Search results for: field change notice
13919 Etude 3D Quantum Numerical Simulation of Performance in the HEMT
Authors: A. Boursali, A. Guen-Bouazza
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We present a simulation of a HEMT (high electron mobility transistor) structure with and without a field plate. We extract the device characteristics through the analysis of DC, AC and high frequency regimes, as shown in this paper. This work demonstrates the optimal device with a gate length of 15 nm, InAlN/GaN heterostructure and field plate structure, making it superior to modern HEMTs when compared with otherwise equivalent devices. This improves the ability to bear the burden of the current density passes in the channel. We have demonstrated an excellent current density, as high as 2.05 A/m, a peak extrinsic transconductance of 0.59S/m at VDS=2 V, and cutting frequency cutoffs of 638 GHz in the first HEMT and 463 GHz for Field plate HEMT., maximum frequency of 1.7 THz, maximum efficiency of 73%, maximum breakdown voltage of 400 V, leakage current density IFuite=1 x 10-26 A, DIBL=33.52 mV/V and an ON/OFF current density ratio higher than 1 x 1010. These values were determined through the simulation by deriving genetic and Monte Carlo algorithms that optimize the design and the future of this technology.Keywords: HEMT, silvaco, field plate, genetic algorithm, quantum
Procedia PDF Downloads 34913918 Impact of Climate Shifting-Change on Rural People and Agricultural Life
Authors: Arshad A. Narejo, M. Javed Sheikh, G. Mujtaba Khushk, Naeem A Qureshi, M. Ali Sheikh
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Climate change not only influences on agriculture activities but also has certain effects on daily human activities, as well as on overall human health. Keeping in view the significance and huge research gap on the issues, the researchers have found an opportunity to conduct a study in Sindh province of Pakistan, in which the issue of climate shifting/change regarding temperature and precipitation were discussed with the local farmers of district Hyderabad. The quantified perception was gathered on a reliable and valid scale from 200 respondents and was analyzed through SPSS and AMOS software. The result of this study revealed that the significant changes are being occurred in summer (r²=0.96; M=6.78) and winter seasons (r²=0.71; M=6.57), therefore it is leaving bad effects on human health (r²=0.96) and behavior of the local population (r²=0.70). In addition, the change in the cropping calendar, i.e., timing of sowing (r²=0.69; M=8.42) and harvesting (r²=0.79; M=8.27) of different crops have been altered due to changes in local weather patterns. Since the local farmers are also facing seed germination (r²=0.57; M=7.98) problems, it is therefore recommended that concerned authorities/departments should revise the agricultural calendar. Besides this, respondents were in opinion that actual summer starts even before the vacation and cold season starts when winter vacations ended. Thus, the government and other concerned departments should reconsider or reschedule the vacation regulation policy (r²=0.70) at least at the provincial level.Keywords: climate, climate shifting/change, impact on daily life, impact on agricultural activities
Procedia PDF Downloads 13113917 Climatic Roots of Piracy in Red Sea
Authors: Nasser Karami
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Piracy in the North West of Indian Ocean and the Red Sea has become a global crisis in recent years. Pirates of this area are often very poor people from the Horn of Africa and the western coast of the Red Sea. Climatic and geographical evidence suggests that poverty and destruction of social structures in the region have directly relation to prolonged-drought. Indeed, after the seventies (more than 40 years ago) due to the long-term drought in the region, all political, economic and social structures had declined. Spread of terrorism, violent extremism and of course piracy, are main effects of climate change and drought of this regression. It is disturbing to say the climatic documents say that because of global climate change, severe drought will continue in this region. This mean that the dangers worse than piracy threatens the future of this area. Forty-year data that has assessed in this study indicate that there is direct relationship between spread of drought and piracy in the Red Sea.Keywords: climate, poverty, climate change, drought, piracy in red sea
Procedia PDF Downloads 49813916 Use of Data of the Remote Sensing for Spatiotemporal Analysis Land Use Changes in the Eastern Aurès (Algeria)
Authors: A. Bouzekri, H. Benmassaud
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Aurès region is one of the arid and semi-arid areas that have suffered climate crises and overexploitation of natural resources they have led to significant land degradation. The use of remote sensing data allowed us to analyze the land and its spatiotemporal changes in the Aurès between 1987 and 2013, for this work, we adopted a method of analysis based on the exploitation of the images satellite Landsat TM 1987 and Landsat OLI 2013, from the supervised classification likelihood coupled with field surveys of the mission of May and September of 2013. Using ENVI EX software by the superposition of the ground cover maps from 1987 and 2013, one can extract a spatial map change of different land cover units. The results show that between 1987 and 2013 vegetation has suffered negative changes are the significant degradation of forests and steppe rangelands, and sandy soils and bare land recorded a considerable increase. The spatial change map land cover units between 1987 and 2013 allows us to understand the extensive or regressive orientation of vegetation and soil, this map shows that dense forests give his place to clear forests and steppe vegetation develops from a degraded forest vegetation and bare, sandy soils earn big steppe surfaces that explain its remarkable extension. The analysis of remote sensing data highlights the profound changes in our environment over time and quantitative monitoring of the risk of desertification.Keywords: remote sensing, spatiotemporal, land use, Aurès
Procedia PDF Downloads 33513915 Integration of Magnetoresistance Sensor in Microfluidic Chip for Magnetic Particles Detection
Authors: Chao-Ming Su, Pei-Sheng Wu, Yu-Chi Kuo, Yin-Chou Huang, Tan-Yueh Chen, Jefunnie Matahum, Tzong-Rong Ger
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Application of magnetic particles (MPs) has been applied in biomedical field for many years. There are lots of advantages through this mediator including high biocompatibility and multi-diversified bio-applications. However, current techniques for evaluating the quantity of the magnetic-labeled sample assays are rare. In this paper, a Wheatstone bridge giant magnetoresistance (GMR) sensor integrated with a homemade detecting system was fabricated and used to quantify the concentration of MPs. The homemade detecting system has shown high detecting sensitivity of 10 μg/μl of MPs with optimized parameter vertical magnetic field 100 G, horizontal magnetic field 2 G and flow rate 0.4 ml/min.Keywords: magnetic particles, magnetoresistive sensors, microfluidics, biosensor
Procedia PDF Downloads 39913914 Sustainable Urban Resilience and Climate-Proof Urban Planning
Authors: Carmela Mariano
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The literature, the scientific and disciplinary debate related to the impacts of climate change on the territory has highlighted, in recent years, the need for climate-proof and resilient tools of urban planning that adopt an integrated and inter-scalar approach for the construction of urban regeneration strategies by the objectives of the European Strategy on adaptation to climate change, the 2030 Agenda for Sustainable Development and the Climate Conference. This article addresses the operational implications of urban climate resilience in urban planning tools as a priority objective of policymakers (government bodies, institutions, etc.) to respond to the risks of climate change-related impacts on the environment. Within the general framework of the research activities carried out by the author, this article provides a critical synthesis of the analysis and evaluation of some case studies from the Italian national context, which enabled, through an inductive method, the assessment of the process of implementing the adaptation to climate change within the regional urban planning frameworks (regional urban laws), specific regional adaptation strategies or local adaptation plans and within the territorial and urban planning tools of a metropolitan or local scale. This study aims to identify theoretical–methodological, and operational references for the innovation and integration of planning tools concerning climate change that allow local planners to test these references in specific territorial contexts to practical adaptation strategies for local action.Keywords: urban resilience, urban regeneration, climate-proof-planning, urban planning
Procedia PDF Downloads 1713913 Curating Pluralistic Futures: Leveling up for Whole-Systems Change
Authors: Daniel Schimmelpfennig
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This paper attempts to delineate the idea to curate the leveling up for whole-systems change. Curation is the act fo select, organize, look after, or present information from a professional point of view through expert knowledge. The trans-paradigmatic, trans-contextual, trans-disciplinary, trans-perspective of trans-media futures studies hopes to enable a move from a monochrome intellectual pursuit towards breathing a higher dimensionality. Progressing to the next level to equip actors for whole-systems change is in consideration of the commonly known symptoms of our time as well as in anticipation of future challenges, both a necessity and desirability. Systems of collective intelligence could potentially scale regenerative, adaptive, and anticipatory capacities. How could such a curation then be enacted and implemented, to initiate the process of leveling-up? The suggestion here is to focus on the metasystem transition, the bio-digital fusion, namely, by merging neurosciences, the ontological design of money as our operating system, and our understanding of the billions of years of time-proven permutations in nature, biomimicry, and biological metaphors like symbiogenesis. Evolutionary cybernetics accompanies the process of whole-systems change.Keywords: bio-digital fusion, evolutionary cybernetics, metasystem transition, symbiogenesis, transmedia futures studies
Procedia PDF Downloads 15513912 Study on the Impact of Size and Position of the Shear Field in Determining the Shear Modulus of Glulam Beam Using Photogrammetry Approach
Authors: Niaz Gharavi, Hexin Zhang
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The shear modulus of a timber beam can be determined using torsion test or shear field test method. The shear field test method is based on shear distortion measurement of the beam at the zone with the constant transverse load in the standardized four-point bending test. The current code of practice advises using two metallic arms act as an instrument to measure the diagonal displacement of the constructing square. The size and the position of the constructing square might influence the shear modulus determination. This study aimed to investigate the size and the position effect of the square in the shear field test method. A binocular stereo vision system has been employed to determine the 3D displacement of a grid of target points. Six glue laminated beams were produced and tested. Analysis of Variance (ANOVA) was performed on the acquired data to evaluate the significance of the size effect and the position effect of the square. The results have shown that the size of the square has a noticeable influence on the value of shear modulus, while, the position of the square within the area with the constant shear force does not affect the measured mean shear modulus.Keywords: shear field test method, structural-sized test, shear modulus of Glulam beam, photogrammetry approach
Procedia PDF Downloads 29113911 Evolution and Merging of Double-Diffusive Layers in a Vertically Stable Compositional Field
Authors: Ila Thakur, Atul Srivastava, Shyamprasad Karagadde
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The phenomenon of double-diffusive convection is driven by density gradients created by two different components (e.g., temperature and concentration) having different molecular diffusivities. The evolution of horizontal double-diffusive layers (DDLs) is one of the outcomes of double-diffusive convection occurring in a laterally/vertically cooled rectangular cavity having a pre-existing vertically stable composition field. The present work mainly focuses on different characteristics of the formation and merging of double-diffusive layers by imposing lateral/vertical thermal gradients in a vertically stable compositional field. A CFD-based twodimensional fluent model has been developed for the investigation of the aforesaid phenomena. The configuration containing vertical thermal gradients shows the evolution and merging of DDLs, where, elements from the same horizontal plane move vertically and mix with surroundings, creating a horizontal layer. In the configuration of lateral thermal gradients, a specially oriented convective roll was found inside each DDL and each roll was driven by the competing density change due to the already existing composition field and imposed thermal field. When the thermal boundary layer near the vertical wall penetrates the salinity interface, it can disrupt the compositional interface and can lead to layer merging. Different analytical scales were quantified and compared for both configurations. Various combinations of solutal and thermal Rayleigh numbers were investigated to get three different regimes, namely; stagnant regime, layered regime and unicellular regime. For a particular solutal Rayleigh number, a layered structure can originate only for a range of thermal Rayleigh numbers. Lower thermal Rayleigh numbers correspond to a diffusion-dominated stagnant regime. Very high thermal Rayleigh corresponds to a unicellular regime with high convective mixing. Different plots identifying these three regimes, number, thickness and time of existence of DDLs have been studied and plotted. For a given solutal Rayleigh number, an increase in thermal Rayleigh number increases the width but decreases both the number and time of existence of DDLs in the fluid domain. Sudden peaks in the velocity and heat transfer coefficient have also been observed and discussed at the time of merging. The present study is expected to be useful in correlating the double-diffusive convection in many large-scale applications including oceanography, metallurgy, geology, etc. The model has also been developed for three-dimensional geometry, but the results were quite similar to that of 2-D simulations.Keywords: double diffusive layers, natural convection, Rayleigh number, thermal gradients, compositional gradients
Procedia PDF Downloads 8413910 3D Quantum Simulation of a HEMT Device Performance
Authors: Z. Kourdi, B. Bouazza, M. Khaouani, A. Guen-Bouazza, Z. Djennati, A. Boursali
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We present a simulation of a HEMT (high electron mobility transistor) structure with and without a field plate. We extract the device characteristics through the analysis of DC, AC and high frequency regimes, as shown in this paper. This work demonstrates the optimal device with a gate length of 15 nm, InAlN/GaN heterostructure and field plate structure, making it superior to modern HEMTs when compared with otherwise equivalent devices. This improves the ability to bear the burden of the current density passes in the channel. We have demonstrated an excellent current density, as high as 2.05 A/mm, a peak extrinsic transconductance of 590 mS/mm at VDS=2 V, and cutting frequency cutoffs of 638 GHz in the first HEMT and 463 GHz for Field plate HEMT., maximum frequency of 1.7 THz, maximum efficiency of 73%, maximum breakdown voltage of 400 V, DIBL=33.52 mV/V and an ON/OFF current density ratio higher than 1 x 1010. These values were determined through the simulation by deriving genetic and Monte Carlo algorithms that optimize the design and the future of this technology.Keywords: HEMT, Silvaco, field plate, genetic algorithm, quantum
Procedia PDF Downloads 47613909 State of Play for the World’s Largest Greenhouse Gas Emitters
Authors: Olivia Meeschaert
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The Conference of the Parties (COP) refers to the countries that signed on to the United Nations Framework Convention on Climate Change. This annual conference provides a platform for countries to voice their major climate concerns, negotiate on a number of global issues, and come to agreements with the world’s largest emitters on how to make incremental changes that will achieve global climate goals. Historically, the outcome of COP includes major climate pledges and international agreements. COP27 will take place in Egypt at the beginning of November 2022. The 197 parties will come together to develop solutions to the dire consequences of climate change that many people around the world are already experiencing. The war in Ukraine will require a different tone from last year’s COP, particularly given that major impacts of the war are being felt throughout Europe and have had a detrimental effect on the region’s progress in achieving the benchmarks set in their climate pledges. Last year’s COP opened with many climate advocates feeling optimistic but the commitments made in Glasgow have so far remained empty promises, and the main contributors to climate change – China, the European Union, and the United States of America – have not moved fast enough.Keywords: environment, law and policy, climate change, greenhouse gas, conference of the parties, China, United States, European Union
Procedia PDF Downloads 7913908 Finite Element Method for Calculating Temperature Field of Main Cable of Suspension Bridge
Authors: Heng Han, Zhilei Liang, Xiangong Zhou
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In this paper, the finite element method is used to study the temperature field of the main cable of the suspension bridge, and the calculation method of the average temperature of the cross-section of the main cable suitable for the construction control of the cable system is proposed; By comparing and analyzing the temperature field of the main cable with five diameters, a reasonable diameter limit for calculating the average temperature of the cross section of the main cable by finite element method is proposed. The results show that the maximum error of this method is less than 1℃, which meets the requirements of construction control accuracy; For the main cable with a diameter greater than 400mm, the surface temperature measuring points combined with the finite element method shall be used to calculate the average cross-section temperature.Keywords: suspension bridge, main cable, temperature field, finite element
Procedia PDF Downloads 16013907 Crossing Multi-Source Climate Data to Estimate the Effects of Climate Change on Evapotranspiration Data: Application to the French Central Region
Authors: Bensaid A., Mostephaoui T., Nedjai R.
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Climatic factors are the subject of considerable research, both methodologically and instrumentally. Under the effect of climate change, the approach to climate parameters with precision remains one of the main objectives of the scientific community. This is from the perspective of assessing climate change and its repercussions on humans and the environment. However, many regions of the world suffer from a severe lack of reliable instruments that can make up for this deficit. Alternatively, the use of empirical methods becomes the only way to assess certain parameters that can act as climate indicators. Several scientific methods are used for the evaluation of evapotranspiration which leads to its evaluation either directly at the level of the climatic stations or by empirical methods. All these methods make a point approach and, in no case, allow the spatial variation of this parameter. We, therefore, propose in this paper the use of three sources of information (network of weather stations of Meteo France, World Databases, and Moodis satellite images) to evaluate spatial evapotranspiration (ETP) using the Turc method. This first step will reflect the degree of relevance of the indirect (satellite) methods and their generalization to sites without stations. The spatial variation representation of this parameter using the geographical information system (GIS) accounts for the heterogeneity of the behaviour of this parameter. This heterogeneity is due to the influence of site morphological factors and will make it possible to appreciate the role of certain topographic and hydrological parameters. A phase of predicting the evolution over the medium and long term of evapotranspiration under the effect of climate change by the application of the Intergovernmental Panel on Climate Change (IPCC) scenarios gives a realistic overview as to the contribution of aquatic systems to the scale of the region.Keywords: climate change, ETP, MODIS, GIEC scenarios
Procedia PDF Downloads 10013906 Validating Thermal Performance of Existing Wall Assemblies Using In-Situ Measurements
Authors: Shibei Huang
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In deep energy retrofits, the thermal performance of existing building envelopes is often difficult to determine with a high level of accuracy. For older buildings, the records of existing assemblies are often incomplete or inaccurate. To obtain greater baseline performance accuracy for energy models, in-field measurement tools can be used to obtain data on the thermal performance of the existing assemblies. For a known assembly, these field measurements assist in validating the U-factor estimates. If the field-measured U-factor consistently varies from the calculated prediction, those measurements prompt further study. For an unknown assembly, successful field measurements can provide approximate U-factor evaluation, validate assumptions, or identify anomalies requiring further investigation. Using case studies, this presentation will focus on the non-destructive methods utilizing a set of various field tools to validate the baseline U-factors for a range of existing buildings with various wall assemblies. The lessons learned cover what can be achieved, the limitations of these approaches and tools, and ideas for improving the validity of measurements. Key factors include the weather conditions, the interior conditions, the thermal mass of the measured assemblies, and the thermal profiles of the assemblies in question.Keywords: existing building, sensor, thermal analysis, retrofit
Procedia PDF Downloads 6313905 Improving the Employee Transfer Experience within an Organization
Authors: Drew Fockler
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This research examines how to improve an employee’s experience when transferring between departments within an organization. This research includes a historical review of a Canadian retail organization. Based on this historical review, gaps are identified between current and future visions to show where problems with existing training and development practices need to be resolved to reduce front-line employee turnover within an organization. The strategies within this paper support leaders through the LEAD: Listen, Explore, Act and Develop, Change Management Model. The LEAD Change Management Model supports the change process. This research proposes three possible solutions to improve an employee who is transferring between departments. The best solution to resolve the problem of improving an employee moving between departments experience is creating a Training Manager position within the retail store. A Training Manager position could support both employees and leadership with training and development of staff who are moving between departments. Within this research, an implementation plan using the TransX Model was created. The TransX Model is a hybrid of Leader-Member Exchange Theory and Transformational Leadership Theory to facilitate this organizational change within an organization by creating a common vision. Finally, this research provides the next steps as well as future considerations to enhance the training manager role within an organization.Keywords: employee transfers, employee engagement, human resources, employee induction, TransX model, lead change management model
Procedia PDF Downloads 7713904 Onmanee Prajuabjinda, Pakakrong Thondeeying, Jipisute Chunthorng-Orn, Bhanuz Dechayont, Arunporn Itharat
Authors: Ekrem Erdem, Can Tansel Tugcu
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Improved resource efficiency of production is a key requirement for sustainable growth, worldwide. In this regards, by considering the energy and tourism as the extra inputs to the classical Coub-Douglas production function, this study aims at investigating the efficiency changes in the North African countries. To this end, the study uses panel data for the period 1995-2010 and adopts the Malmquist index based on the data envelopment analysis. Results show that tourism increases technical and scale efficiencies, while it decreases technological and total factor productivity changes. On the other hand, when the production function is augmented by the energy input, technical efficiency change decreases, while the technological change, scale efficiency change and total factor productivity change increase. Thus, in order to satisfy the needs for sustainable growth, North African governments should take some measures for increasing the contribution that the tourism makes to economic growth and some others for efficient use of resources in the energy sector.Keywords: data envelopment analysis, economic efficiency, North African countries, sustainable growth
Procedia PDF Downloads 34313903 Disaster Adaptation Mechanism and Disaster Prevention Adaptation Planning Strategies for Industrial Parks in Response to Climate Change and Different Socio-Economic Disasters
Authors: Jen-Te Pai, Jao-Heng Liu, Shin-En Pai
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The impact of climate change has intensified in recent years, causing Taiwan to face higher frequency and serious natural disasters. Therefore, it is imperative for industrial parks manufacturers to promote adaptation policies in response to climate change. On the other hand, with the rise of the international anti-terrorism situation, once a terrorist attack occurs, it will attract domestic and international media attention, especially the strategic and economic status of the science park. Thus, it is necessary to formulate adaptation and mitigation strategies under climate change and social economic disasters. After reviewed the literature about climate change, urban disaster prevention, vulnerability assessment, and risk communication, the study selected 62 industrial parks compiled by the Industrial Bureau of the Ministry of Economic Affairs of Taiwan as the research object. This study explored the vulnerability and disaster prevention and disaster relief functional assessment of these industrial parks facing of natural and socio-economic disasters. Furthermore, this study explored planned adaptation of industrial parks management section and autonomous adaptation of corporate institutions in the park. The conclusion of this study is that Taiwan industrial parks with a higher vulnerability to natural and socio-economic disasters should employ positive adaptive behaviours.Keywords: adaptive behaviours, analytic network process, vulnerability, industrial parks
Procedia PDF Downloads 14513902 Effect of Climate Change on Nutritional Status of Women in Nigeria
Authors: Onu Theresa Chinyere
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The study evaluates the perceived effect of climate change on nutritional status of women in Nigeria. Five research questions and two hypotheses were formulated to guide the study. The study adopted a survey and experimental study research design. One thousand two hundred and fifty one (1,250) respondents were selected from different State in Nigeria using multistage sampling technique. The instruments used to collect data were questionnaire and personal interview on socio economic characteristics of respondents, while Anthropometric data (height and weight) were also used. The data was analyzed using t-test statistic, decided at 50% level of significance. The study found that most states in Nigeria experience high winds, warmer and frequent hot days and night over most land areas, droughts and tides during climate change events. The respondent unanimously agree that climate change causes reduction in food yields, decline in food availability/supply, negatively affecting soil quality, carbon fertilization, decreases flexibilities in technology choices to strengthen food production. The Anthropometric analysis shows that out of 1250 women sampled, 560 (44.8%) maintain normal weight, while 405 (32.40%) women were found to be underweight, since their body mass index is less that 18.5. There were few cases of obesity among the surveyed women since only 80 out of 1250 which represent 6.4% of the women were obese. Bases on the findings, the following recommendations were made-local fertilizer should be encouraged to boost foods yield especially during climate change: women should imbibe the culture of preservation or reservoir that will help in mitigating the effects of climate on food intake and nutritional status, especially during the crisis period, among others.Keywords: climate change, nutrition anthropometric analysis, obesity culture, environment and women among others
Procedia PDF Downloads 42513901 Mobile Application Interventions in Positive Psychology: Current Status and Recommendations for Effective App Design
Authors: Gus Salazar, Jeremy Bekker, Lauren Linford, Jared Warren
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Positive psychology practices allow for its principles to be applied to all people, regardless of their current level of functioning. To increase the dissemination of these practices, interventions are being adapted for use with digital technology, such as mobile apps. However, the research regarding positive psychology mobile app interventions is still in its infancy. In an effort to facilitate progress in this important area, we 1) conducted a qualitative review to summarize the current state of the positive psychology mobile app literature and 2) developed research-supported recommendations for positive psychology app development to maximize behavior change. In our literature review, we found that while positive psychology apps varied widely in content and purpose, there was a near-complete lack of research supporting their effectiveness. Most apps provided no rationale for the behavioral change techniques (BCTs) they employed in their app, and most did not develop their app with specific theoretical frameworks or design models in mind. Given this problem, we recommended four steps for effective positive psychology app design. First, developers must establish their app in a research-supported theory of change. Second, researchers must select appropriate behavioral change techniques which are consistent with their app’s goals. Third, researchers must leverage effective design principles. These steps will help mobile applications use data-driven methods for encouraging behavior change in their users. Lastly, we discuss directions for future research. In particular, researchers must investigate the effectiveness of various BCTs in positive psychology interventions. Although there is some research on this point, we do not yet clearly understand the mechanisms within the apps that lead to behavior change. Additionally, app developers must also provide data on the effectiveness of their mobile apps. As developers follow these steps for effective app development and as researchers continue to investigate what makes these apps most effective, we will provide millions of people in need with access to research-based mental health resources.Keywords: behavioral change techniques, mobile app, mobile intervention, positive psychology
Procedia PDF Downloads 22413900 Numerical Analysis of Supersonic Impinging Jets onto Resonance Tube
Authors: Shinji Sato, M. M. A. Alam, Manabu Takao
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In recent, investigation of an unsteady flow inside the resonance tube have become a strongly motivated research field for their potential application as high-frequency actuators. By generating a shock wave inside the resonance tube, a high temperature and pressure can be achieved inside the tube, and this high temperature can also be used to ignite a jet engine. In the present research, a computational fluid dynamics (CFD) analysis was carried out to investigate the flow inside the resonance tube. The density-based solver of rhoCentralFoam in OpenFOAM was used to numerically simulate the flow. The supersonic jet that was driven by a cylindrical nozzle with a nominal exit diameter of φd = 20.3 mm impinged onto the resonance tube. The jet pressure ratio was varied between 2.6 and 7.8. The gap s between the nozzle exit and tube entrance was changed between 1.5d and 3.0d. The diameter and length of the tube were taken as D = 1.25d and L=3.0D, respectively. As a result, when a supersonic jet has impinged onto the resonance tube, a compression wave was found generating inside the tube and propagating towards the tube end wall. This wave train resulted in a rise in the end wall gas temperature and pressure. While, in an outflow phase, the gas near tube enwall was found cooling back isentropically to its initial temperature. Thus, the compression waves repeated a reciprocating motion in the tube like a piston, and a fluctuation in the end wall pressures and temperatures were observed. A significant change was found in the end wall pressures and temperatures with a change of jet flow conditions. In this study, the highest temperature was confirmed at a jet pressure ratio of 4.2 and a gap of s=2.0dKeywords: compressible flow, OpenFOAM, oscillations, a resonance tube, shockwave
Procedia PDF Downloads 14913899 The Consequences of Regime Change in Iraq; Formation and Continuation of Geopolitical Crises
Authors: Ali Asghar Sotoudeh
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Since the US invasion of Iraq in 2003 and the subsequent regime change, internal conflicts between political and ethnic-religious groups have become a hallmark of Iraqi political dynamism. The most important manifestations of these conflicts are the Kurdish-central government conflicts, as well as fundamentalism since 2003. As a result, it seems not only US presence in Iraq under the pretext of fighting terrorism and expanding democracy has not had a positive effect on controlling fundamentalism and political stability in Iraq, but it has paved the way for the formation and continuation of geopolitical crises in the form of disputes over territory and sources of power. In this regard, given the importance of the study, the main purpose of this study is to examine the process of the impact of US regime-change policy on the formation and continuation of geopolitical crises in Iraq. The central question of this study is, what effect has the US regime change policy had on Iraq's domestic political processes? Findings show that regime change and subsequent imposed federalism have widened the gaps in Iraq's sectarian-ethnic system. As a result, the geopolitical crisis in the context of the dispute over geographical territory and sources of power between ethnic-religious groups has become the most important political dynamic in Iraq since the occupation. The research method in this article is descriptive-analytical, and the data collection method is library and internet resources.Keywords: Iraq, united states, geopolitical crisis, ethno-religious conflict, political federalism
Procedia PDF Downloads 14713898 Population Change and Migration in Istanbul Metropolitan Area: Tarlabaşı Case
Authors: Gulsen Yilmaz
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Istanbul’s population has jumped by over 1 million in the past four years, to a level surpassing the overall population of 64 provinces in the country, according to data from the Turkish Statistical Institute (TÜİK). In this paper, Istanbul's population change and migration effects can be examined in detail Tarlabasi neighborhood cultural center of the city of Istanbul, Istiklal Street, which is located a few hundred meters away. Tarlabasi the end of the nineteenth century in the historic district with built in the early twentieth century, there are four or five storey historic buildings. Tarlabasi, here come from southeastern Turkey and the illegal African immigrants living in Roma origin by the Kurds as a residential area is used. In this area to improve the quality of life for urban renewal projects have been initiated. The aim of this paper is to explore the spatial effects of demographic change and migration with Tarlabasi example.Keywords: migration, immigration, Tarlabaşı, urban transformation
Procedia PDF Downloads 51113897 The Publication Impact of London’s Air Ambulance on the Field of Pre-Hospital Medicine and Its Application to Air Ambulances Internationally: A Bibliometric Analysis
Authors: Maria Ahmad, Alexandra Valetopoulou, Michael D. Christian
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Background: London’s Air Ambulance (LAA) provides advanced pre-hospital trauma care across London, bringing specialist resources and expert trauma teams to patients. Since its inception 32 years ago, LAA has treated over 40,000 pre-hospital patients and significantly contributed to pre-hospital patient care in London. To the authors’ best knowledge, this is the first analysis to quantify the magnitude of the publication impact of LAA on the international field of pre-hospital medicine. Method: We searched the Scopus, Web of Science, Google Scholar and PubMed databases to identify LAA focused articles. These were defined as articles on the topic of pre-hospital medicine which either utilised data from LAA, or focused on LAA patients, or were authored by LAA clinicians. A bibliometric analysis was conducted and the impact of each eligible article was classified as either: high (article directly influenced the change or creation of clinical guidelines); medium (the article was referenced in clinical guidelines or had >20 Google Scholar citations or >10 PubMed citations); or low impact (article had <20 Google Scholar citations or <10 PubMed citations). Results: The literature search yielded 1,120 articles in total. 198 articles met our inclusion criteria, and their full text was analysed to determine the level of impact. 19 articles were classified as high-impact, 76 as medium-impact, and 103 as low-impact. 20 of the 76 medium-impact articles were referenced in clinical guidelines but had not prompted changes to the guidelines. Conclusion: To our knowledge, this review is the first to quantify the significant publication impact of LAA within the field of pre-hospital medicine over the last 32 years. LAA publications have focused on and driven clinical innovations in trauma care, particularly in pre-hospital anaesthesia, haemorrhage control, and major incidents, with many impacting national and international guidelines. We recommend a greater emphasis on multidisciplinary pre-hospital collaboration in publications in future research and quality improvement projects across all pre-hospital services.Keywords: air ambulance, pre-hospital medicine, London’s Air Ambulance, London HEMS
Procedia PDF Downloads 7613896 Challenges, Chances and Possibilities during the Change Management Process of the National Defence Academy Vienna
Authors: Georg Ebner
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The National Defence Academy, an element of the Austrian Ministry of Defence, is undergoing a transition process leading the Academy towards a new target structure that is currently being developed. In so doing, in addition to a subject-oriented approach, also an employee-oriented process was introduced. This process was initiated by the Ministry of Defence and should lead the National Defence Academy into a new constellation. During this process, the National Defence Academy worked in very special adapted World Café sessions. The “change manager” dealed with very different issues. They took the data feedback from the sessions and prepared with the feedback and information from the guidance the next session. So they got various information and a very different picture around the academy. It was very helpful to involve most of the employees of the academy during this process and to take their knowledge and wisdom. The process himself started with very different feelings and ended with great consent. A very interesting part of this process was also that the commander and his deputy worked together during all of this sessions and they answered all questions from the employees in time. The adapted World Café phases were necessary to deal with the information of the staff and to implement these absolutely needful data into this process. In cooperation with the responsible Headquarters, the first items resulting from the World Café phases could already be fed back to the employees and be implemented. The staff-oriented process is currently supported via a point of contact, through which the staff can contribute ideas as well, but also by the active information policy on the part of the Headquarters. The described change process makes innovative innovations possible. So far, in the event of change processes staff members have been entrusted only with the concrete implementation plan and tied into the process when the respective workplaces were to be re-staffed. The procedure described here can be seen as food-for-thought for further change processes. The findings of this process are that a staff oriented process can lead an organisation into a new era of thinking and working. This process has shown, that a lot of innovative ideas can also take place in a ministry. This process can be a background for a lot of change management processes in ministries and governmental and non-governmental organisations.Keywords: both directions approach, change management, knowledge database, transformation process, World Cafe
Procedia PDF Downloads 19213895 Privacy Label: An Alternative Approach to Present Privacy Policies from Online Services to the User
Authors: Diego Roberto Goncalves De Pontes, Sergio Donizetti Zorzo
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Studies show that most users do not read privacy policies from the online services they use. Some authors claim that one of the main causes of this is that policies are long and usually hard to understand, which make users lose interest in reading them. In this scenario, users may agree with terms without knowing what kind of data is being collected and why. Given that, we aimed to develop a model that would present the privacy policies contents in an easy and graphical way for the user to understand. We call it the Privacy Label. Using information recovery techniques, we propose an architecture that is able to extract information about what kind of data is being collected and to what end in the policies and show it to the user in an automated way. To assess our model, we calculated the precision, recall and f-measure metrics on the information extracted by our technique. The results for each metric were 68.53%, 85.61% e 76,13%, respectively, making it possible for the final user to understand which data was being collected without reading the whole policy. Also, our proposal can facilitate the notice-and-choice by presenting privacy policy information in an alternative way for online users.Keywords: privacy, policies, user behavior, computer human interaction
Procedia PDF Downloads 30713894 Analyzing the Climate Change Impact and Farmer's Adaptability Strategies in Khyber Pakhtunkhwa, Pakistan
Authors: Khuram Nawaz Sadozai, Sonia
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The agriculture sector is deemed more vulnerable to climate change as its variation can directly affect the crop’s productivity, but farmers’ adaptation strategies play a vital role in climate change-agriculture relationship. Therefore, this research has been undertaken to assess the Climate Change impact on wheat productivity and farmers’ adaptability strategies in Khyber Pakhtunkhwa province, Pakistan. The panel dataset was analyzed to gauge the impact of changing climate variables (i.e., temperature, rainfall, and humidity) on wheat productivity from 1985 to 2015. Amid the study period, the fixed effect estimates confirmed an inverse relationship of temperature and rainfall on the wheat yield. The impact of temperature is observed to be detrimental as compared to the rainfall, causing 0.07 units reduction in the production of wheat with 1C upsurge in temperature. On the flip side, humidity revealed a positive association with the wheat productivity by confirming that high humidity could be beneficial to the production of the crop over time. Thus, this study ensures significant nexus between agricultural production and climatic parameters. However, the farming community in the underlying study area has limited knowledge about the adaptation strategies to lessen the detrimental impact of changing climate on crop yield. It is recommended that farmers should be well equipped with training and advanced agricultural management practices under the realm of climate change. Moreover, innovative technologies pertinent to the agriculture system should be encouraged to handle the challenges arising due to variations in climate factors.Keywords: climate change, fixed effect model, panel data, wheat productivity
Procedia PDF Downloads 12313893 A Study on Analysis of Magnetic Field in Induction Generator for Small Francis Turbine Generator
Authors: Young-Kwan Choi, Han-Sang Jeong, Yeon-Ho Ok, Jae-Ho Choi
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The purpose of this study is to verify validity of design by testing output of induction generator through finite element analysis before manufacture of induction generator designed. Characteristics in the operating domain of induction generator can be understood through analysis of magnetic field according to load (rotational speed) of induction generator. Characteristics of induction generator such as induced voltage, current, torque, magnetic flux density (magnetic flux saturation), and loss can be predicted by analysis of magnetic field.Keywords: electromagnetic analysis, induction generator, small hydro power generator, small francis turbine generator
Procedia PDF Downloads 147513892 High Speed Motion Tracking with Magnetometer in Nonuniform Magnetic Field
Authors: Jeronimo Cox, Tomonari Furukawa
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Magnetometers have become more popular in inertial measurement units (IMU) for their ability to correct estimations using the earth's magnetic field. Accelerometer and gyroscope-based packages fail with dead-reckoning errors accumulated over time. Localization in robotic applications with magnetometer-inclusive IMUs has become popular as a way to track the odometry of slower-speed robots. With high-speed motions, the accumulated error increases over smaller periods of time, making them difficult to track with IMU. Tracking a high-speed motion is especially difficult with limited observability. Visual obstruction of motion leaves motion-tracking cameras unusable. When motions are too dynamic for estimation techniques reliant on the observability of the gravity vector, the use of magnetometers is further justified. As available magnetometer calibration methods are limited with the assumption that background magnetic fields are uniform, estimation in nonuniform magnetic fields is problematic. Hard iron distortion is a distortion of the magnetic field by other objects that produce magnetic fields. This kind of distortion is often observed as the offset from the origin of the center of data points when a magnetometer is rotated. The magnitude of hard iron distortion is dependent on proximity to distortion sources. Soft iron distortion is more related to the scaling of the axes of magnetometer sensors. Hard iron distortion is more of a contributor to the error of attitude estimation with magnetometers. Indoor environments or spaces inside ferrite-based structures, such as building reinforcements or a vehicle, often cause distortions with proximity. As positions correlate to areas of distortion, methods of magnetometer localization include the production of spatial mapping of magnetic field and collection of distortion signatures to better aid location tracking. The goal of this paper is to compare magnetometer methods that don't need pre-productions of magnetic field maps. Mapping the magnetic field in some spaces can be costly and inefficient. Dynamic measurement fusion is used to track the motion of a multi-link system with us. Conventional calibration by data collection of rotation at a static point, real-time estimation of calibration parameters each time step, and using two magnetometers for determining local hard iron distortion are compared to confirm the robustness and accuracy of each technique. With opposite-facing magnetometers, hard iron distortion can be accounted for regardless of position, Rather than assuming that hard iron distortion is constant regardless of positional change. The motion measured is a repeatable planar motion of a two-link system connected by revolute joints. The links are translated on a moving base to impulse rotation of the links. Equipping the joints with absolute encoders and recording the motion with cameras to enable ground truth comparison to each of the magnetometer methods. While the two-magnetometer method accounts for local hard iron distortion, the method fails where the magnetic field direction in space is inconsistent.Keywords: motion tracking, sensor fusion, magnetometer, state estimation
Procedia PDF Downloads 8413891 Health Tourists in Iran and Cultural Prejudices
Authors: Naeemeh Silvari
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The tourism industry is important for different nations in two ways. Apart from economic benefits, it provides a basis for getting acquainted with the culture of different regions of the world. Depending on the capacities and contexts of their geography, countries try to attract more people to their country in different ways. Health tourism has been an important branch of the tourism industry in recent years, and many countries around the world are trying to make progress in this field and attract many tourists from around the world. Iran, like many developing countries in the Middle East and East Asia, is trying to improve and develop tourist attractions in the field of health. Due to the cheapness of providing medical services to tourists, many people have traveled to Iran for medical and health care. However, there is a long way to go before recognizing and reaching the desired position in this field. Due to the direct relationship between tourism and culture, the negative attitude towards the context of Iran has caused foreign travelers not to choose this country as their tourist destination. In this article, we tried to study the change in their attitude towards Iran by using semi-structured interviews of foreign travelers who traveled to Iran for treatment and medical services. The text of the interviews was coded and analyzed by MAX QDA software. Many of the people in the sample were from Middle Eastern and Arabic-speaking countries. Influenced by the media, they felt rejected by the Iranians before the trip. During their stay in Iran and in connection with the health care staff, in the first stage, they pointed out that many of their anxieties about the kind of treatment of Iranians have been allayed. In addition to the satisfaction with the medical services provided, they considered the atmosphere of Iranians' interaction with foreign travelers to be relatively appropriate, and some stated that Iran would be the destination of their leisure trip in the future. At the end of the research, policymakers were suggested that in order to resolve cultural contradictions rooted in values, they should first be recognized and seek to use other opportunities to resolve contradictions and form interactions with other cultures.Keywords: cultural conflict, health tourism, cultural prejudice, advertising and media
Procedia PDF Downloads 7513890 Assessment of the Impacts of Climate Change on Climatic Zones over the Korean Peninsula for Natural Disaster Management Information
Authors: Sejin Jung, Dongho Kang, Byungsik Kim
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Assessing the impact of climate change requires the use of a multi-model ensemble (MME) to quantify uncertainties between scenarios and produce downscaled outlines for simulation of climate under the influence of different factors, including topography. This study decreases climate change scenarios from the 13 global climate models (GCMs) to assess the impacts of future climate change. Unlike South Korea, North Korea lacks in studies using climate change scenarios of the CoupledModelIntercomparisonProject (CMIP5), and only recently did the country start the projection of extreme precipitation episodes. One of the main purposes of this study is to predict changes in the average climatic conditions of North Korea in the future. The result of comparing downscaled climate change scenarios with observation data for a reference period indicates high applicability of the Multi-Model Ensemble (MME). Furthermore, the study classifies climatic zones by applying the Köppen-Geiger climate classification system to the MME, which is validated for future precipitation and temperature. The result suggests that the continental climate (D) that covers the inland area for the reference climate is expected to shift into the temperate climate (C). The coefficient of variation (CVs) in the temperature ensemble is particularly low for the southern coast of the Korean peninsula, and accordingly, a high possibility of the shifting climatic zone of the coast is predicted. This research was supported by a grant (MOIS-DP-2015-05) of Disaster Prediction and Mitigation Technology Development Program funded by Ministry of Interior and Safety (MOIS, Korea).Keywords: MME, North Korea, Koppen–Geiger, climatic zones, coefficient of variation, CV
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