Search results for: dynamics of knowledge and it
9282 Using Arellano-Bover/Blundell-Bond Estimator in Dynamic Panel Data Analysis – Case of Finnish Housing Price Dynamics
Authors: Janne Engblom, Elias Oikarinen
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A panel dataset is one that follows a given sample of individuals over time, and thus provides multiple observations on each individual in the sample. Panel data models include a variety of fixed and random effects models which form a wide range of linear models. A special case of panel data models are dynamic in nature. A complication regarding a dynamic panel data model that includes the lagged dependent variable is endogeneity bias of estimates. Several approaches have been developed to account for this problem. In this paper, the panel models were estimated using the Arellano-Bover/Blundell-Bond Generalized method of moments (GMM) estimator which is an extension of the Arellano-Bond model where past values and different transformations of past values of the potentially problematic independent variable are used as instruments together with other instrumental variables. The Arellano–Bover/Blundell–Bond estimator augments Arellano–Bond by making an additional assumption that first differences of instrument variables are uncorrelated with the fixed effects. This allows the introduction of more instruments and can dramatically improve efficiency. It builds a system of two equations—the original equation and the transformed one—and is also known as system GMM. In this study, Finnish housing price dynamics were examined empirically by using the Arellano–Bover/Blundell–Bond estimation technique together with ordinary OLS. The aim of the analysis was to provide a comparison between conventional fixed-effects panel data models and dynamic panel data models. The Arellano–Bover/Blundell–Bond estimator is suitable for this analysis for a number of reasons: It is a general estimator designed for situations with 1) a linear functional relationship; 2) one left-hand-side variable that is dynamic, depending on its own past realizations; 3) independent variables that are not strictly exogenous, meaning they are correlated with past and possibly current realizations of the error; 4) fixed individual effects; and 5) heteroskedasticity and autocorrelation within individuals but not across them. Based on data of 14 Finnish cities over 1988-2012 differences of short-run housing price dynamics estimates were considerable when different models and instrumenting were used. Especially, the use of different instrumental variables caused variation of model estimates together with their statistical significance. This was particularly clear when comparing estimates of OLS with different dynamic panel data models. Estimates provided by dynamic panel data models were more in line with theory of housing price dynamics.Keywords: dynamic model, fixed effects, panel data, price dynamics
Procedia PDF Downloads 15109281 Molecular Dynamics Simulation of the Effect of the Solid Gas Interface Nanolayer on Enhanced Thermal Conductivity of Copper-CO2 Nanofluid
Authors: Zeeshan Ahmed, Ajinkya Sarode, Pratik Basarkar, Atul Bhargav, Debjyoti Banerjee
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The use of CO2 in oil recovery and in CO2 capture and storage is gaining traction in recent years. These applications involve heat transfer between CO2 and the base fluid, and hence, there arises a need to improve the thermal conductivity of CO2 to increase the process efficiency and reduce cost. One way to improve the thermal conductivity is through nanoparticle addition in the base fluid. The nanofluid model in this study consisted of copper (Cu) nanoparticles in varying concentrations with CO2 as a base fluid. No experimental data are available on thermal conductivity of CO2 based nanofluid. Molecular dynamics (MD) simulations are an increasingly adopted tool to perform preliminary assessments of nanoparticle (NP) fluid interactions. In this study, the effect of the formation of a nanolayer (or molecular layering) at the gas-solid interface on thermal conductivity is investigated using equilibrium MD simulations by varying NP diameter and keeping the volume fraction (1.413%) of nanofluid constant to check the diameter effect of NP on the nanolayer and thermal conductivity. A dense semi-solid fluid layer was seen to be formed at the NP-gas interface, and the thickness increases with increase in particle diameter, which also moves with the NP Brownian motion. Density distribution has been done to see the effect of nanolayer, and its thickness around the NP. These findings are extremely beneficial, especially to industries employed in oil recovery as increased thermal conductivity of CO2 will lead to enhanced oil recovery and thermal energy storage.Keywords: copper-CO2 nanofluid, molecular dynamics simulation, molecular interfacial layer, thermal conductivity
Procedia PDF Downloads 3389280 Asset Liability Modelling for Pension Funds by Introducing Leslie Model for Population Dynamics
Authors: Kristina Sutiene, Lina Dapkute
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The paper investigates the current demographic trends that exert the sustainability of pension systems in most EU regions. Several drivers usually compose the demographic challenge, coming from the structure and trends of population in the country. As the case of research, three main variables of demographic risk in Lithuania have been singled out and have been used in making up the analysis. Over the last two decades, the country has presented a peculiar demographic situation characterized by pessimistic fertility trends, negative net migration rate and rising life expectancy that make the significant changes in labor-age population. This study, therefore, sets out to assess the relative impact of these risk factors both individually and in aggregate, while assuming economic trends to evolve historically. The evidence is presented using data of pension funds that operate in Lithuania and are financed by defined-contribution plans. To achieve this goal, the discrete-time pension fund’s value model is developed that reflects main operational modalities: contribution income from current participants and new entrants, pension disbursement and administrative expenses; it also fluctuates based on returns from investment activity. Age-structured Leslie population dynamics model has been integrated into the main model to describe the dynamics of fertility, migration and mortality rates upon age. Validation has concluded that Leslie model adequately fits the current population trends in Lithuania. The elasticity of pension system is examined using Loimaranta efficiency as a measure for comparison of plausible long-term developments of demographic risks. With respect to the research question, it was found that demographic risks have different levels of influence on future value of aggregated pension funds: The fertility rates have the highest importance, while mortality rates give only a minor impact. Further studies regarding the role of trying out different economic scenarios in the integrated model would be worthwhile.Keywords: asset liability modelling, Leslie model, pension funds, population dynamics
Procedia PDF Downloads 2709279 Investigating Iraqi EFL University Students' Productive Knowledge of Grammatical Collocations in English
Authors: Adnan Z. Mkhelif
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Grammatical collocations (GCs) are word combinations containing a preposition or a grammatical structure, such as an infinitive (e.g. smile at, interested in, easy to learn, etc.). Such collocations tend to be difficult for Iraqi EFL university students (IUS) to master. To help address this problem, it is important to identify the factors causing it. This study aims at investigating the effects of L2 proficiency, frequency of GCs and their transparency on IUSs’ productive knowledge of GCs. The study involves 112 undergraduate participants with different proficiency levels, learning English in formal contexts in Iraq. The data collection instruments include (but not limited to) a productive knowledge test (designed by the researcher using the British National Corpus (BNC)), as well as the grammar part of the Oxford Placement Test (OPT). The study findings have shown that all the above-mentioned factors have significant effects on IUSs’ productive knowledge of GCs. In addition to establishing evidence of which factors of L2 learning might be relevant to learning GCs, it is hoped that the findings of the present study will contribute to more effective methods of teaching that can better address and help overcome the problems IUSs encounter in learning GCs. The study is thus hoped to have significant theoretical and pedagogical implications for researchers, syllabus designers as well as teachers of English as a foreign/second language.Keywords: corpus linguistics, frequency, grammatical collocations, L2 vocabulary learning, productive knowledge, proficiency, transparency
Procedia PDF Downloads 2529278 Nature of Traffic Robbery Victimisation Experience 2015-2023
Authors: Idenyi Goshen Peter, Oludayo Tade
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Traffic robbery is a prevalent issue in Lagos State, impacting commuters and transport workers, necessitating an examination of victimization experiences and offender-victim dynamics. The research aim is to investigate the nature of traffic robbery victimization experiences, strategies employed by offenders, and the extent of the crime as reported in newspapers. Utilizing content analysis, the study examines 167 traffic robbery cases from 2015 to 2023 reported in five newspapers using the routine activity theory to understand the dynamics between offenders and victims. The research discusses the victimization experience and convergence of the offenders and victims, it documents the extent of the crime as captured by various newspapers (Vanguard, Punch. Tribune, Sun and Guardian ), and it also interrogates the strategies, methods deployed by traffic robbers. The study addresses the nature, strategies, and extent of traffic robbery victimization experiences, shedding light on the dynamics of the crime over an eight-year period. The paper implored secondary research from newspaper publications, and also content analysis for the research. Routine activity theory was used to explain the phenomenon that exists between the offender and the victim. Consequently, the common method used by offenders is dispossessing victims of their valuables, leading to fear-driven victim experiences, with spikes in incidents observed in June and December, particularly in Vanguard and Punch publications.Keywords: traffic robbery, victimisation experience, offender, routine activity
Procedia PDF Downloads 259277 Rates of Hematophagous Ectoparasite Consumption during Grooming by an Endemic Madagascar Fruit Bat
Authors: Riana V. Ramanantsalama, Aristide Andrianarimisa, Achille P. Raselimanana, Steven M. Goodman
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Few details are available on the consumption of ectoparasites, specifically bat flies (Diptera: Nycteribiidae and Streblidae), by their chiropteran hosts while grooming. Such details could provide information on the dynamics of host-parasite interactions. This study presents data on ectoparasite ingestion rates for an endemic Malagasy fruit bat (Pteropodidae: Rousettus madagascariensis) occupying a cave day roost colony in northern Madagascar. Using quantified behavioral analyses, grooming and associated ingestion rates were measured from infrared videos taken in close proximity to day-roosting bats. The recorded individual bats could be visually identified to age (adult, juvenile) and sex (male, female), allowing analyses of the proportion of time these different classes allocated to consuming ectoparasites via auto-grooming (self) or allo-grooming (intraspecific) per 10 min video recording session. These figures could then be extrapolated to estimates of individual daily consumption rates. Based on video recordings, adults spent significantly more time auto-grooming and allo-grooming than juveniles. The latter group was not observed consuming ectoparasites. Grooming rates and the average number of ectoparasites consumed per day did not differ between adult males and females. The mean extrapolated number consumed on a daily basis for individual adults was 37 ectoparasites. When these figures are overlaid on the estimated number of adult Rousettus occurring at the roost site during the dry season, the projected daily consumption rate was 57,905 ectoparasites. To the best knowledge of the authors of this study, the details presented here represent the first quantified data on bat consumption rates of their ectoparasites, specifically dipterans. These results provide new insights into host-parasite predation dynamics. More research is needed to explore the mechanism zoonotic diseases isolated from bat flies might be transmitted to their bat hosts, specifically those pathogens that can be communicated via an oral route.Keywords: diptera, host-parasite interactions, Madagascar, nycteribiidae, pteropodidae, Rousettus madagascariensis
Procedia PDF Downloads 1479276 A Multi-Site Knowledge Attitude and Practice Survey of Ebola Virus Disease (EVD) in Nigeria
Authors: Ilyasu G., Ogoina D., Otu AA, Muhammed FD, Ebenso B., Otokpa D., Rotifa S., Tuduo-Wisdom O., Habib AG
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Background: The 2014 Ebola Virus Disease (EVD) outbreak was characterized by fear, misconceptions and irrational behaviors. We conducted a knowledge attitude and practice survey of EVD in Nigeria to inform the institution of effective control measures. Methods: Between July 30th and September 30th 2014, a cross-sectional study on knowledge, attitude and practice (KAP) of Ebola Virus Disease (EVD) was undertaken among adults of the general population and healthcare workers (HCW) in three states of Nigeria, including Kano, Cross River and Bayelsa states. Demographic information and data on KAP were obtained using a self-administered standardized questionnaire. The percentage KAP scores were categorized as good and poor. Independent predictors of good knowledge of EVD were ascertained using a binary logistic regression model. Results: Out of 1035 study participants with a median age of 32 years, 648 (62.6%) were males, 846 (81.7%) had tertiary education and 441 (42.6%) were HCW. There were 218, 239 and 578 respondents from Bayelsa, Cross Rivers, and Kano states, respectively. The overall median percentage KAP scores and interquartile ranges (IQR) were 79.46% (15.07%), 95.0% (33.33%), and 49.95% (37.50%), respectively. Out of the 1035 respondents, 470 (45.4%), 544(52.56%), and 252 (24.35%) had good KAP of EVD defined using 80%, 90%, and 70% score cut-offs, respectively. Independent predictors of good knowledge of EVD were a HCW (Odds Ratio-OR-2.89, 95% Confidence interval-CI of 1.41-5.90), reporting ‘moderate to high fear of EVD’ (OR-2.15, 95% CI-1.47-3.13) and ‘willingness to modify habit’ (OR-1.68, 95% CI-1.23-2.30). Conclusion: Our results reveal suboptimal EVD-related knowledge, attitude and practice among adults in Nigeria. To effectively control future outbreaks of EVD in Nigeria, there is a need to institute public sensitization programs that improve understanding of EVD and address EVD-related myths and misconceptions, especially among the general population.Keywords: Ebola, health care worker, knowledge, attitude
Procedia PDF Downloads 2869275 A Dissipative Particle Dynamics Study of a Capsule in Microfluidic Intracellular Delivery System
Authors: Nishanthi N. S., Srikanth Vedantam
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Intracellular delivery of materials has always proved to be a challenge in research and therapeutic applications. Usually, vector-based methods, such as liposomes and polymeric materials, and physical methods, such as electroporation and sonoporation have been used for introducing nucleic acids or proteins. Reliance on exogenous materials, toxicity, off-target effects was the short-comings of these methods. Microinjection was an alternative process which addressed the above drawbacks. However, its low throughput had hindered its adoption widely. Mechanical deformation of cells by squeezing them through constriction channel can cause the temporary development of pores that would facilitate non-targeted diffusion of materials. Advantages of this method include high efficiency in intracellular delivery, a wide choice of materials, improved viability and high throughput. This cell squeezing process can be studied deeper by employing simple models and efficient computational procedures. In our current work, we present a finite sized dissipative particle dynamics (FDPD) model to simulate the dynamics of the cell flowing through a constricted channel. The cell is modeled as a capsule with FDPD particles connected through a spring network to represent the membrane. The total energy of the capsule is associated with linear and radial springs in addition to constraint of the fixed area. By performing detailed simulations, we studied the strain on the membrane of the capsule for channels with varying constriction heights. The strain on the capsule membrane was found to be similar though the constriction heights vary. When strain on the membrane was correlated to the development of pores, we found higher porosity in capsule flowing in wider channel. This is due to localization of strain to a smaller region in the narrow constriction channel. But the residence time of the capsule increased as the channel constriction narrowed indicating that strain for an increased time will cause less cell viability.Keywords: capsule, cell squeezing, dissipative particle dynamics, intracellular delivery, microfluidics, numerical simulations
Procedia PDF Downloads 1419274 KAP Study on Breast Cancer Among Women in Nirmala Educational Institutions-A Prospective Observational Study
Authors: Shaik Asha Begum, S. Joshna Rani, Shaik Abdul Rahaman
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INTRODUCTION: Breast cancer is a disease that creates in breast cells. "KAP" study estimates the Knowledge, Attitude, and Practices of a local area. More than 1.5 million ladies (25% of all ladies with malignancy) are determined to have bosom disease consistently all through the world. Understanding the degrees of Knowledge, Attitude and Practice will empower a more effective cycle of mindfulness creation as it will permit the program to be custom-made all the more properly to the necessities of the local area. OBJECTIVES: The objective of this study is to assess the knowledge on signs and symptoms, risk factors, provide awareness on the practicing of the early detection techniques of breast cancer and provide knowledge on the overall breast cancer including preventive techniques. METHODOLOGY: This is an expressive cross-sectional investigation. This investigation of KAP was done in the Nirmala Educational Institutions from January to April 2021. A total of 300 participants are included from women students in pharmacy graduates & lecturers, and also from graduates other than the pharmacy. The examiners are taken from the BCAM (Breast Cancer Awareness Measure), tool compartment (Version 2). RESULT: According to the findings of the study, the majority of the participants were not well informed about breast cancer. A lump in the breast was the most commonly mentioned sign of breast cancer, followed by pain in the breast or nipple. The percentage of knowledge related to the breast cancer risk factors was also very less. The correct answers for breast cancer risk factors were radiation exposure (58.20 percent), a positive family history (47.6 percent), obesity (46.9 percent), a lack of physical activity (43.6 percent), and smoking (43.2 percent). Breast cancer screening, on the other hand, was uncommon (only 30 and 11.3 percent practiced clinical breast examination and mammography respectively). CONCLUSION: In this study, the knowledge on the signs and symptoms, risk factors of breast cancer - pharmacy graduates have more knowledge than the non-pharmacy graduates but in the preventive techniques and early detective tools of breast cancer -had poor knowledge in the pharmacy and non-pharmacy graduate. After the awareness program, pharmacy and non-pharmacy graduates got supportive knowledge on the preventive techniques and also practiced the early detective techniques of breast cancer.Keywords: breast cancer, mammography, KAP study, early detection
Procedia PDF Downloads 1389273 A Statistical Model for the Dynamics of Single Cathode Spot in Vacuum Cylindrical Cathode
Authors: Po-Wen Chen, Jin-Yu Wu, Md. Manirul Ali, Yang Peng, Chen-Te Chang, Der-Jun Jan
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Dynamics of cathode spot has become a major part of vacuum arc discharge with its high academic interest and wide application potential. In this article, using a three-dimensional statistical model, we simulate the distribution of the ignition probability of a new cathode spot occurring in different magnetic pressure on old cathode spot surface and at different arcing time. This model for the ignition probability of a new cathode spot was proposed in two typical situations, one by the pure isotropic random walk in the absence of an external magnetic field, other by the retrograde motion in external magnetic field, in parallel with the cathode surface. We mainly focus on developed relationship between the ignition probability density distribution of a new cathode spot and the external magnetic field.Keywords: cathode spot, vacuum arc discharge, transverse magnetic field, random walk
Procedia PDF Downloads 4349272 A Strength Weaknesses Opportunities and Threats Analysis of Socialisation Externalisation Combination and Internalisation Modes in Knowledge Management Practice: A Systematic Review of Literature
Authors: Aderonke Olaitan Adesina
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Background: The paradigm shift to knowledge, as the key to organizational innovation and competitive advantage, has made the management of knowledge resources in organizations a mandate. A key component of the knowledge management (KM) cycle is knowledge creation, which is researched to be the result of the interaction between explicit and tacit knowledge. An effective knowledge creation process requires the use of the right model. The SECI (Socialisation, Externalisation, Combination, and Internalisation) model, proposed in 1995, is attested to be a preferred model of choice for knowledge creation activities. The model has, however, been criticized by researchers, who raise their concern, especially about its sequential nature. Therefore, this paper reviews extant literature on the practical application of each mode of the SECI model, from 1995 to date, with a view to ascertaining the relevance in modern-day KM practice. The study will establish the trends of use, with regards to the location and industry of use, and the interconnectedness of the modes. The main research question is, for organizational knowledge creation activities, is the SECI model indeed linear and sequential? In other words, does the model need to be reviewed in today’s KM practice? The review will generate a compendium of the usage of the SECI modes and propose a framework of use, based on the strength weaknesses opportunities and threats (SWOT) findings of the study. Method: This study will employ the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology to investigate the usage and SWOT of the modes, in order to ascertain the success, or otherwise, of the sequential application of the modes in practice from 1995 to 2019. To achieve the purpose, four databases will be explored to search for open access, peer-reviewed articles from 1995 to 2019. The year 1995 is chosen as the baseline because it was the year the first paper on the SECI model was published. The study will appraise relevant peer-reviewed articles under the search terms: SECI (or its synonym, knowledge creation theory), socialization, externalization, combination, and internalization in the title, abstract, or keywords list. This review will include only empirical studies of knowledge management initiatives in which the SECI model and its modes were used. Findings: It is expected that the study will highlight the practical relevance of each mode of the SECI model, the linearity or not of the model, the SWOT in each mode. Concluding Statement: Organisations can, from the analysis, determine the modes of emphasis for their knowledge creation activities. It is expected that the study will support decision making in the choice of the SECI model as a strategy for the management of organizational knowledge resources, and in appropriating the SECI model, or its remodeled version, as a theoretical framework in future KM research.Keywords: combination, externalisation, internalisation, knowledge management, SECI model, socialisation
Procedia PDF Downloads 3589271 Investigating Teachers’ Confidence and Beliefs in Using Technology in Teaching Mathematics in Rwandan Secondary Schools
Authors: Odette Umugiraneza, Etienne Nzaramyimana
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Confidence and beliefs are the main contributors to the improvement of teachers’ mathematical knowledge. The objective of this study was to investigate teachers’ confidence and beliefs towards technology use in teaching mathematics subjects in the Musanze District. The data were collected using closed and open questions. These were distributed to 118 secondary school senior 1 to 6 mathematics teachers in Musanze district. The findings revealed that the teachers’ confidence about the use of technology in teaching mathematics needs improvement. Apart from confidence, almost a third of the teachers convoyed negative beliefs that technology plays great importance in promoting the understanding of mathematics. Teachers as knowledge transmitters are required to join various professional courses towards technology integration in the teaching of mathematics, to improve the effectiveness of teaching and learning.Keywords: knowledge, technology, teachers’ confidence, beliefs, barriers of technology use
Procedia PDF Downloads 1269270 Effects of an Educational Program on Nurses Knowledge and Practice Related to Hepatitis-B: Pre-Experimental Design
Authors: R. S. Mehta, G. N. Mandal
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Hepatitis-B is the major infectious disease of mankind. In Nepal it is reported that more than 4.3% of Nepalese population at any time in their life has been infected with Hepatitis-B virus (HBV). The objective of this study was to evaluate the effectiveness of planned educational programme regarding knowledge and practice of hepatitis-B among the nurses working at medical units of BPKIHS. Pre-experimental research design was used to conduct the study among the nurses working in medical units of BPKIHS. Total 40 nurses were included in the pre-test and 34 in the post-test. The education intervention was arranged on 24th May 2012 from 2:15 pm to 4:45 pm i.e. two and half hours. After two weeks of education intervention post-test was conducted. Most of the participants (60%) were of the age group of 18-22 years, Hindu (82.5%), and unmarried (65%). After education intervention there is significant differences in knowledge on the components of Hepatitis-B at 0.05 level of significance. There is no difference in the attitude components after post-test except the component patient contaminated with Hepatitis-B must be called as the last patient (p=0.035). It can conclude that hepatitis-B educational program improved knowledge and practice among the nurses.Keywords: educational program, Hepatitis-B, pre-experimental design, medical units
Procedia PDF Downloads 3579269 Drivers and Barriers to the Acceptability of a Human Milk Bank Among Malaysians: A Cross Sectional Study
Authors: Kalaashini Ramachandran, Maznah Dahlui, Nik Daliana Nik Farid
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WHO recommends all babies to be exclusively breastfed and donor milk is the next best alternative in the absence of mother’s own milk. The establishment of a human milk bank (HMB) is still being debated due to religious concerns in Malaysia leading to informal milk sharing practices, but little is known on the knowledge, attitude and perception of women towards HMB and its benefits. This study hypothesizes that there is no association between knowledge and attitude and the acceptance towards the establishment of human milk bank among Malaysian women and healthcare providers. The aim of this study is to determine the drivers and barriers among Malaysian towards the acceptance of an HMB. A cross-sectional study with 367 participants was enrolled within a period of 3 months to answer an online self-administered questionnaire. Data on sociodemographic, knowledge on breastfeeding benefits, knowledge and attitude on HMB and its specific issues were analyzed in terms of frequency and then proceed to multiple logistic regression. Majority of the respondents are of Islamis religion (73.3%), have succeesfully completed their tertiary education (82.8%), and are employed (70.8%). Only 55.9% of respondents have heard of an HMB stating internet as their main source of information but a higher prevalence is agreeable to the establishment of a human milk bank (67.8%). Most respondents have a good score on knowledge of breastfeeding benefits and on HMB specific issues (70% and 54.2% respectively) while 63.8% of them have a positive attitude towards HMB. In the multivariate analysis, mothers with a good score on general knowledge of breastfeeding (AOR: 1.715) were more likely to accept the establishment of an HMB while Islamic religion was negatively associated with its establishment (AOR:0.113). This study has found a high prevalence rate of mothers who are willing to accept the establishment of an HMB. This action can be potentially shaped by educating mothers on the benefits of breastfeeding as well as addressing their religious concerns so the establishment of a religiously abiding HMB in Malaysia may be accepted without compromising their belief or the health benefit of donor milk.Keywords: acceptability, attitude, human milk bank, knowledge
Procedia PDF Downloads 1039268 Numerical Study of Heat Transfer in Square Duct with Turbulators
Authors: M. H. Alhajeri, Hamad M. Alhajeri, A. H. Alenezi
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Computational fluid dynamics (CFD) investigation of heat transfer in U-duct with turbulators is presented in this paper. The duct passages used to cool internally the blades in gas turbine. The study is focused in the flow behavior and the Nusselt number (Nu) distributions. The model of the u-duct contains two square legs that are connected by 180* turn. Four turbulators are located in each surface of the leg and distributed in a staggered arrangement. The turbulator height and width are equal to 0.1 of the duct width, and the turbulator height is 0.1 of the distance between the turbulators. The Reynolds number (Re) used in this study is 95000 and the inlet velocity is 10 m/s. It was noticed that, after the flow resettles from the interruptions generated by the first turbulator or the turn, the flow construct two eddies, one large and the other is small after and before the turbulator, respectively. The maximum values of the Nu are found at a distance of approximately one turbulator width w before of the flow reattachment point.Keywords: computational fluid dynamics, CFD, rib, heat transfer, blade
Procedia PDF Downloads 1519267 Knowledge, Attitudes, and Practices regarding Anthrax among Community Members, Health and Veterinary Workers in Maragua, Kenya
Authors: Isaiah Chacha, Samuel Arimi, Andrew Thaiya
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Background: This study was conducted to assess knowledge, attitudes and practices regarding anthrax in Maragua, Kenya to provide baseline information to design interventions. Methods: A cross sectional survey was conducted among head of households, health and veterinary workers in Maragua Sub-county in August and September 2014. Administered questionnaires were used to collect data from household members and a key informant interview held with health and veterinary workers. Multi stage sampling was used to obtain participants’ knowledge, attitudes and practices. Questions were scored and descriptively analyzed using Excel spreadsheet then exported to GenStat Discovery Edition 4. Results: A total of 293 community members were recruited in this study. The overall level of knowledge was 77.9% of all community members regarding cause, transmission, symptoms and prevention of the disease in both humans and animals. Majority of the participants (96.3%) had heard about anthrax. A total of 99 (33.8%) correspondents had seen a person with anthrax and 75.1% think that anthrax is a very serious disease in the area. Of the interviewed correspondents, 14.3% of them have had their animals (mostly cattle) suffer from anthrax while 15.7% had either suffered from anthrax or have had their family member who suffered from anthrax. Conclusion: The study findings indicate above average knowledge on cause, symptoms, transmission and prevention of anthrax among community members in humans and animals. Practices in this study were still risk among community members. Veterinary and Medical health planners should design anthrax awareness interventions as a team targeting to reach these communities and the public through barazas, radio, CHW and other communication channel on a regular basis.Keywords: anthrax, attitudes, Kenya, knowledge, Maragua, practices
Procedia PDF Downloads 3189266 The Effects of the Aspect Ratio of a Flexible Cylinder on the Vortex Dynamics
Authors: Abouzar Kaboudian, Ravi Chaithanya Mysa, Boo Cheong Khoo, Rajeev Kumar Jaiman
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The vortex structures observed in the wake of a flexible cylinder can be significantly different from those of a traditional vibrating, spring mounted, rigid cylinder. These differences can significantly affect the VIV characteristics of the flow and subsequently the VIV response of the cylindrical structures. In this work, we present how the aspect ratio of a flexible cylinder can change the vortex structures in its wake. We will discuss different vortex dynamics which can be observed in the wake of the vibrating flexible cylinder, and how they can affect the vibrational response of the cylinder. Moreover, we will study the transition of these structures versus the aspect ratio of the flexible cylinder. We will discuss how these transitions affect the in-line and transverse forces on the structure. In the end, we will provide general guidelines on the minimum acceptable aspect ratio for the offshore riser studies which may have grave implications for future numerical and experimental works.Keywords: aspect ratio, flexible cylinder, vortex-shedding, VIV
Procedia PDF Downloads 4889265 Analysis of Nonlinear Bertrand Duopoly Game with Heterogeneous Players
Authors: Jixiang Zhang
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A dynamic of Bertrand duopoly game is analyzed, where players use different production methods and choose their prices with bounded rationality. The equilibriums of the corresponding discrete dynamical systems are investigated. The stability conditions of Nash equilibrium under a local adjustment process are studied. The stability conditions of Nash equilibrium under a local adjustment process are studied. The stability of Nash equilibrium, as some parameters of the model are varied, gives rise to complex dynamics such as cycles of higher order and chaos. On this basis, we discover that an increase of adjustment speed of bounded rational player can make Bertrand market sink into the chaotic state. Finally, the complex dynamics, bifurcations and chaos are displayed by numerical simulation.Keywords: Bertrand duopoly model, discrete dynamical system, heterogeneous expectations, nash equilibrium
Procedia PDF Downloads 4079264 Knowledge Reactor: A Contextual Computing Work in Progress for Eldercare
Authors: Scott N. Gerard, Aliza Heching, Susann M. Keohane, Samuel S. Adams
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The world-wide population of people over 60 years of age is growing rapidly. The explosion is placing increasingly onerous demands on individual families, multiple industries and entire countries. Current, human-intensive approaches to eldercare are not sustainable, but IoT and AI technologies can help. The Knowledge Reactor (KR) is a contextual, data fusion engine built to address this and other similar problems. It fuses and centralizes IoT and System of Record/Engagement data into a reactive knowledge graph. Cognitive applications and services are constructed with its multiagent architecture. The KR can scale-up and scaledown, because it exploits container-based, horizontally scalable services for graph store (JanusGraph) and pub-sub (Kafka) technologies. While the KR can be applied to many domains that require IoT and AI technologies, this paper describes how the KR specifically supports the challenging domain of cognitive eldercare. Rule- and machine learning-based analytics infer activities of daily living from IoT sensor readings. KR scalability, adaptability, flexibility and usability are demonstrated.Keywords: ambient sensing, AI, artificial intelligence, eldercare, IoT, internet of things, knowledge graph
Procedia PDF Downloads 1759263 Conception and Misconceptions About Mental Health in Gwafan Community of Jos North Nigeria
Authors: Tabitha D. Hussein, Arigu M. Sunday
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This paper is an attempt to gauge the conception and misconception of mental health in the Gwafan community, Jos North Plateau State, Nigeria (West Africa), to ascertain which side of the scale the pendulum swings. Mental health education and awareness are necessary for healthy community development. However, in a society such as ours in Nigeria (Africa) that is not knowledge-based, it is easy for people to embrace hearsay, speculations, superstition, and the supernatural. The objectives of this paper are two folds: first, to examine the level of awareness of the people on mental health, or the lack of it; second, to ascertain their access to mental health services and good practices. The methodology adopted is qualitative research, and the instrument used is T-test related. The findings include, first, the fact that a larger population has misconceptions about Mental Health. Second, this misconception is a result of a lack of basic knowledge of Mental Health. Based on the aforementioned, the paper recommends that there is a need for more Mental Health Education among the populace and access to Mental Health services and practices (Preventative and Curative). The paper concludes that in a society that is not knowledgebase, every attempt should be made to shift people’s mindset from superstitious knowledge to evidence-based knowledge, which can empower them to make informed decisions not only on mental Health but on associative Health issues that can aid their wellbeing, livelihood and sustainable development as a whole.Keywords: conceptions, misconceptions, mental health, knowledge, superstition, service delivery
Procedia PDF Downloads 509262 Molecular Dynamics Simulations of the Structural, Elastic and Thermodynamic Properties of Cubic GaBi
Authors: M. Zemouli, K. Amara, M. Elkeurti, Y. Benallou
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We present the molecular dynamic simulations results of the structural and dynamical properties of the zinc-blende GaBi over a wide range of temperature (300-1000) K. Our simulation where performed in the framework of the three-body Tersoff potential, which accurately reproduces the lattice constants and elastic constants of the GaBi. A good agreement was found between our calculated results and the available theoretical data of the lattice constant, the bulk modulus and the cohesive energy. Our study allows us to predict the thermodynamic properties such as the specific heat and the lattice thermal expansion. In addition, this method allows us to check its ability to predict the phase transition of this compound. In particular, the transition pressure to the rock-salt phase is calculated and the results are compared with other available works.Keywords: Gallium compounds, molecular dynamics simulations, interatomic potential thermodynamic properties, structural phase transition
Procedia PDF Downloads 4469261 Molecular Dynamics Simulation of Realistic Biochar Models with Controlled Microporosity
Authors: Audrey Ngambia, Ondrej Masek, Valentina Erastova
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Biochar is an amorphous carbon-rich material generated from the pyrolysis of biomass with multifarious properties and functionality. Biochar has shown proven applications in the treatment of flue gas and organic and inorganic pollutants in soil and water/wastewater as a result of its multiple surface functional groups and porous structures. These properties have also shown potential in energy storage and carbon capture. The availability of diverse sources of biomass to produce biochar has increased interest in it as a sustainable and environmentally friendly material. The properties and porous structures of biochar vary depending on the type of biomass and high heat treatment temperature (HHT). Biochars produced at HHT between 400°C – 800°C generally have lower H/C and O/C ratios, higher porosities, larger pore sizes and higher surface areas with temperature. While all is known experimentally, there is little knowledge on the porous role structure and functional groups play on processes occurring at the atomistic scale, which are extremely important for the optimization of biochar for application, especially in the adsorption of gases. Atomistic simulations methods have shown the potential to generate such amorphous materials; however, most of the models available are composed of only carbon atoms or graphitic sheets, which are very dense or with simple slit pores, all of which ignore the important role of heteroatoms such as O, N, S and pore morphologies. Hence, developing realistic models that integrate these parameters are important to understand their role in governing adsorption mechanisms that will aid in guiding the design and optimization of biochar materials for target applications. In this work, molecular dynamics simulations in the isobaric ensemble are used to generate realistic biochar models taking into account experimentally determined H/C, O/C, N/C, aromaticity, micropore size range, micropore volumes and true densities of biochars. A pore generation approach was developed using virtual atoms, which is a Lennard-Jones sphere of varying van der Waals radius and softness. Its interaction via a soft-core potential with the biochar matrix allows the creation of pores with rough surfaces while varying the van der Waals radius parameters gives control to the pore-size distribution. We focused on microporosity, creating average pore sizes of 0.5 - 2 nm in diameter and pore volumes in the range of 0.05 – 1 cm3/g, which corresponds to experimental gas adsorption micropore sizes of amorphous porous biochars. Realistic biochar models with surface functionalities, micropore size distribution and pore morphologies were developed, and they could aid in the study of adsorption processes in confined micropores.Keywords: biochar, heteroatoms, micropore size, molecular dynamics simulations, surface functional groups, virtual atoms
Procedia PDF Downloads 719260 Airplane Stability during Climb/Descend Phase Using a Flight Dynamics Simulation
Authors: Niloufar Ghoreishi, Ali Nekouzadeh
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The stability of the flight during maneuvering and in response to probable perturbations is one of the most essential features of an aircraft that should be analyzed and designed for. In this study, we derived the non-linear governing equations of aircraft dynamics during the climb/descend phase and simulated a model aircraft. The corresponding force and moment dimensionless coefficients of the model and their variations with elevator angle and other relevant aerodynamic parameters were measured experimentally. The short-period mode and phugoid mode response were simulated by solving the governing equations numerically and then compared with the desired stability parameters for the particular level, category, and class of the aircraft model. To meet the target stability, a controller was designed and used. This resulted in significant improvement in the stability parameters of the flight.Keywords: flight stability, phugoid mode, short period mode, climb phase, damping coefficient
Procedia PDF Downloads 1749259 Modeling and Optimal Control of Hybrid Unmanned Aerial Vehicles with Wind Disturbance
Authors: Sunsoo Kim, Niladri Das, Raktim Bhattacharya
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This paper addresses modeling and control of a six-degree-of-freedom unmanned aerial vehicle capable of vertical take-off and landing in the presence of wind disturbances. We design a hybrid vehicle that combines the benefits of both the fixed-wing and the rotary-wing UAVs. A non-linear model for the hybrid vehicle is rapidly built, combining rigid body dynamics, aerodynamics of wing, and dynamics of the motor and propeller. Further, we design a H₂ optimal controller to make the UAV robust to wind disturbances. We compare its results against that of proportional-integral-derivative and linear-quadratic regulator based control. Our proposed controller results in better performance in terms of root mean squared errors and time responses during two scenarios: hover and level- flight.Keywords: hybrid UAVs, VTOL, aircraft modeling, H2 optimal control, wind disturbances
Procedia PDF Downloads 1589258 Nurses' Knowledge and Practice Regarding Care of Patients Connected to Intra-Aortic Balloon Pump at Cairo University Hospitals
Authors: Tharwat Ibrahim Rushdy, Warda Youssef Mohammed Morsy, Hanaa Ali Ahmed Elfeky
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Background: Intra-aortic balloon pump (IABP) is the first and the most commonly used mechanical circulatory support for patients with acute coronary syndromes and cardiogenic shock. Therefore, critical care nurses not only have to know how to monitor and operate the IABP, but also to provide interventions for preventing possible complications. Aim of the study: To assess nurses' knowledge and practices regarding care of patients connected to IABP at the ICUs of Cairo University Hospitals. Research design: A descriptive exploratory design was utilized. Sample: Convenience samples of 40 nurses were included in the current study. Setting: This study was carried out at the Intensive Care Units of Cairo University Hospitals. Tools of data collection: Three tools were developed, tested for clarity, and feasibility: a- Nurses' personal background sheet, b- IABP nurses' knowledge self-administered questionnaire, and c- IABP Nurses' practice observational checklist. Results: The majority of the studied sample had unsatisfactory knowledge and practice level (88% & 95%) respectively with a mean of 9.45+2.94 and 30.5+8.7, respectively. Unsatisfactory knowledge was found regarding description and physiological effects, nursing care, indications, contraindications, complications, weaning, and removal of IABP in percentage of 95%, 90%, 72.5%, and 57.5%, respectively, with a mean total knowledge score of 9.45 +2.94. In addition, unsatisfactory practice was found regarding about preparation and initiation of IABP therapy, nursing practice during therapy, weaning, and removal of IABP in percentages of (97.5%, 97.5%, and 90%), respectively. Finally, knowledge level was found to differ significantly in relation to gender (t = 2.46 at P ≤ 0.018). However, gender didn't play a role in relation to practice (t = 0.086 at P≤ 0.932). Conclusion: In spite of having vital role in assessment and management of critically ill patients, critical care nurses in the current study had in general unsatisfactory knowledge and practice regarding care of patients connected to IABP. Recommendation: updating knowledge and practice of ICU nurses through carrying out continuing educational programs about IABP; strict observation of nurses' practice when caring for patients connected to IABP and provision of guidance to correct of poor practices and replication of this study on larger probability sample selected from different geographical locations.Keywords: knowledge, practice, intra-aortic balloon pump (IABP), ICU nurses, intensive care unit (ICU), introduction
Procedia PDF Downloads 5039257 Mean-Field Type Modeling of Non-Local Congestion in Pedestrian Crowd Dynamics
Authors: Alexander Aurell
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One of the latest trends in the modeling of human crowds is the mean-field game approach. In the mean-field game approach, the motion of a human crowd is described by a nonstandard stochastic optimal control problem. It is nonstandard since congestion is considered, introduced through a dependence in the performance functional on the distribution of the crowd. This study extends the class of mean-field pedestrian crowd models to allow for non-local congestion and arbitrary, but finitely, many interacting crowds. The new congestion feature grants pedestrians a 'personal space' where crowding is undesirable. The model is treated as a mean-field type game which is derived from a particle picture. This, in contrast to a mean-field game, better describes a situation where the crowd can be controlled by a central planner. The latter is suitable for decentralized situations. Solutions to the mean-field type game are characterized via a Pontryagin-type Maximum Principle.Keywords: congestion, crowd dynamics, interacting populations, mean-field approximation, optimal control
Procedia PDF Downloads 4469256 Optimizing the Morphology and Flow Patterns of Scaffold Perfusion Systems for Effective Cell Deposition Using Computational Fluid Dynamics
Authors: Vineeth Siripuram, Abhineet Nigam
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A bioreactor is an engineered system that supports a biologically active environment. Along the years, the advancements in bioreactors have been widely accepted all over the world for varied applications ranging from sewage treatment to tissue cloning. Driven by tissue and organ shortage, tissue engineering has emerged as an alternative to transplantation for the reconstruction of lost or damaged organs. In this study, Computational fluid dynamics (CFD) has been used to model porous medium flow in scaffolds (taken from the literature) with different flow patterns. A detailed analysis of different scaffold geometries and their influence on cell deposition in the perfusion system is been carried out using Computational fluid dynamics (CFD). Considering the fact that, the scaffold should mimic the organs or tissues structures in a three-dimensional manner, certain assumptions were made accordingly. The research on scaffolds has been extensively carried out in different bioreactors. However, there has been less focus on the morphology of the scaffolds and the flow patterns in which the perfusion system is laid upon. The objective of this paper is to employ a computational approach using CFD simulation to determine the optimal morphology and the anisotropic measurements of the various samples of scaffolds. Using predictive computational modelling approach, variables which exert dominant effects on the cell deposition within the scaffold were prioritised and corresponding changes in morphology of scaffold and flow patterns in the perfusion systems are made. A Eulerian approach was carried on in multiple CFD simulations, and it is observed that the morphological and topological changes in the scaffold perfusion system are of great importance in the commercial applications of scaffolds.Keywords: cell seeding, CFD, flow patterns, modelling, perfusion systems, scaffold
Procedia PDF Downloads 1619255 Case Study on Exploration of Pediatric Cardiopulmonary Resuscitation among Involved Team Members in Pediatric Intensive Care Unit Institut Jantung Negara
Authors: Farah Syazwani Hilmy Zaki
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Background: Compared to adult cardiopulmonary resuscitation (CPR), high-quality research and evidence on pediatric CPR remain relatively scarce. This knowledge gap hinders the development of optimal guidelines and best practices for resuscitating children. Objectives: To explore pediatric intensive care unit (PICU) CPR current practices in PICU of Institut Jantung Negara (IJN) Malaysia. Method: The research employed a qualitative approach, utilising case study research design. The data collection process involved in-depth interviews and reviewing the Resuscitation Feedback Form. Purposive sampling was used to select two cases consisting of 14 participants. The study participants comprised a cardiologist, one anaesthetist, and twelve nurses. The data collected were transcribed and entered into NVivo software to facilitate theme development. Subsequently, thematic analysis was conducted to analyse the data. Findings: The study yielded key findings regarding the enhancement of PICU CPR practices. These findings are categorised into four themes, namely routine procedures, resuscitation techniques, team dynamics, and individual contributions. Establishment of cohesive team is crucial in facilitating the effectiveness of resuscitation. According to participants, lack of confidence, skills and knowledge presents significant obstacles to effective PICU CPR. Conclusion: The findings of this study indicate that the participants express satisfaction with the current practices of PICU CPR. However, the research also highlights the need for enhancements in various areas, including routine procedures, resuscitation techniques, as well as team and individual factors. Furthermore, it was suggested that additional training be conducted on the resuscitation process to enhance the preparedness of the medical team.Keywords: cardiopulmonary resuscitation, feedback, nurses, pediatric intensive care unit
Procedia PDF Downloads 959254 Spatio-Temporal Variation of Suspended Sediment Concentration in the near Shore Waters, Southern Karnataka, India
Authors: Ateeth Shetty, K. S. Jayappa, Ratheesh Ramakrishnan, A. S. Rajawat
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Suspended Sediment Concentration (SSC) was estimated for the period of four months (November, 2013 to February 2014) using Oceansat-2 (Ocean Colour Monitor) satellite images to understand the coastal dynamics and regional sediment transport, especially distribution and budgeting in coastal waters. The coastal zone undergoes continuous changes due to natural processes and anthropogenic activities. The importance of the coastal zone, with respect to safety, ecology, economy and recreation, demands a management strategy in which each of these aspects is taken into account. Monitoring and understanding the sediment dynamics and suspended sediment transport is an important issue for coastal engineering related activities. A study of the transport mechanism of suspended sediments in the near shore environment is essential not only to safeguard marine installations or navigational channels, but also for the coastal structure design, environmental protection and disaster reduction. Such studies also help in assessment of pollutants and other biological activities in the region. An accurate description of the sediment transport, caused by waves and tidal or wave-induced currents, is of great importance in predicting coastal morphological changes. Satellite-derived SSC data have been found to be useful for Indian coasts because of their high spatial (360 m), spectral and temporal resolutions. The present paper outlines the applications of state‐of‐the‐art operational Indian Remote Sensing satellite, Oceansat-2 to study the dynamics of sediment transport.Keywords: suspended sediment concentration, ocean colour monitor, sediment transport, case – II waters
Procedia PDF Downloads 2549253 Expansive-Restrictive Style: Conceptualizing Knowledge Workers
Authors: Ram Manohar Singh, Meenakshi Gupta
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Various terms such as ‘learning style’, ‘cognitive style’, ‘conceptual style’, ‘thinking style’, ‘intellectual style’ are used in literature to refer to an individual’s characteristic and consistent approach to organizing and processing information. However, style concepts are criticized for mutually overlapping definitions and confusing classification. This confusion should be addressed at the conceptual as well as empirical level. This paper is an attempt to bridge this gap in literature by proposing a new concept: expansive-restrictive intellectual style based on phenomenological analysis of an auto-ethnography and interview of 26 information technology (IT) professionals working in knowledge intensive organizations (KIOs) in India. Expansive style is an individual’s preference to expand his/her horizon of knowledge and understanding by gaining real meaning and structure of his/her work. On the contrary restrictive style is characterized by an individual’s preference to take minimalist approach at work reflected in executing a job efficiently without an attempt to understand the real meaning and structure of the work. The analysis suggests that expansive-restrictive style has three dimensions: (1) field dependence-independence (2) cognitive involvement and (3) epistemological beliefs.Keywords: expansive, knowledge workers, restrictive, style
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