezaiyeh, Mehrdad Rahmani Rezaiyeh

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Smart speed bump is a new invention and I am invented it. Smart speed bump is a system that can change the position of speed bumps either active or passive in necessary situations. The basic system of smart speed bumps is based on a robotic system which includes mechanic, electronic and artificial intelligence. The smart speed bump is capable of smart decision making and can change its position by anticipating the peak of terrific hours. It can be noted to the advantages of this system such as preventing the waste of petrol while crossing speed bumps, traffic management, accelerating, flowing and securing traffic, reducing accidents and judicial records.

Keywords: invention, smart, robotic system, speed bump, traffic, management

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Authors: Caglayan Pinar Demirtas, Mustafa Koc

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Objective: This study was carried out in order to find out; the methods which are used by primary school teachers to cope with stress, their psychological health, and the direction of controlling focus. The study was carried out by using the ‘school survey’ and ‘society survey’ methods. Method: The study included primary school teachers. The study group was made up of 1066 people; 511 women and 555 men who accepted volunteerly to complete; ‘the inventory for collecting data, ‘the Scale for Attitude of Overcoming Stress’ (SBTE / SAOS), ‘Rotter’s Scale for the Focus of Inner- Outer Control’ (RİDKOÖ / RSFIOC), and ‘the Symptom Checking List’ (SCL- 90). The data was collected by using ‘the Scale for Attitude of Overcoming Stress’, ‘the Scale for the Focus of Inner- Outer Control’, ‘the Symptom Checking List’, and a personal information form developed by the researcher. SPSS for Windows packet programme was used. Result: The age variable is a factor in interpersonal sensitivity, depression, anxciety, hostality symptoms but it is not a factor in the other symptoms. The variable, gender, is a factor in emotional practical escaping overcoming method but it is not a factor in the other overcoming methods. Namely, it has been found out that, women use emotional practical escaping overcoming method more than men. Marital status is a factor in methods of overcoming stress such as trusting in religion, emotional practical escaping and biochemical escaping while it is not a factor in the other methods. Namely, it has been found out that married teachers use trusting in religion method, and emotional practical escaping method more than single ones. Single teachers generally use biochemical escaping method. In primary school teachers’ direction of controlling focus, gender variable is a factor. It has been found out that women are more inner controlled while the men are more outer controlled. The variable, time of service, is a factor in the direction of controlling focus; that is, teachers with 1-5 years of service time are more inner controlled compared with teachers with 16-20 years of service time. The variable, age, is a factor in the direction of controlling focus; that is, teachers in 26-30 age groups are more outer controlled compared with the other age groups and again teachers in 26-30 age group are more inner controlled when compared with the other age groups. Direction of controlling focus is a factor in the primary school teachers’ psychological health. Namely, being outer controlled is a factor but being inner controlled is not. The methods; trusting in religion, active plannıng and biochemical escaping used by primary school teachers to cope with stress act as factors in the direction of controlling focus but not in the others. Namely, it has been found out that outer controlled teachers prefer the methods of trusting in religion and active planning while the inner controlled ones prefer biochemical escaping.

Keywords: coping with, controlling focus, psychological health, stress

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Authors: Isaac Mugume

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Since the beginning of the 21st century, climate change has been an issue due to the reported rise in global temperature and changes in the frequency as well as severity of extreme weather and climatic events. The changing climate has been attributed to rising concentrations of greenhouse gases, including environmental changes such as ecosystems and land-uses. Climatic projections have been carried out under the auspices of the intergovernmental panel on climate change where a couple of models have been run to inform us about the likelihood of future climates. Since one of the major forcings informing the changing climate is emission of greenhouse gases, different scenarios have been proposed and future climates for different periods presented. The global climate models project different areas to experience different impacts. While regional modeling is being carried out for high impact studies, bias correction is less documented. Yet, the regional climate models suffer bias which introduces uncertainty. This is addressed in this study by bias correcting the regional models. This study uses the Weather Research and Forecasting model under different representative concentration pathways and correcting the products of these models using observed climatic data. This study notes that bias correction (e.g., the running-mean bias correction; the best easy systematic estimator method; the simple linear regression method, nearest neighborhood, weighted mean) improves the climatic projection skill and therefore reduce the uncertainty inherent in the climatic projections.

Keywords: bias correction, climatic projections, numerical models, representative concentration pathways

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Authors: Juliana A. Knocikova, Yann Bouret, Médéric Argentina, Laurent Counillon

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Cell volume, together with membrane potential and intracellular hydrogen ion concentration, is an essential biophysical parameter for normal cellular activity. Cell volumes can be altered by osmotically active compounds and extracellular tonicity. In this study, a simple mathematical model of osmotically induced cell swelling and shrinking is presented. Emphasis is given to water diffusion across the membrane. The mathematical description of the cellular behavior consists in a system of coupled ordinary differential equations. We compare experimental data of cell volume alterations driven by differences in osmotic pressure with mathematical simulations under hypotonic and hypertonic conditions. Implications for a future model are also discussed.

Keywords: eukaryotic cell, mathematical modeling, osmosis, volume alterations

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Authors: Yosra M. Badiei, Evelyn Ortiz, Marisa Portenti, David Szalda

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Water-oxidation half-reaction is a critical reaction that can be driven by a sustainable energy source (e.g., solar or wind) and be coupled with a chemical fuel making reaction which stores the released electrons and protons from water (e.g., H₂ or methanol). The use of molecular water-oxidation catalysts (WOC) allow the rationale design of redox active metal centers and provides a better understanding of their structure-activity-relationship. Herein, the structure of a Ru(III) complex bearing a doubly deprotonated N,N'-bis(aryl)pyridine-2,6-dicarboxamide ligand which contains a water molecule in its primary coordination sphere was elucidated by single-crystal X-ray diffraction. Further spectroscopic experimental data and pH-dependent electrochemical studies reveal its water-oxidation reactivity. Emphasis on mechanistic details for O₂ formation of this complex will be addressed.

Keywords: water-oxidation, catalysis, ruthenium, artificial photosynthesis

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Authors: Jalila Jbilou, Salaheddine El Adlouni, Pierre Gosselin

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Background: West Nile virus is increasingly an important public health issue in North America. In Canada, WVN was officially reported in Toronto and Montréal for the first time in 2001. During the last decade, several WNV events have been reported in several Canadian provinces. The main objective of the present study is to update the frequency of the climate conditions favorable to WNV outbreaks in Canada. Method: Statistical frequency analysis has been used to estimate the return period for climate conditions associated with WNV outbreaks for the 1961–2050 period. The best fit is selected through the Akaike Information Criterion, and the parameters are estimated using the maximum likelihood approach. Results: Results show that the climate conditions related to the 2002 event, for Montreal and Toronto, are becoming more frequent. For Saskatoon, the highest DD20 events recorded for the last few decades were observed in 2003 and 2007. The estimated return periods are 30 years and 70 years, respectively. Conclusion: The emergence of WNV was related to extremely high DD values in the summer. However, some exceptions may be related to several factors such as virus persistence, vector migration, and also improved diagnosis and reporting levels. It is clear that such climate conditions have become much more common in the last decade and will likely continue to do so over future decades.

Keywords: West Nile virus, climate, North America, statistical frequency analysis, risk estimation, public health, modeling, scenario, temperature, precipitation

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Authors: Gokhan Zengin, Abdurrahman Aktumsek

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The key enzyme inhibitory theory is one of the most accepted strategies in the treatment of global health problems including Alzheimer’s Disease and Diabetes mellitus. For this reason, the enzyme inhibitory potentials of different solvent extracts from Linaria genistifolia subsp. genistifolia were investigated against cholinesterase, and tyrosinase. The in vitro enzyme inhibitory potentials were measured with a microplate reader. The acetone and methanol extracts exhibited the strongest enzyme inhibitory effects on cholinesterase. However, the water extract was only active on tyrosinase. The results suggested that Linaria genistifolia subsp. genistifolia could be considered as a source of natural enzyme inhibitors for the treatment of major health problems.

Keywords: enzyme inhibitors, cholinesterase, tyrosinase, linaria, Turkey

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Authors: Mahdi Momeni

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The arrival of Mysticism to the subcontinent can be generally divided into two periods. The first period, was the Sporadic arrival of Sufis whom were traveling to the subcontinent according to the tradition of disquisition and the second period was; when the Sufi dynasties were sending missionaries and caliphs to guide and promote people from different direction to that land. Among the Sufi dynasty that entered to India in the thirteenth century, two dynasties of Chishti and Suhrawardîya were more successful than other Sufi dynasties. And thus they are very important in the spread of Islam and Mysticism to the subcontinent. Suhrawardiyya dynasty was founded by Sheikh Ziauddin Abu Najib Suhrawardi and was developed and spread by his nephew Sheikh Shahabuddin Suhrawardi Abo hafs Omar. Sheikh Shahabuddin sent many Caliphs and missionaries to India. Among these missionaries were People like Sultan Sakhi Sarwar, Seyyed Noureddin Mobarak Ghaznavi, Sheikh Jalal al-din Tabrizi and Sheikh Zakariya Multani. Since Suhrawardiyya doctrine relies on Asceticism and Sharia, so one of the important elements among Suhrawardiyya missionaries was inviting people to Islam. Accordingly Sheikh Shahab Caliphs had a great role in the spread of Islam and Mysticism in different territories, especially India. Such that it can be pointed out is the the role of Sheikh Baha-ud-din Zakariya Multani, the founder of Suhrawardiyya Dynasty in India. Sheikh Zakaria Multani after working in three areas, establishing monasteries, training managers, having numerous trips to different places, participating to social affairs provided the spread of Islam and Mysticism in subcontinent. This paper studies his role and actions in the subcontinent.

Keywords: islam, sufism, Suhrawardiyya, subcontinent, Multan

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Authors: S. Colclough, V. Costanzo, K. Fabbri, S. Piraccini, P. Griffiths

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The near Zero Energy Building (nZEB) standard is required for all buildings from 2020. The Passive House (PH) standard is a well-established low-energy building standard, having been designed over 25 years ago, and could potentially be used to achieve the nZEB standard in combination with renewables. By comparing measured performance with design predictions, this paper considers if there is a performance gap for a number of monitored properties and assesses if the nZEB standard can be achieved by following the well-established PH scheme. Analysis is carried out based on monitoring results from real buildings located in Northern Ireland, the Republic of Ireland and Italy respectively, with particular focus on the indoor air quality including the assumed and measured indoor temperature and heating periods for both standards as recorded during a full annual cycle. An analysis is carried out also on the energy performance certificates of each of the dwellings to determine if they meet the near Zero Energy Buildings primary energy consumption targets set in the respective jurisdictions. Each of the dwellings is certified as complying with the passive house standard, and accordingly have very good insulation levels, heat recovery and ventilation systems of greater than 75% efficiency and an airtightness of less than 0.6 air changes per hour at 50 Pa. It is found that indoor temperature and relative humidity were within the comfort boundaries set in the design stage, while carbon dioxide concentrations are sometimes higher than the values suggested by EN 15251 Standard for comfort class I especially in bedrooms.

Keywords: monitoring campaign, nZEB (near zero energy buildings), Passivhaus, performance gap

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Authors: Mohamed Gar Alalm, Shinichi Ookawara, Ahmed Tawfik

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In the present work, photocatalytic oxidation of phenol by iron (Fe+2) doped titanium dioxide (TiO2) was studied. The source of irradiation was solar simulated light under measured UV flux. The effect of light intensity, pH, catalyst loading, and initial concentration of phenol were investigated. The maximum removal of phenol at optimum conditions was 78%. The optimum pH was 5.3. The most effective degradation occurred when the catalyst dosage was 600 mg/L. increasing the initial concentration of phenol decreased the degradation efficiency due to the deactivation of active sites by additional intermediates. Phenol photocatalytic degradation moderately fitted to the pseudo-first order kinetic equation approximated from Langmuir–Hinshelwood model.

Keywords: phenol, photocatalytic, solar, titanium dioxide

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Authors: Adel A. Ghobbar, Ahmad Bakkar

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Although special care is given to maintenance, aircraft systems fail, and these failures cause delays and cancellations. The occurrence of Delays and Cancellations affects operators and manufacturers negatively. To reduce technical delays and cancellations, one should be able to determine the important systems causing them. The goal of this research is to find a method to define the most expensive delays and cancellations systems for Airline operators. A predictive model was introduced to forecast the failure and their impact after carrying out research that identifies relevant information to tackle the problems faced while answering the questions of this paper. Data were obtained from the manufacturers’ services reliability team database. Subsequently, delays and cancellations evaluation methods were identified. No cost estimation methods were used due to their complexity. The model was developed, and it takes into account the frequency of delays and cancellations and uses weighting factors to give an indication of the severity of their duration. The weighting factors are based on customer experience. The data Analysis approach has shown that delays and cancellations events are not seasonal and do not follow any specific trends. The use of weighting factor does have an influence on the shortlist over short periods (Monthly) but not the analyzed period of three years. Landing gear and the navigation system are among the top 3 factors causing delays and cancellations for all three aircraft types. The results did confirm that the cooperation between certain operators and manufacture reduce the impact of delays and cancellations.

Keywords: reliability, availability, delays & cancellations, aircraft maintenance

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Authors: T. Salami, O. S. Idowu, N. J. Bello

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Climatic variability is an essential issue when dealing with the issue of climate change. Variability of some climate parameter helps to determine how variable the climatic condition of a region will behave. The most important of these climatic variables which help to determine the climatic condition in an area are both the Temperature and Precipitation. This research deals with Longterm climatic variability in Nigeria. Variables examined in this analysis include near-surface temperature, near surface minimum temperature, maximum temperature, relative humidity, vapour pressure, precipitation, wet-day frequency and cloud cover using data ranging between 1901-2010. Analyses were carried out and the following methods were used: - Regression and EOF analysis. Results show that the annual average, minimum and maximum near-surface temperature all gradually increases from 1901 to 2010. And they are in the same case in a wet season and dry season. Minimum near-surface temperature, with its linear trends are significant for annual, wet season and dry season means. However, the diurnal temperature range decreases in the recent 100 years imply that the minimum near-surface temperature has increased more than the maximum. Both precipitation and wet day frequency decline from the analysis, demonstrating that Nigeria has become dryer than before by the way of rainfall. Temperature and precipitation variability has become very high during these periods especially in the Northern areas. Areas which had excessive rainfall were confronted with flooding and other related issues while area that had less precipitation were all confronted with drought. More practical issues will be presented.

Keywords: climate, variability, flooding, excessive rainfall

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Authors: Marielle Mansour

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Background: Integrating university students into an academic environment can be intense, with significant intellectual and emotional challenges. Stress, particularly during exam periods, plays a crucial role in students' eating habits, often influencing their food choices through mechanisms such as emotional eating. Objective: This study aims to understand the impact of exam stress on emotional eating among university students in Lebanon, Methodology: A cross-sectional study was conducted among 700 students aged 18 to 25 years in Lebanon, using online questionnaires to assess perceived stress using the Perceived Stress Scale (PSS) and emotional eating behaviors with the Dutch Eating Behavior Questionnaire (DEBQ). Data was analyzed to identify correlations between stress and emotional eating. Results: A significant positive correlation was observed between levels of perceived stress and increased emotional eating, with marked differences depending on participants' gender and field of study. This trend highlights the concerning impact of academic stress on students' food choices, including an increased prevalence of emotional eating among women and those studying in demanding disciplines like health sciences and engineering. Conclusion: This research contributes to the understanding of the complex links between academic stress and emotional eating behaviors among university students in Lebanon. To improve the mental and physical health of students, it is essential to implement tailored educational and support initiatives aimed at reducing stress and promoting balanced dietary choices in learning environments.

Keywords: exam stress, emotional eating, university students, stress management, Lebanon

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Authors: Abdulrazaq Yahaya, Omobola Okoh, Anthony Okoh

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Polychlorinated biphenyls (PCBs) are generated from short emission or leakage from capacitors and electrical transformers, industrial chemicals wastewater discharge and careless disposal of wastes. They are toxic, semi-volatile compounds which can persist in the environment, hence classified as persistent organic pollutants. Their presence in the environmental matrices has become a global concern. In this study, we assessed the concentrations and distribution patterns of 19 polychlorinated biphenyls congeners (PCB 1, 5, 18, 31, 44, 52, 66, 87, 101, 110, 138, 141, 151, 153, 170, 180, 183, 187, and 206) at six sampling points in water along the course of Buffalo River, Eastern Cape, South Africa. Solvent extraction followed by sulphuric acid, potassium permanganate and silica gel cleanup were used in this study. The analysis was done with gas chromatography electron capture detector (GC-ECD). The results of the analysis of all the 19 PCBs congeners ranged from not detectable to 0.52 ppb and 2.5 ppb during summer and autumn periods respectively. These values are generally higher than the World Health Organization (WHO) maximum permissible limit. Their presence in the waterbody suggests an increase in anthropogenic activities over the seasons. In view of their volatility, the compounds are transportable over long distances by air currents away from their point of origin putting the health of the communities at risk, thus suggesting the need for strict regulations on the use as well as save disposal of this group of compounds in the communities.

Keywords: organic pollutants, polychlorinated biphenyls, pollution, solvent extraction

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Authors: Hafiz Md. Hasan Babu, Khandaker Mohammad Mohi Uddin, Nitish Biswas, Sarreha Tasmin Rikta, Nuzmul Hossain Nahid

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Nanomedicine and bioengineering use biological systems that can perform computing operations. In a biocomputational circuit, different types of biomolecules and DNA (Deoxyribose Nucleic Acid) are used as active components. DNA computing has the capability of performing parallel processing and a large storage capacity that makes it diverse from other computing systems. In most processors, the multiplier is treated as a core hardware block, and multiplication is one of the time-consuming and lengthy tasks. In this paper, cost-effective DNA multipliers are designed using algorithms of molecular DNA operations with respect to conventional ones. The speed and storage capacity of a DNA multiplier are also much higher than a traditional silicon-based multiplier.

Keywords: biological systems, DNA multiplier, large storage, parallel processing

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Authors: Feran Asur

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In cities, plants; with its visual and functional effects, it helps to provide balance between human and environmental system. It is possible to develop alternative solutions to eliminate visual pollution by evaluating the potential properties of plant materials with other inanimate materials such as color, texture, form, size, etc. characteristics and other inanimate materials such as highlighter, background forming, harmonizing and concealer. In cold climates, the number of ornamental plant species that grow in warmer climates is less. For this reason, especially in the landscaping works of urban spaces, it is difficult to create the desired visuality with aesthetically qualified plants that are suitable for the ecology of the area, without creating monotony, with color variety. In this study, the importance of plant and plant compositions in the solution of visual problems in urban environments in cold climatic conditions is emphasized. The potential of ornamental plants that can be used for this purpose in preventing visual pollution is given. It has been shown how to use prominent features of these ornamental plants such as size, form, texture, vegetation periods to improve visual landscape in urban spaces in a long time. In addition to the design group disciplines that have activity on planning or application basis in the city and its surroundings, landscape architecture discipline can provide visual improvement of the studies to be carried out in detail in terms of planting design.

Keywords: residential landscape, planting, urban space, visual improvement

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Authors: Ahmed A. Al-Amiery, Yasmin K. Al-Majedy, Abdul Amir H. Kadhum, Abu Bakar Mohamad

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The efficiency of synthesized thiosemicarbazone namely 2-(1,5-dimethyl-4-(2-methylbenzylidene)amino)-2-phenyl-1H-pyrazol-3(2H)-ylidene) hydrazinecarbothioamide investigated as corrosion inhibitor of mild steel in 1N H2SO4 using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PD) in addition of scanning electron microscopy (SEM). The results showed that this inhibitor behaved as a good corrosion inhibitor even at low concentration with a mean efficiency of 93%. Polarization technique and EIS were tested in different concentrations reveal that this compound is adsorbed on the mild steel, therefore blocking the active sites and the adsorption follows the Langmuir adsorption isotherm model. SEM shows that mild steel surface is nearly perfect for mild steel which was immersed in a solution of H2SO4 with corrosion inhibitor.

Keywords: corrosion inhibitor, thiosemicarbazide, electrochemical impedance, electrochemical impedance spectroscopy

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Authors: Gagnesh Kumar, Nitin Gupta

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Ternary Content Addressable Memory cells are mainly popular in network routers for packet forwarding and packet classification, but they are also useful in a variety of other applications that require high-speed table look-up. The main TCAM-design challenge is to decrease the power consumption associated with the large amount of parallel active circuitry, without compromising with speed or memory density. Furthermore, when the channel length decreases, leakage power becomes more significant, and it can even dominate dynamic power at lower technologies. In this paper, we propose a TCAM-design technique, called Virtual Power Supply technique that reduces the leakage by a substantial amount.

Keywords: match line (ML), search line (SL), ternary content addressable memory (TCAM), Leakage power (LP)

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Authors: Jinsiang Shaw, Shih-Chieh Tseng

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Active vibration control is good for low frequency excitation, with advantages of light weight and adaptability. This paper use a macro-fiber composite (MFC) actuator for vibration suppression in a cantilevered beam due to its higher output force to suppress the disturbance. A fuzzy sliding mode controller is developed and applied to this system. Experimental results illustrate that the controller and MFC actuator are very effective in attenuating the structural vibration near the first resonant freuqency. Furthermore, this controller is shown to outperform the traditional skyhook controller, with nearly 90% of the vibration suppressed at the first resonant frequency of the structure.

Keywords: Fuzzy sliding mode controller, macro-fiber-composite actuator, skyhook controller, vibration suppression

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Authors: Ragini Trehan, D.K. Srivastava

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In the post-planning era, India’s fiscal transfers from the central to state governments are solely determined by the Finance Commissions (FCs). While in some of the well-established federations such as Australia, Canada, and Germany, equalization serves as the guiding principle of fiscal transfers and is constitutionally mandated, in India, it is not explicitly mandated, and FCs attempt to implement it indirectly by a combination of a formula-based share in the divisible pool of central taxes supplemented by a set of grants. In this context, it is important to measure the extent of equalization that is achieved through FC transfers with a view to improving the design of such transfers. This study uses an index-based methodology for measuring the degree of equalization achieved through FC-transfers covering the period from FC12 to the first year of FC15 spanning from 2005-06 to 2020-21. The ‘Index of Equalization’ shows that the extent of equalization has remained low in the range of 30% to 37% for the four Commission periods under review. The highest degree of equalization at 36.7% was witnessed in the FC12 period and the lowest equalization at 29.5% was achieved during the FC15(1) period. The equalizing efficiency of recommended transfers also shows a consistent fall from 11.4% in the FC12 period to 7.5% by the FC15 (1) period. Further, considering progressivity in fiscal transfers as a special case of equalizing transfers, this study shows that the scheme of per capita total transfers when determined using the equalization approach is more progressive and is characterized by minimal deviations as compared to the profile of transfers recommended by recent FCs.

Keywords: fiscal transfers, index of equalization, equalizing efficiency, fiscal capacity, expenditure needs, finance Commission, tax effort

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Authors: Ahmed Rouili

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Cantilever L-shaped walls are known to be relatively economical as retaining solution. The design starts by proportioning the wall dimensions for which the stability is checked for. A ratio between the lengths of the base and the stem, falling between 0,5 to 0,7, ensure the stability requirements in most cases. However, the displacement pattern of the wall in terms of rotations and translations, and the lateral pressure profile, do not have the same figure for all wall’s proportioning, as it is usually assumed. In the present work, the results of a numerical analysis are presented, different wall geometries were considered. The results show that the proportioning governs the equilibrium between the instantaneous rotation and the translation of the wall-toe, also, the lateral pressure estimation based on the average value between the at-rest and the active pressure, recommended by most design standards, is found to be not applicable for all walls.

Keywords: cantilever wall, proportioning, numerical analysis, lateral pressure estimation

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Authors: Dereje Habte, Jane Namasasu

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Background: The aim of the analysis was to assess the practice of family planning (FP) among HIV-infected women and the influence of women’s awareness of HIV-positive status in the practice of FP. Methods: The analysis was made among 489 non-pregnant, sexually active, fecund women living with HIV. Result: Of the 489 confirmed HIV positive women, 184 (37.6%) reported that they knew they are HIV positive. The number of women with current use and unmet need of any family planning method were found to be 251 (51.2%) and 107 (21.9%) respectively. Women’s knowledge of HIV-positive status (AOR: 2.32(1.54,3.50)), secondary and above education (AOR: 2.36(1.16,4.78)), presence of 3-4 (AOR: 2.60(1.08,6.28)) and more than four alive children (AOR: 3.03(1.18,7.82)) were significantly associated with current use of family planning. Conclusion: Women’s awareness of HIV-positive status was found to significantly predict family planning practice among women living with HIV.

Keywords: family planning, HIV, Malawi, women

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Authors: Melissa Hachem, Lynda Bensefa-Colas, Isabelle Momas

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We evaluated the impact of the first lockdown restriction measures (March-May 2020) in the Paris area on (1) the variation of in-vehicle ultrafine particle (UFP) and black carbon (BC) concentrations between pre-and post-lockdown period and (2) the professional drivers working conditions and practices. The study was conducted on 33 Parisian taxi drivers. UFP and BC were measured inside their vehicles with DiSCmini® and microAeth®, respectively, on two typical working days before and after the first lockdown. The job-related characteristics were self-reported. Our results showed that after the first lockdown, the number of clients significantly decreased as well as the taxi driver's journey duration. Taxi drivers significantly opened their windows more and reduced the use of air recirculation. UFP decreased significantly by 32% and BC by 31% after the first lockdown, with a weaker positive correlation compared to before the lockdown. The reduction of in-vehicle UFP was explained mainly by the reduction of traffic flow and ventilation settings, though the latter probably varied according to the traffic condition. No predictor explained the variation of in-vehicle BC concentration between pre-and post-lockdown periods, suggesting different sources of UFP and BC. The road traffic was not anymore the dominant source of BC post-lockdown. We emphasize the role of traffic emissions on in-vehicle air pollution and that preventive measures such as ventilation settings will help to better manage air quality inside a vehicle in order to minimize exposure of professional drivers, as well as passengers, to air pollutants.

Keywords: black carbon, COVID-19, France, lockdown, taxis, ultrafine particles

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Authors: A. Brinda Lakshmi, J. Lakshmi Priya

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Cantaloupes (muskmelon and watermelon) contain biologically active molecules such as carotenoids which are natural pigments used as food colorants and afford health benefits. ß-carotene is the major source of carotenoids present in muskmelon and watermelon shell. Carotenoids were extracted using Microwave assisted extraction (MAE) and Ultrasound assisted extraction (UAE) utilising organic lipophilic solvents such as acetone, methanol, and hexane. Extraction conditions feed-solvent ratio, microwave power, ultrasound frequency, temperature and particle size were varied and optimized. It was found that the yield of carotenoids was higher using UAE than MAE, and muskmelon had the highest yield of carotenoids when was ethanol used as a solvent for 0.5 mm particle size.

Keywords: carotenoids, extraction, muskmelon shell, watermelon shell

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Authors: Ahmed Abbou, Ali Mousmi, Rachid El Akhrif

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This research paper aims to reduce the chattering phenomenon due to control by sliding mode control applied on a wind energy conversion system based on the doubly fed induction generator (DFIG). Our goal is to offset the effect of parametric uncertainties and come as close as possible to the dynamic response solicited by the control law in the ideal case and therefore force the active and reactive power generated by the DFIG to accurately follow the reference values which are provided to it. The simulation results using Matlab / Simulink demonstrate the efficiency and performance of the proposed technique while maintaining the simplicity of control by first order sliding mode.

Keywords: correction of the equivalent command, DFIG, induction machine, sliding mode controller

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Authors: Shynn Lim, Ching Tan

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The paper presents the PASSION Programme designed by a government school in Singapore, guided by national goals as well as research-based pedagogies that aims to nurture students to become lifelong learners with the strength of character. The design and enactment of the integrated approach to develop in students good character, resilience and social-emotional well-being, future readiness, and active citizenship is guided by a set of principles that amalgamates Biesta’s domains of purposes of education and authentic learning. Data in terms of evidence of students’ learning and students’ feedback were collected, analysed, and suggests that the learning experience benefitted students by boosting their self-confidence, self-directed and collaborative learning skills, as well as empathy.

Keywords: lifelong learning, character and citizenship education, education and career guidance, 21CC, teaching and learning empathy

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Authors: Ali Ben Abbes, ImedRiadh Farah, Vincent Barra

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Remotely sensed data are a significant source for monitoring and updating databases for land use/cover. Nowadays, changes detection of urban area has been a subject of intensive researches. Timely and accurate data on spatio-temporal changes of urban areas are therefore required. The data extracted from multi-temporal satellite images are usually non-stationary. In fact, the changes evolve in time and space. This paper is an attempt to propose a methodology for changes detection in urban area by combining a non-stationary decomposition method and stochastic modeling. We consider as input of our methodology a sequence of satellite images I₁, I₂, … I_n at different periods (t = 1, 2, ..., n). Firstly, a preprocessing of multi-temporal satellite images is applied. (e.g. radiometric, atmospheric and geometric). The systematic study of global urban expansion in our methodology can be approached in two ways: The first considers the urban area as one same object as opposed to non-urban areas (e.g. vegetation, bare soil and water). The objective is to extract the urban mask. The second one aims to obtain a more knowledge of urban area, distinguishing different types of tissue within the urban area. In order to validate our approach, we used a database of Tres Cantos-Madrid in Spain, which is derived from Landsat for a period (from January 2004 to July 2013) by collecting two frames per year at a spatial resolution of 25 meters. The obtained results show the effectiveness of our method.

Keywords: multi-temporal satellite image, urban growth, non-stationary, stochastic model

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Authors: Maryam Ghoreishi, Christian Larsen

Abstract:

In this paper, we investigate the effect of stochastic inputs on problem of joint optimal pricing and lot-sizing decisions where the inventory cycle is divided into advance and spot sales periods. During the advance sales period, customer can make reservations while customer with reservations can cancel their order. However, during the spot sales period customers receive the order as soon as the order is placed, but they cannot make any reservation or cancellation during that period. We assume that the inter arrival times during the advance sales and spot sales period are exponentially distributed where the arrival rate is decreasing function of price. Moreover, we assume that the number of cancelled reservations is binomially distributed. In addition, we assume that deterioration process follows an exponential distribution. We investigate two cases. First, we consider two-state case where we find the optimal price during the spot sales period and the optimal price during the advance sales period. Next, we develop a generalized case where we extend two-state case also to allow dynamic prices during the spot sales period. We apply the Markov decision theory in order to find the optimal solutions. In addition, for the generalized case, we apply the policy iteration algorithm in order to find the optimal prices, the optimal lot-size and maximum advance sales amount.

Keywords: inventory control, pricing, Markov decision theory, advance sales system

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Authors: Noureddine Ben Ayed, Abdelkader Soumaya, Saïd Maouche, Ali Kadri, Mongi Gueddiche, Hayet Khayati-Ammar, Ahmed Braham

Abstract:

The archaeological monument of Utica, located in north-eastern Tunisia, was founded (8th century BC) By the Phoenicians as a port installed on the trade route connecting Phoenicia and the Straits of Gibraltar in the Mediterranean Sea. The flourishment of this city as an important settlement during the Roman period was followed by a sudden abandonment, disuse and progressive oblivion in the first half of the fifth century AD. This decadence can be attributed to the destructive earthquake of 5 July 408 - 410 AD, affecting this historic city as documented in 1906 by the seismologist Fernand De Montessus De Ballore. The magnitude of the Utica earthquake was estimated at 6.8 by the Tunisian National Institute of Meteorology (INM). In order to highlight the damage caused by this earthquake, a field survey was carried out at the Utica ruins to detect and analyse the earthquake archaeological effects (EAEs) using structural geology methods. This approach allowed us to highlight several structural damages, including: (1) folded mortar pavements, (2) cracks affecting the mosaic and walls of a water basin in the "House of the Grand Oecus", (3) displaced columns, (4) block extrusion in masonry walls, (5) undulations in mosaic pavements, (6) tilted walls. The structural analysis of these EAEs and data measurements reveal a seismic cause for all evidence of deformation in the Utica monument. The maximum horizontal strain of the ground (e.g. SHmax) inferred from the building oriented damage in Utica shows a NNW-SSE direction under a compressive tectonic regime. For the seismogenic source of this earthquake, we propose the active E-W to NE-SW trending Utique - Ghar El Melh reverse fault, passing through the Utica Monument and extending towards the Ghar El Melh Lake, as the causative tectonic structure. The active fault trace is well supported by instrumental seismicity, geophysical data (e.g., gravity, seismic profiles) and geomorphological analyses. In summary, we find that the archaeoseismic records detected at Utica are similar to those observed at many other archaeological sites affected by destructive ancient earthquakes around the world. Furthermore, the calculated orientation of the average maximum horizontal stress (SHmax) closely match the state of the actual stress field, as highlighted by some earthquake focal mechanisms in this region.

Keywords: Tunisia, utica, seimogenic fault, archaeological earthquake effects

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