Search results for: design point

Authors: Felsy J. Sandi

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There is a potential of growth in the spa industry due to the influx of domestic and international tourist coming to Sabah, Malaysia. It is a good opportunity to venture into this industry for the country’s economic future growth, and therefore, it is essential for this area to be researched. Being one of the fastest growing industries in the world, has led to enormous challenges, which need to be addressed. Malaysia is also riding with this phenomenon. The President of the Malaysian Association of Wellness and Spa stated that the misconception about the Spa industry’s image, especially amongst the elderly is the biggest challenge faced by the industry, as they perceived the spa industry is equivalent to a prostitution center. Therefore, the objective of this study is to explore the issue by analyzing whether image can be added in the theory of planned behavior to better understand the consumer’s intention to visit, in the spa context. The Theory of Planned Behavior by Ajzen, a theory or model in predicting intention, has three constructs; such as Attitude as the first construct, the second construct is Subjective Norm and the third construct is Perceived Behavioral Control. Qualitative research is used as this is an exploratory research. The site of study will be at Jari Jari Spa, located in Kota Kinabalu, the only spa in Sabah that was awarded as the Center of Excellence (CoE) by the Ministry of Tourism and Culture in Malaysia. The findings propose to provide useful information to the relevant stakeholders on ways to approach local customers to convince them to visit the spa and for spa marketers to help them develop and design effective marketing strategies. Future investigation should consider more on the perception and loyalty of the local customers.

Keywords: consumer's perception, image, local customer, spa, visit intention

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Authors: Teresa Azevedo PerdicoúLis, Paulo Lopes Dos Santos

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The conceptualisation of the problem of network optimisation as a noncooperative game sets up a holistic interactive approach that brings together different network features (e.g., com-pressor stations, sources, and pipelines, in the gas context) where the optimisation objectives are different, and a single optimisation procedure becomes possible without having to feed results from diverse software packages into each other. A mathematical model of this type, where independent entities take action, offers the ideal modularity and subsequent problem decomposition in view to design a decentralised algorithm to optimise the operation and management of the network. In a game framework, compressor stations and sources are under-stood as players which communicate through network connectivity constraints–the pipeline model. That is, in a scheme similar to tatonnementˆ, the players appoint their best settings and then interact to check for network feasibility. The devolved degree of network unfeasibility informs the players about the ’quality’ of their settings, and this two-phase iterative scheme is repeated until a global optimum is obtained. Due to network transients, its optimisation needs to be assessed at different points of the control interval. For this reason, the proposed approach to optimisation has two stages: (i) the first stage computes along the period of optimisation in order to fulfil the requirement just mentioned; (ii) the second stage is initialised with the solution found by the problem computed at the first stage, and computes in the end of the period of optimisation to rectify the solution found at the first stage. The liability of the proposed scheme is proven correct on an abstract prototype and three example networks.

Keywords: connectivity matrix, gas network optimisation, large-scale, noncooperative game, system decomposition

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Authors: Margareta Simina Stanc, Aurel Mototolea, Tiberiu Potarniche

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Sacidava archeological site is located in Dobrudja region, Romania, on a hill on the right bank of the Danube - the Musait point, located at about 5 km north-east from Dunareni village. The place-name documents the fact that, prior to the Roman conquest, in the area, there was a Getic settlement. The location of the Sacidava was made possible by corroborating the data provided by the ancient sources with the epigraphic documents (the milial pillar during the time of Emperor Decius). The tegular findings attest that an infantry unit, cohors I Cilicum milliaria equitata, as well as detachments from Legio V Macedonica and Legio XI Claudia, were confined to Sacidava. During the period of the Dominion, the garrison of the fortification is the host of a cavalry unit: cuneus equitum scutariorum. In the immediate vicinity to the Roman fortress, to the east, were identified two other fortifications: a Getic settlement (4th-1st century B.C.) and an Early Medieval settlement (9th-10th century A.C.). The archaeological material recovered during the research is represented by ceramic forms such as amphoras, jugs, pots, cups, plates, to which are added oil lamps, some of them typologically new at the time of discovery. Local ceramic shapes were also founded, worked by hand or by wheel, considered un-Romanized or in the course of Romanization. During the time of the Principality, Sacidava it represented an important military outpost serving mainly the city of Tropaeum Traiani, controlling also the supply and transport on the Danube limes in the Moesic sector. This role will determine the development of the fortress and the appearance of extramuros civil structures, thus becoming an important landmark during the 5th-6th centuries A.C., becoming a representation of power of the Roman empire in an area of continuous conflict. During recent archaeological researches, faunal remains were recovered, and their analysis allowed to estimate the animal resources and subsistence practices (animal husbandry, hunting, fishing) in the settlement. The methodology was specific to archaeozoology, mainly consisting of anatomical, taxonomical, and taphonomical identifications, recording, and quantification of the data. The remains of domestic mammals have the highest proportion indicating the importance of animal husbandry; the predominant species are Bos taurus, Ovis aries/Capra hircus, and Sus domesticus. Fishing and hunting were of secondary importance in the subsistence economy of the community. Wild boar and the red deer were the most frequently hunted species. Just a few fish bones were recovered. Thus, the ancient city of Sacidava is proving to be an important element of cultural heritage of the south-eastern part of Romania, for whose conservation and enhancement efforts must be made, especially by landscape reconstruction.

Keywords: archaeozoology, landscape reconstruction, limes, military outpost

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Authors: B. Ozarisoy, E. Ampatzi, G. Z. Lancaster

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This research project is undertaken in the Turkish Republic of Northern Cyprus (T.R.N.C). The study focuses on identifying refurbishment activities capable of diagnosing and detecting the underlying problems alongside the challenges offered by the buildings’ typology in addition to identifying the correct construction materials in the refurbishment process which allow for the maximisation of expected energy savings. Attention is drawn to, the level of awareness and understanding of refurbishment activity that needs to be raised in the current construction process alongside factors that include the positive environmental impact and the saving of energy. The approach here is to look at buildings that have been built by private construction companies that have already been refurbished by occupants and to suggest additional control mechanisms for retrofitting that can further enhance the process of renewal. The objective of the research is to investigate the occupants’ behaviour and role in the refurbishment activity; to explore how and why occupants decide to change building components and to understand why and how occupants consider using energy-efficient materials. The present work is based on data from this researcher’s first-hand experience and incorporates the preliminary data collection on recent housing sector statistics, including the year in which housing estates were built, an examination of the characteristics that define the construction industry in the T.R.N.C., building typology and the demographic structure of house owners. The housing estates are chosen from 16 different projects in four different regions of the T.R.N.C. that include urban and suburban areas. There is, therefore, a broad representation of the common drivers in the property market, each with different levels of refurbishment activity and this is coupled with different samplings from different climatic regions within the T.R.N.C. The study is conducted through semi-structured interviews to identify occupants’ behaviour as it is associated with refurbishment activity. The interviews provide all the occupants’ demographic information, needs and intentions as they relate to various aspects of the refurbishment process. This research paper presents the results of semi-structured interviews with 70 homeowners in a selected group of 16 housing estates in five different parts of the T.R.N.C. The people who agreed to be interviewed in this study are all residents of single or multi-family housing units. Alongside the construction process and its impact on the environment, the results point out the need for control mechanisms in the housing sector to promote and support the adoption of retrofit strategies and minimize non-controlled refurbishment activities, in line with diagnostic information of the selected buildings. The expected solutions should be effective, environmentally acceptable and feasible given the type of housing projects under review, with due regard for their location, the climatic conditions within which they were undertaken, the socio-economic standing of the house owners and their attitudes, local resources and legislative constraints. Furthermore, the study goes on to insist on the practical and long-term economic benefits of refurbishment under the proper conditions and why this should be fully understood by the householders.

Keywords: construction process, energy-efficiency, refurbishment activity, retrofitting

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Authors: Lela Pintarić, Iva Rezić, Ana Vrsalović Presečki

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Considering an enormous increase of the use of metal nanoparticles with the exactly defined characteristics, the main goal of this research was to found the optimal and environmental friendly method of their synthesis. The synthesis of the inorganic core-shell nanoparticles was optimized as a model. The core-shell nanoparticles are composed of the enzyme core belted with the metal ions, oxides or salts as a shell. In this research, enzyme urease was the core catalyst and the shell nanoparticle was made of silver. Silver nanoparticles are widespread utilized and some of their common uses are: as an addition to disinfectants to ensure an aseptic environment for the patients, as a surface coating for neurosurgical shunts and venous catheters, as an addition to implants, in production of socks for diabetics and athletic clothing where they improve antibacterial characteristics, etc. Characteristics of synthesized nanoparticles directly depend on of their size, so the special care during this optimization was given to the determination of the size of the synthesized nanoparticles. For the purpose of the above mentioned optimization, sixteen experiments were generated by the Design of Experiments (DoE) method and conducted under various temperatures, with different initial concentration of the silver nitrate and constant concentration of the urease of two separate manufacturers. Synthesized nanoparticles were analyzed by the Nanoparticle Tracking Analysis (NTA) method on Malvern NanoSight NS300. Results showed that the initial concentration of the silver ions does not affect the concentration of the synthesized silver nanoparticles neither their size distribution. On the other hand, temperature of the experiments has affected both of the mentioned values.

Keywords: core-shell nanoparticles, optimization, silver, urease

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Authors: Roseline Chizoba Onuoha, Rose Ngozi Uzoka

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This study aimed at investigating perceived effect of physical exercise on healthy well-being of pregnant mothers in Imo state. The study was guided by three research questions and three null hypotheses tested at 0.05 level of significance. The study was a quasi-experimental non-equivalent control group design involving pre and post tests. A sample of 92 pregnant women drawn from a total population of 922 registered pregnant women in ten randomly selected health centers in Imo State through multistage sampling technique was used. A 41 item structured instrument titled Physical Exercise Pregnancy Test (PEPT) was used for the study. The PEPT was validated by three experts from measurement and evaluation, educational psychology and health education. Crombach Alpha method was used to determine the reliability of Physical Exercise Pregnancy Test (PEPT) and reliability index of 0.82 was obtained. Mean and standard deviation were used to answer the research questions; while Analysis of Covariance (ANCOVA) was used in analyzing the hypotheses. Findings of the study revealed that physical exercise affects physical, social and emotional wellbeing scores of pregnant women. The study also indicated that intervention using physical exercise significantly enhanced healthy well-being scores of pregnant mothers who were exposed to physical exercise than those who received conventional health talks; Location has no significant interaction effect on the mean well-being scores of pregnant women via PEPT. Among recommendations made were that pregnant women should participate in physical exercise.

Keywords: educational psychology, Imo state, Physical exercise, pregnant women

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Authors: Mahadzirah Mohamad, Morliyati Mohammad, Nor Azman Mat Ali, Zainudin Awang

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Globally, youth substance abuse has been identified as the problem that causes substantial damage not only to individuals, but also to families and communities. In addition, substance abuse youths have become unproductive resources that would play lesser roles in the nation’s development. The increasing trend of substance abuse among youths has raised a lot of concern among various quarters in Malaysia. It has also been reported that Malay youths are the majority group involved in substance abuse. However, it was noted that life satisfaction had been found to be an important mitigating factor that addressed substance abuse. The objectives of the study were twofold: firstly, to ascertain the effect of life satisfaction on substance abuse among Malay youth. Secondly, to identify the role of delinquency on the relationship between life satisfaction and substance abuse. This study adopted a cross-sectional research design. Self-administered questionnaires were distributed to 500 Malay youths at the youth programmes using a two-step sampling technique: area sampling and systematic sampling. The research hypotheses were tested using Structural Equation Modelling. The findings of the study revealed that there is no significance relationship between life satisfaction and substance abuse. There is a significant inverse relationship between life satisfaction and delinquency. Moreover, delinquency has a positive significant influence on substance abuse. The use of Bootstrapping analysis proved that delinquency plays a full mediating role in the relationship between life satisfaction and substance abuse. This study suggested that life satisfaction has no effect on youth substance abuse. In order to reduce substance abuse, efforts should be undertaken to reduce delinquency behaviour by increasing youth life satisfaction.

Keywords: delinquency, life satisfaction, substance abuse, youth

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Authors: Szerena Vajkovszki

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Among the relatively large volume of literature, the role and perception of women in Buddhism have been examined from various perspectives such as theology, history, anthropology, and feminism. When Buddhism spread to the West, women had a major role in its adaption and development. The meeting of different cultures and social structures had the fruit of a necessity to change. As Buddhism gained attention in the West, it produced a Buddhist feminist identity across national and ethnic boundaries. So globalization produced a contemporary cross-cultural Buddhist Women. The aim of the research is to find out the new role of such a Buddhist woman in aging societies. More precisely to understand what effect this contemporary Buddhist religion may have, direct or indirect, on fertility. Our worldwide aging society, especially in developed countries, including members of EU, raise sophisticated sociological and economic issues and challenges to be met. As declining fertility has outstanding influence underlying this trend, numerous studies have attempted to identify, describe, measure and interpret contributing factors of the fertility rate, out of which relatively few revealed the impact of religion. Among many religious guidelines, we can separate two major categories: direct and indirect. The aim of this research was to understand what are the most crucial identified (family values, gender related behaviors, religious sentiments) and not yet identified most influential contributing contemporary Buddhist religious factors. Above identifying these direct or indirect factors, it is also important to understand to what extent and how do they influence fertility, which requires a wider (inter-discipline) perspective. As proved by previous studies religion has also an influential role in health, mental state, well-being, working activity and many other components that are also related to fertility rates. All these components are inter-related, hence direct and indirect religious effects can only be well understood, if we figure out all necessary fields and their interaction. With the help of semi-structured opened interviews taking place in different countries, it was showed that indeed Buddhism has significant direct and indirect effect on fertility, hence the initial hypothesis was proved. However, the interviews showed an overall positive effect, the results could only serve for a general understanding about how Buddhism affects fertility. Evolution of Buddhism’s direct and indirect influence may vary in different nations and circumstances according to their specific environmental attributes. According to the local patterns, with special regard to women’s position and role in the society, outstandingly indirect influences could show diversifications. So it is advisory to investigate more for a deeper and clearer understanding of how Buddhism function in different socioeconomic circumstances. For example, in Hungary after the period of secularization more and more people tended to be attracted toward some transcendent values which could be an explanation for the rising number of Buddhists in the country. The present research could serve as a general starting point or a common basis for further specific national investigations how contemporary Buddhism affects fertility.

Keywords: contemporary Buddhism, cross-cultural woman, fertility, gender roles, religion

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Authors: T. Noichl, M. Cramer, G. E. Dlugosch, I. Hosenfeld

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Teachers are exposed to a variety of stresses in their work context. These can have a negative impact on physical and psychological well-being. The online training ‘Better Living! Self-care for teachers’ is based on the training ‘Better Living! Self-care for mental health professionals’, which has been proven to be effective over a period of 3 years. The training for teachers is being evaluated for its effectiveness between October 2021 and March 2023 in a study funded by the German Federal Ministry of Education and Research. The aim of the training is to promote self-care and mindfulness among participants and thereby to foster well-being. The concept of self-care was already mentioned in antiquity and was also named as an imperative by philosophers such as Socrates and Epictetus. In the absence of a universal understanding of self-care today, the following definition was developed within the research group: Self-care is 1) facing oneself in a loving and appreciative way, 2) taking one's own needs seriously, and 3) actively contributing to one's own well-being. The study is designed as a randomized wait-control group repeated-measures design with 4 (treatment group) resp. 6 (wait-control group) measurement points. Central dependent variables are self-care, mindfulness, stress, and well-being. To assess the long-term effectiveness of training participation, these constructs are surveyed at the beginning and the end of the training as well as five weeks and one year later. Based on the results of the evaluation with mental health professionals, it is expected that participation will lead to an increase in subjective well-being, self-care, and mindfulness. The first results of the evaluation study are presented and discussed with regard to the effectiveness of the training among teachers.

Keywords: longitudinal intervention study, mindfulness, self-care, teachers’ mental health, well-being

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Authors: Madeleine Nicole G. Bernardo, Katrina T. Feliciano, Marcelo Nonato A. Nacionales III, Diane Frances M. Peralta, Denise Nicole V. Profeta

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This study aims to find out if heart rate variability and valence of emotion have an effect on perceived intensity of emotion. Psychology undergraduates (N = 60) from the University of the Philippines Diliman were shown 10 photographs from the Japanese Female Facial Expression (JAFFE) Database, along with a corresponding questionnaire with a Likert scale on perceived intensity of emotion. In this 3 x 2 mixed subjects factorial design, each group was either made to do a simple exercise prior to answering the questionnaire in order to increase the heart rate, listen to a heart rate of 120 bpm, or colour a drawing to keep the heart rate stable. After doing the activity, the participants then answered the questionnaire, providing a rating of the faces according to the participants’ perceived emotional intensity on the photographs. The photographs presented were either of positive or negative emotional valence. The results of the experiment showed that neither an induced fast heart rate or perceived fast heart rate had any significant effect on the participants’ perceived intensity of emotion. There was also no interaction effect of heart rate variability and valence of emotion. The insignificance of results was explained by the Philippines’ high context culture, accompanied by the prevalence of both intensely valenced positive and negative emotions in Philippine society. Insignificance in the effects were also attributed to the Cannon-Bard theory, Schachter-Singer theory and various methodological limitations.

Keywords: heart rate variability, perceived intensity of emotion, Philippines , valence of emotion

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Authors: Hanan H. ALQahtani, Karen Jones

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Catching a ball during sitting is a functional exercise commonly used in rehabilitation to enhance trunk muscle activity. To progress this exercise, physiotherapists incorporate a Swiss ball or change seat height. However, no study has assessed the effect of different seating surfaces on trunk muscle activity while catching a ball. Objective: To investigate the effect of catching a ball during sitting on a Swiss ball, a low seat and a high seat on trunk muscle activity. Method: A repeated-measures, counterbalanced design was used. A total of 26 healthy participants (15 female and 11 male) performed three repetitions of catching a ball on each seating surface. Using surface electromyography (sEMG), the activity of the bilateral transversus abdominis/internal oblique (TrA/IO), rectus abdominis (RA), erector spinae (ES) and lumbar multifidus (MF) was recorded. Trunk muscle activity was normalized using maximum voluntary isometric contraction and analyzed. Statistical significance was set at p ≤ .05. Results: No significant differences were observed in the activity of RA, TrA/IO, ES or MF between a low seat and a Swiss ball. However, the activity of the right and left ES on a low seat was significantly greater than on a high seat (p = .017 and p = .017, respectively). Conversely, the activity of the right and left RA on a high seat was significantly greater than on a low seat (p = .007 and p = .004, respectively). Conclusion: This study suggests that replacing a low seat with a Swiss ball while catching a ball is insufficient to increase trunk muscle activity, whereas changing the seat height could induce different trunk muscle activities. However, research conducted on patients is needed before translating these results into clinical settings.

Keywords: catching, electromyography, seating, trunk

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Authors: B. K. Kanungo, Monika Thakur, Minati Baral

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8-hydroxyquinoline, (8HQ), experiences a renaissance due to its utility as a building block in metallosupramolecular chemistry and its versatile use of its derivatives in various fields of analytical chemistry, materials science, and pharmaceutics. It forms stable complexes with a variety of metal ions. Assembly of more than one such unit to form a polydentate chelator enhances its coordinating ability and the related properties due to the chelate effect resulting in high stability constant. Keeping in view the above, a nonadentate chelator N-[3,5-bis(8-hydroxyquinoline-2-amido)cyclohexyl]-8-hydroxyquinoline-2-carboxamide, (TACH2OX), containing a central cis,cis-1,3,5-triaminocyclohexane appended to three 8-hydroxyquinoline at 2-position through amide linkage is developed, and its solution thermodynamics, photophysical and Density Functional Theory (DFT) studies were undertaken. The synthesis of TACH2OX was carried out by condensation of cis,cis-1,3,5-triaminocyclohexane, (TACH) with 8‐hydroxyquinoline‐2‐carboxylic acid. The brown colored solid has been fully characterized through melting point, infrared, nuclear magnetic resonance, electrospray ionization mass and electronic spectroscopy. In solution, TACH2OX forms protonated complexes below pH 3.4, which consecutively deprotonates to generate trinegative ion with the rise of pH. Nine protonation constants for the ligand were obtained that ranges between 2.26 to 7.28. The interaction of the chelator with two trivalent metal ion Fe3+ and Al3+ were studied in aqueous solution at 298 K. The metal-ligand formation constants (ML) obtained by potentiometric and spectrophotometric method agree with each other. The protonated and hydrolyzed species were also detected in the system. The in-silico studies of the ligand, as well as the complexes including their protonated and deprotonated species assessed by density functional theory technique, gave an accurate correlation with each observed properties such as the protonation constants, stability constants, infra-red, nmr, electronic absorption and emission spectral bands. The nature of electronic and emission spectral bands in terms of number and type were ascertained from time-dependent density functional theory study and the natural transition orbitals (NTO). The global reactivity indices parameters were used for comparison of the reactivity of the ligand and the complex molecules. The natural bonding orbital (NBO) analysis could successfully describe the structure and bonding of the metal-ligand complexes specifying the percentage of contribution in atomic orbitals in the creation of molecular orbitals. The obtained high value of metal-ligand formation constants indicates that the newly synthesized chelator is a very powerful synthetic chelator. The minimum energy molecular modeling structure of the ligand suggests that the ligand, TACH2OX, in a tripodal fashion firmly coordinates to the metal ion as hexa-coordinated chelate displaying distorted octahedral geometry by binding through three sets of N, O- donor atoms, present in each pendant arm of the central tris-cyclohexaneamine tripod.

Keywords: complexes, DFT, formation constant, TACH2OX

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Authors: Rachell Denise S. Concepcion, Chantelle Vianca D. L. Cobarrubias, Kimberly B. Coloma, Celina Renee R. Colorado, Charlene S. Constantino, Huette Iris C. Consulta

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AIMS: This study determined the effect of motivational video in increasing the level of self-motivation among first year nursing students to pursue their nursing career. METHODS: A quantitative quasi experimental one-group pretest-posttest research design was used and purposive sampling technique was utilized. Motivation for Choosing Nursing as a Career Questionnaire was used in determining the level of motivation before and after using the motivational video. The of motivational video entitled, “Testimonials from Nurses” was used as the intervention wherein testimonials from successful Thomasian nursing graduates was considered and viewed by the students in order to inspire them to take nursing as their career. The subjects are nursing students who obtained a score ranging from 21-40 in the questionnaire. Before the viewing, the researchers provided a brief introduction and background to enable the participants to fully understand the contents. After which, debriefing was done. The data gathered was analyzed using the Paired T-Test using SPSS version 21.0. The Pre-test and Post-test scores were compared, which further statistically, differentiated by mean, standard deviation and t-test scores. Results: The t-test value is -17.221 and p value of 0.00 < 0.05 which indicates that there is a statistically significant change in the level of self-motivation of first year nursing students before and after viewing the motivational video. Conclusion: It was therefore concluded that motivational video entitled, “Testimonials From Nurses is an effective intervention in increasing the level of self-motivation of first year nursing students to pursue their nursing career.

Keywords: motivational video, freshmen, self-motivation, nursing career

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Authors: Gideon Nyuimbe Gasu

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Sub Saharan Africa is at a critical point, experiencing rapid population growth, particularly in urban areas and young growing force. At the same time, the growing risk of catastrophic global climate change threatens to weaken food production system, increase intensity and frequency of drought, flood, and fires and undermine gains on development and poverty reduction. Although the region has the lowest per capital greenhouse gas emission level in the world, it will need to join global efforts to address climate change, including action to avoid significant increases and to encourage a green economy. Thus, there is a need for the concept of 'greening the economy' as was prescribed at Rio Summit of 1992. Renewable energy is one of the criterions to achieve this laudable goal of maintaining a green economy. There is need to address climate change while facilitating continued economic growth and social progress as energy today is critical to economic growth. Fossil fuels remain the major contributor of greenhouse gas emission. Thus, cleaner technologies such as carbon capture storage, renewable energy have emerged to be commercially competitive. This paper sets out to examine how to achieve a low carbon economy with minimal emission of carbon dioxide and other greenhouse gases which is one of the outcomes of implementing a green economy. Also, the paper examines the different renewable energy sources such as nuclear, wind, hydro, biofuel, and solar voltaic as a panacea to the looming climate change menace. Finally, the paper assesses the different renewable energy and energy efficiency as a propeller to generating new sources of income and jobs and in turn reduces carbon emission. The research shall engage qualitative, evaluative and comparative methods. The research will employ both primary and secondary sources of information. The primary sources of information shall be drawn from the sub Saharan African region and the global environmental organizations, energy legislation, policies and related industries and the judicial processes. The secondary sources will be made up of some books, journal articles, commentaries, discussions, observations, explanations, expositions, suggestions, prescriptions and other material sourced from the internet on renewable energy as a panacea to climate change. All information obtained from these sources will be subject to content analysis. The research result will show that the entire planet is warming as a result of the activities of mankind which is clear evidence that the current development is fundamentally unsustainable. Equally, the study will reveal that a low carbon development pathway in the sub Saharan African region should be embraced to minimize emission of greenhouse gases such as using renewable energy rather than coal, oil, and gas. The study concludes that until adequate strategies are devised towards the use of renewable energy the region will continue to add and worsen the current climate change menace and other adverse environmental conditions.

Keywords: carbon dioxide, climate change, legislation/law, renewable energy

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Authors: Mayank Mundhra, Chester Rebeiro

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Cryptocurrencies are rapidly finding wide application in areas such as Real Time Gross Settlements and Payments Systems. Ripple is a cryptocurrency that has gained prominence with banks and payment providers. It solves the Byzantine General’s Problem with its Ripple Protocol Consensus Algorithm (RPCA), where each server maintains a list of servers, called Unique Node List (UNL) that represents the network for the server, and will not collectively defraud it. The server believes that the network has come to a consensus when members of the UNL come to a consensus on a transaction. In this paper we improve Ripple to achieve better speed, security, last mile connectivity and ease of use. We implement guidelines and automated systems for building and maintaining UNLs for resilience, robustness, improved security, and efficient information propagation. We enhance the system so as to ensure that each server receives information from across the whole network rather than just from the UNL members. We also introduce the paradigm of UNL overlap as a function of information propagation and the trust a server assigns to its own UNL. Our design not only reduces vulnerabilities such as eclipse attacks, but also makes it easier to identify malicious behaviour and entities attempting to fraudulently Double Spend or stall the system. We provide experimental evidence of the benefits of our approach over the current Ripple scheme. We observe ≥ 4.97x and 98.22x in speedup and success rate for information propagation respectively, and ≥ 3.16x and 51.70x in speedup and success rate in consensus.

Keywords: Ripple, Kelips, unique node list, consensus, information propagation

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Authors: Kaouther Bergaui, Nafaa Reguigui, Charles Gary

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Characterization and the applications of deuterium-deuterium (DD) neutron generator developed by Adelphie technology and acquired by the National Centre of Nuclear Science and Technology (NCNST) were presented in this work. We study the performance of the neutron generator in terms of neutron yield, production efficiency, and the ionic current as a function of the acceleration voltage at various RF powers. We provide the design and optimization of the PGNAA chamber and thus give insight into the capabilities of the planned PGNAA facility. Additional non-destructive techniques were studied employing the DD neutron generator, such as PGNAA and neutron radiography: The PGNAA is used for determining the concentration of 10B in Si and SiO2 matrices by using a germanium detector HPGe and the results obtained are compared with PGNAA system using a Sodium Iodide detector (NaI (Tl)); Neutron radiography facility was tested and simulated, using a camera device CCD and simulated by the Monte Carlo code; and the explosive detection system (EDS) also simulated using the Monte Carlo code. The study allows us to show that the new models of DD neutron generators are feasible and that superior-quality neutron beams could be produced and used for various applications. The feasibility of Boron neutron capture therapy (BNCT) for cancer treatment using a neutron generator was assessed by optimizing Beam Shaping Assembly (BSA) on a phantom using Monte-Carlo (MCNP6) simulations.

Keywords: neutron generator deuterium-deuterium, Monte Carlo method, radiation, neutron flux, neutron activation analysis, born, neutron radiography, explosive detection, BNCT

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Authors: Alam Anshary, Flora Pasaru, Shahabuddin

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The Cocoa Pod Borer (CPB), Conopomorpha cramerella (Snell.) is present on most of the larger cocoa producing islands in Indonesia. Various control measures CPB has been carried out by the farmers, but the results have not been effective. This study aims to determine the effect of application of Beauveria bassiana treatments and pruning technique to the control of CPB in the cocoa plantation people. Research using completely randomized design with 4 treatments and 3 replications, treatment consists of B.bassiana, Pruning, B. bassiana+pruning (Bb + Pr), as well as the control. The results showed that the percentage of PBK attack on cocoa pods in treatment (Bb + Pr) 3.50% the lowest compared to other treatments. CPB attack percentage in treatment B.bassiana 6.15%; pruning 8.75%, and 15.20% control. Results of the analysis of production estimates, the known treatments (Bb + Pr) have the highest production (1.95 tonnes / ha). The model results estimated production is Y= 0,20999 + 0,53968X1 + 0,34298X2+ 0,31410X3 + 0,35629X4 + 0,08345X5 + 0,29732X6. Farm production costs consist of fixed costs and variable costs, fixed costs are costs incurred by the farmer that the size does not affect the results, such as taxes and depreciation of production equipment. Variable costs are costs incurred by farmers who used up in one year cocoa farming activities. The cost of production in farming cocoa without integrated techniques control of CPB is Rp. 9.205.550 million/ha, while the cost of production with integrated techniques control is Rp. 6.666.050 million/ha.

Keywords: cacao, cocoa pod borer, pruning, Beauveria bassiana, production costs

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Authors: Narmeen Ali, Muhammad Arshad

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Cohesion has an exact association with family functioning and enmeshment (togetherness) on one side and disengagement (separateness) on the other. Family cohesion can apprehend as a concerned association that family members have with each other and an affirmation of association inside the family. Family cohesion, assigned as the level of congruity or sympathetic or emotional attachment that relatives have toward each other, and it was seen to be associated with relational well-being and feeling of comfort in the young generation. The cross-sectional research design was used by the researcher to answer the research questions. A stratified sampling technique was used to collect the data from the participants. The data was collected equally from the males and females of different universities and different departments of Lahore, Pakistan. A self-report questionnaire was developed of given literature and which were found to be associated with family cohesion, interpersonal difficulties and mental health problems of university students. The demographic information included age, gender, university’s name, class, family system, parent’s education, parent’s profession, number of siblings and birth order. Correlation shows the negative relation between balanced cohesion and interpersonal difficulties, while interpersonal difficulties have a highly positive relationship with mental health problems. Mental health problems also have a negative correlation with the balanced family cohesion. Gender, family system, depression and anxiety are the significant predictors of interpersonal difficulties scale in university students. And gender showed a significant difference regarding family cohesion and interpersonal difficulty scale, as women reported more interpersonal difficulties than men.

Keywords: family cohesion, interpersonal difficulties, mental health problems, university students

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Authors: Yi-Ying Lin, Su-Guo, Chia-Hao, Ming-Szu Hong

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Objectives: Smoking is a common addictive behavior in teenagers. Long-term smoking is hazardous to health, causes family and social expenditure, and is an important topic that should not be overlooked by academia or the government. The aims of this study are to examine the effectiveness of these courses in terms of teenagers’ knowledge and attitudes towards the hazards of smoking and the effectiveness of their self-efficacy in rejecting smoking. Methods: This study adopted a pre-test post-test design and selected 7th, 8th, 10th, and 11th graders from two junior high schools. Total of 1073 valid questionnaires were collected. The self-completed questionnaire included background information, smoking status of relatives staying with the subject, attitudes of parents towards child smoking, knowledge and attitudes towards smoking, and anti-smoking self-efficacy. Results and clinical applications: Subjects in the experimental group underwent course interventions, which are 'smoking prevention courses,' in the semester. After course intervention, it was found that the intervention showed significant efficacy in terms of knowledge and self-efficacy in rejecting smoking in senior high school students but no efficacy in junior high school. We recommend that this course can be used in normal senior high schools. With regards to junior high schools, smoking prevention courses should be designed to be gamified, or combined with activities with both anti-smoking messages and entertainment at the same time, so that knowledge, attitudes, and self-efficacy can be subconsciously cultivated.

Keywords: adolescent students, smoking knowledge, attitudes, anti-smoking self-efficiency, smoking prevention intervention

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Authors: Lina Vyas, Stuti Rawat

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The COVID-19 outbreak has forced many employees to extensively adopt remote work or, widely known as work from home (WFH) arrangements. During the last two years, both employers and employees have had the opportunity to be increasingly aware of the benefits and drawbacks of WFH. Likewise, it gained the attention of academics from various schools of thought who have been interested in the future of work practices and work-life balance. Additionally, employees might also have various demands regarding their work practices after the pandemic. This study explores the potential of hybrid ways of working in the post-pandemic period by comparing first-timers who (sometimes or always) worked from home during the pandemic with those who did not, in terms of the aspects of work-life balance, work-life interference, job performance and willingness to work from home after the pandemic. The quantitative research approach was adopted. Data were collected via an online questionnaire from employees working from home in Hong Kong during the pandemic. There were one thousand three hundred and twenty-eight responses, but only 1,235 respondents experienced working from home during the pandemic. The findings reveal that 72.2% never had or hardly experienced work from home prior to the pandemic. There were statistically significant differences between first-timers and non-first-timers in work-life balance and work-life interference. The study also found that first-timers who were always working from home during the pandemic would prefer having longer WFH after the pandemic than those who were sometimes working from home. These results would serve as a basis for policy development, enabling policymakers to design appropriate HR policies and amend them to meet the current context of actual employee needs.

Keywords: hybrid working mode, remote working, work from home, work-life balance, workplace

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Authors: Leema Jacob

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The concept of psychological well-being is complex and has familiar use not only in psychology but also in the area of lifespan development. Eudaimonic well-being is finding a purpose and meaning in life, and this depends on both the individual and society, especially during adolescence; the social-cognitive environment can be decisive. The social environment of adolescents, including family, school, and friends, is recognized as an essential context for successful human life. The development of mature social relationships is also undoubtedly important. Theory of Mind is an emerging domain in cognitive neuroscience that involves the ability to attribute mental states to oneself and others. ToM skills training constitutes a new aspect of the adolescent’s social development, including four domains: cognitive ToM, affective ToM, and an inter-intra-personal understanding of social norms. Still, little effort has been made to promote this training as a modality to foster their psychological well-being. This study aims to use the eudaimonic approach to evaluate psychological well-being with a quasi-experimental research design (pre-post-test). The major objective of the study was to identify the effect of ToM skills training on the eudaimonic well-being of adolescents with low social cognition. The data was analyzed to find their effect size from a sample of 74 adolescents from India between 17 and 19 years old. The result revealed that ToM skills training has a positive outcome on the well-being of adolescents post-training. The results are discussed based on the effect of ToM skills training on psychological well-being during adolescence, as well as on the importance of focusing on mental health as a developmental asset that can potentially influence mental well-being in the future.

Keywords: ToM training, adolescents, eudaimonic well-being, social cognition

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Authors: Shirin Shaideh, Nina Shirkhanloo

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Creative public spaces were needed to foster conviviality in an urban form. The conviviality could be enhanced by facilitating variety of opportunities to participate in communal activities and promoting collective experiences. In this regard, The Namik Kemal Square as a major public space of Walled City of Famagusta in North Cyprus was found as the creative public space because it supports collective practices by leisure activities which enclosed the space. The square also utilized creative collaboration such as festivals and outdoor exhibition. Accordingly this paper focuses on the issue of conviviality in urban public space, in the perspective of square, as a major indicator of their success. The survey firstly provides a theoretical framework for understanding conviviality in creative public space to empower collective experience. Secondly it discusses the essential components of conviviality in form of square and finally investigating conviviality and also its determinants in Namik Kemal square. Hence, the main challenges of this study are going to focus on how convivial public spaces impact collective experience, what people expect from a kind of public space, or what they perceive as a good place to be in. Since it seems essential to respond positively, inclusively to the needs of people to socialize in public spaces by involving them in collective and common practices, this article aims to tease out what gives some places personality and conviviality so that we can learn to design, maintain and manage better quality built environment in future.

Keywords: conviviality, creative public space, collective experience, Namik Kemal square

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Authors: Sachin Jain, Daniel Perez-Astudillo, Dunia A. Bachour, Antonio P. Sanfilippo

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The future of solar energy in Qatar is evolving steadily. Hence, high-quality spatial solar radiation data is of the uttermost requirement for any planning and commissioning of solar technology. Generally, two types of solar radiation data are available: satellite data and ground observations. Satellite solar radiation data is developed by the physical and statistical model. Ground data is collected by solar radiation measurement stations. The ground data is of high quality. However, they are limited to distributed point locations with the high cost of installation and maintenance for the ground stations. On the other hand, satellite solar radiation data is continuous and available throughout geographical locations, but they are relatively less accurate than ground data. To utilize the advantage of both data, a product has been developed here which provides spatial continuity and higher accuracy than any of the data alone. The popular satellite databases: National Solar radiation Data Base, NSRDB (PSM V3 model, spatial resolution: 4 km) is chosen here for merging with ground-measured solar radiation measurement in Qatar. The spatial distribution of ground solar radiation measurement stations is comprehensive in Qatar, with a network of 13 ground stations. The monthly average of the daily total Global Horizontal Irradiation (GHI) component from ground and satellite data is used for error analysis. The normalized root means square error (NRMSE) values of 3.31%, 6.53%, and 6.63% for October, November, and December 2019 were observed respectively when comparing in-situ and NSRDB data. The method is based on the Empirical Bayesian Kriging Regression Prediction model available in ArcGIS, ESRI. The workflow of the algorithm is based on the combination of regression and kriging methods. A regression model (OLS, ordinary least square) is fitted between the ground and NSBRD data points. A semi-variogram is fitted into the experimental semi-variogram obtained from the residuals. The kriging residuals obtained after fitting the semi-variogram model were added to NSRBD data predicted values obtained from the regression model to obtain the final predicted values. The NRMSE values obtained after merging are respectively 1.84%, 1.28%, and 1.81% for October, November, and December 2019. One more explanatory variable, that is the ground elevation, has been incorporated in the regression and kriging methods to reduce the error and to provide higher spatial resolution (30 m). The final GHI maps have been created after merging, and NRMSE values of 1.24%, 1.28%, and 1.28% have been observed for October, November, and December 2019, respectively. The proposed merging method has proven as a highly accurate method. An additional method is also proposed here to generate calibrated maps by using regression and kriging model and further to use the calibrated model to generate solar radiation maps from the explanatory variable only when not enough historical ground data is available for long-term analysis. The NRMSE values obtained after the comparison of the calibrated maps with ground data are 5.60% and 5.31% for November and December 2019 month respectively.

Keywords: global horizontal irradiation, GIS, empirical bayesian kriging regression prediction, NSRDB

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Authors: Oluwole Victor Falobi, Lawrence Olusola Ige

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The cardinal drawing force of this study is to examine the influence of audio-visual resources in teaching business subjects in selected secondary schools in IfakoIjaiye Local Government Area of Lagos State, Nigeria. A descriptive survey research design was employed for the study. By using a quantitative research approach and a sample size of 120 students were randomly selected from four public schools. Three research questions with one hypothesis guided the study. Data collected were analysed using frequency, the mean and standard deviation for the research questions, and Pearson Product Moment Correlation PPMC were used to analysed the inferential statistic. Findings from the study revealed that the Influence of audio-visual resources in teaching business subjects in selected secondary schools in IfakoIjaiye Local Government Area of Lagos State is low. It further revealed data the knowledge of teachers on the use of audio-visual resources is high in Ifako Local Government Area. It was recommended that government should create a timely monitoring system in other to check secondary school laboratories and classrooms to replace outdated facilities and also purchase needed facilities for effective teaching and learning to take place.

Keywords: audio-visual resources, business subjects, school, teaching

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Authors: Vincent Ballola, Raymund Dilan, Thelma Palaoag

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The Smart Online Library Catalog System with Query Expansion seeks to address the low usage of the library because of the emergence of the Internet. Library users are not accustomed to catalog systems that need a query to have the exact words without any mistakes for decent results to appear. The graphical user interface of the current system has a rather skewed learning curve for users to adapt with. With a simple graphical user interface inspired by Google, users can search quickly just by inputting their query and hitting the search button. Because of the query expansion techniques incorporated into the new system such as stemming, thesaurus search, and weighted search, users can have more efficient results from their query. The system will be adding the root words of the user's query to the query itself which will then be cross-referenced to a thesaurus database to search for any synonyms that will be added to the query. The results will then be arranged by the number of times the word has been searched. Online queries will also be added to the results for additional references. Users showed notable increases in efficiency and usability due to the familiar interface and query expansion techniques incorporated in the system. The simple yet familiar design led to a better user experience. Users also said that they would be more inclined in using the library because of the new system. The incorporation of query expansion techniques gives a notable increase of results to users that in turn gives them a wider range of resources found in the library. Used books mean more knowledge imparted to the users.

Keywords: query expansion, catalog system, stemming, weighted search, usability, thesaurus search

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Authors: Yu Qin, Wanjiaman Li

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The widespread use of mobile electronic devices increases the complexities of mobile security. This thesis aims to provide a secure communication environment for smartphone users. Some research proves that the one-time pad is one of the securest encryption methods, and that the key distribution problem can be solved by using the QKD (quantum key distribution). The objective of this project is to design an Android APP (application) to exchange several random keys between mobile phones. Inspired by QKD, the developed APP uses the quick response (QR) code as a carrier to dispatch large amounts of one-time keys. After evaluating the performance of APP, it allows the mobile phone to capture and decode 1800 bytes of random data in 600ms. The continuous scanning mode of APP is designed to improve the overall transmission performance and user experience, and the maximum transmission rate of this mode is around 2200 bytes/s. The omnidirectional readability and error correction capability of QR code gives it a better real-life application, and the features of adequate storage capacity and quick response optimize overall transmission efficiency. The security of this APP is guaranteed since QR code is exchanged face-to-face, eliminating the risk of being eavesdropped. Also, the id of QR code is the only message that would be transmitted through the whole communication. The experimental results show this project can achieve superior transmission performance, and the correlation between the transmission rate of the system and several parameters, such as the QR code size, has been analyzed. In addition, some existing technologies and the main findings in the context of the project are summarized and critically compared in detail.

Keywords: one-time pad, QKD (quantum key distribution), QR code, application

Procedia PDF Downloads 142

Authors: C. M. Balaceanu, G. Suciu, C. S. Bosoc, O. Orza, C. Fernandez, Z. Viniczay

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The Internet of Things (IoT) represents the best option for smart vineyard applications, even if it is necessary to integrate the technologies required for the development. This article is based on the research and the results obtained in the DISAVIT project. For Smart Agriculture, the project aims to provide a trustworthy, intelligent, integrated vineyard management solution that is based on the IoT. To have interoperability through the use of a multiprotocol technology (being the future connected wireless IoT) it is necessary to adopt an agnostic approach, providing a reliable environment to address cyber security, IoT-based threats and traceability through blockchain-based design, but also creating a concept for long-term implementations (modular, scalable). The ones described above represent the main innovative technical aspects of this project. The DISAVIT project studies and promotes the incorporation of better management tools based on objective data-based decisions, which are necessary for agriculture adapted and more resistant to climate change. It also exploits the opportunities generated by the digital services market for smart agriculture management stakeholders. The project's final result aims to improve decision-making, performance, and viticulturally infrastructure and increase real-time data accuracy and interoperability. Innovative aspects such as end-to-end solutions, adaptability, scalability, security and traceability, place our product in a favorable situation over competitors. None of the solutions in the market meet every one of these requirements by a unique product being innovative.

Keywords: blockchain, IoT, smart agriculture, vineyard

Procedia PDF Downloads 193

Authors: Justine A. Lloyd

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Since the onset of the Syrian Civil War in 2011, the ancient city of Dura-Europos has faced widespread destruction and looting. The site is one of many places in the country the terrorist group ISIS has specifically targeted, allegedly due to its particular representations of Syrian history and culture. However, looted art and artifacts are the extremist group’s second largest source of income, only after oil. The protection of this site is important to both academics and the millions who have called Syria a home, as it aids in the nation’s sense of identity, reveals developments in the arts, and contributes to humanity’s collective history. At a time when Syria’s culture is being flattened, this sense of cultural expression is especially important to maintain. Creating an awareness of the magnitude of the issue at hand begins with an examination of the rich history of the ancient fortress city. Located on the western bank of the Euphrates River, Dura-Europos contains artifacts dating back to the Hellenistic, Parthian, and Roman periods. Though a great deal of the art and artifacts have remained safe in institutions such as the National Museum of Damascus and the Yale University Art Gallery, hundreds of looting pits and use of heavy machinery on the site has severely set back the investigative progress made by archaeologists over the last century, as well as the prospect of future excavation. Further research draws on the current destruction of the site by both ISIS and opportunists involved with the black market. Because Dura-Europos is located in a war stricken region, the acquisition of data and possibility of immediate action is particularly challenging. Resources gained from local reports, in addition to technology such as satellite imagery, however, have provided a firm starting point for the evaluation of the state of the site. The Syrian Ministry of Culture, UNESCO, and numerous Syrian and global organizations provide insight into the historic city’s past, present issues, and future plans to ensure that the cultural integrity of the site is upheld. Though over seventy percent of Dura-Europos has been completely decimated, this research challenges the notion that physically destroyed sites are lost forever. This paper assesses preventative measures that can take place to ensure the preservation of the site’s art and architecture, including examining possible solutions to the damage, such as digital reconstruction, replication, and distribution of information through exhibitions and other forms of publically accessible information. In order to investigate any possible retribution, research also includes the necessary information pertaining the global laws and regulations dealing with cultural heritage, as it directly affects the ways in which this situation can be dealt with. With the countless experts and citizens dedicated to the importance of cultural heritage, the prospect of honoring and valuing elements of Dura-Europos is possible—whether physically preserved or otherwise.

Keywords: antiquities law, archaeological sites, restitution, Syrian Civil War

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Authors: Abdul Rahim Razalli, Nordin Mamat, Lee Kean Low

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The objective of the study is to examine the acquisition of Bahasa Melayu hand coded and Malaysian Sign Language of hearing impaired children and the factors that influencing the acquisition of Malay language at early intervention. A qualitative research design was chosen to answer two research questions. Two sets of instruments have been used to obtain information of proficiency and factors that influence it. Five children with hearing problems, four teachers and three parents were selected as the respondents through purposive sampling technique. The findings show that pupils with hearing problems who mastered Bahasa Melayu hand coded have better acquisition of Bahasa Melayu as compared to those who acquired Malaysian Sign Language. The study also found that the parents, pupils, teachers and environmental factors have an impact on the acquisition of Bahasa Melayu hand coded. The implications of this study show that early intervention of Bahasa Melayu hand coded and the parents, pupils, teachers and environmental factors do help in the language proficiency of children with hearing problems. A more comprehensive study should be undertaken at a higher level to see the impact on an early intervention program for Malay language acquisition of hearing impaired children.

Keywords: Bahasa Melayu hand coded, Malaysian sign Language, hearing impaired children, early intervention

Procedia PDF Downloads 246

Authors: Cristina Opris, Bogdan Cojocaru, Madalina Tudorache, Simona M. Coman, Vasile I. Parvulescu, Camelia Bala, Bahir Duraki, Jeroen A. Van Bokhoven

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The tremendous achievements in the development of the society concretized by more sophisticated materials and systems are merely based on non-renewable resources. Consequently, after more than two centuries of intensive development, among others, we are faced with the decrease of the fossil fuel reserves, an increased impact of the greenhouse gases on the environment, and economic effects caused by the fluctuations in oil and mineral resource prices. The use of biomass may solve part of these problems, and recent analyses demonstrated that from the perspective of the reduction of the emissions of carbon dioxide, its valorization may bring important advantages conditioned by the usage of genetic modified fast growing trees or wastes, as primary sources. In this context, the abundance and complex structure of lignin may offer various possibilities of exploitation. However, its transformation in fuels or chemicals supposes a complex chemistry involving the cleavage of C-O and C-C bonds and altering of the functional groups. Chemistry offered various solutions in this sense. However, despite the intense work, there are still many drawbacks limiting the industrial application. Thus, the proposed technologies considered mainly homogeneous catalysts meaning expensive noble metals based systems that are hard to be recovered at the end of the reaction. Also, the reactions were carried out in organic solvents that are not acceptable today from the environmental point of view. To avoid these problems, the concept of this work was to investigate the synthesis of superparamagnetic core shell catalysts for the fragmentation of lignin directly in the aqueous phase. The magnetic nanoparticles were covered with a nanoshell of an oxide (niobia) with a double role: to protect the magnetic nanoparticles and to generate a proper (acidic) catalytic function and, on this composite, cobalt nanoparticles were deposed in order to catalyze the C-C bond splitting. With this purpose, we developed a protocol to prepare multifunctional and magnetic separable nano-composite Co@Nb2O5@Fe3O4 catalysts. We have also established an analytic protocol for the identification and quantification of the fragments resulted from lignin depolymerization in both liquid and solid phase. The fragmentation of various lignins occurred on the prepared materials in high yields and with very good selectivity in the desired fragments. The optimization of the catalyst composition indicated a cobalt loading of 4wt% as optimal. Working at 180 oC and 10 atm H2 this catalyst allowed a conversion of lignin up to 60% leading to a mixture containing over 96% in C20-C28 and C29-C37 fragments that were then completely fragmented to C12-C16 in a second stage. The investigated catalysts were completely recyclable, and no leaching of the elements included in the composition was determined by inductively coupled plasma optical emission spectrometry (ICP-OES).

Keywords: superparamagnetic core-shell catalysts, environmental production of fuels, renewable lignin, recyclable catalysts

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