Search results for: decent work agenda
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 14040

Search results for: decent work agenda

11850 Simulation of Stress in Graphite Anode of Lithium-Ion Battery: Intra and Inter-Particle

Authors: Wenxin Mei, Jinhua Sun, Qingsong Wang

Abstract:

The volume expansion of lithium-ion batteries is mainly induced by intercalation induced stress within the negative electrode, resulting in capacity degradation and even battery failure. Stress generation due to lithium intercalation into graphite particles is investigated based on an electrochemical-mechanical model in this work. The two-dimensional model presented is fully coupled, inclusive of the impacts of intercalation-induced stress, stress-induced intercalation, to evaluate the lithium concentration, stress generation, and displacement intra and inter-particle. The results show that the distribution of lithium concentration and stress exhibits an analogous pattern, which reflects the relation between lithium diffusion and stress. The results of inter-particle stress indicate that larger Von-Mises stress is displayed where the two particles are in contact with each other, and deformation at the edge of particles is also observed, predicting fracture. Additionally, the maximum inter-particle stress at the end of lithium intercalation is nearly ten times the intraparticle stress. And the maximum inter-particle displacement is increased by 24% compared to the single-particle. Finally, the effect of graphite particle arrangement on inter-particle stress is studied. It is found that inter-particle stress with tighter arrangement exhibits lower stress. This work can provide guidance for predicting the intra and inter-particle stress to take measures to avoid cracking of electrode material.

Keywords: electrochemical-mechanical model, graphite particle, lithium concentration, lithium ion battery, stress

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11849 Engineering a Tumor Extracellular Matrix Towards an in vivo Mimicking 3D Tumor Microenvironment

Authors: Anna Cameron, Chunxia Zhao, Haofei Wang, Yun Liu, Guang Ze Yang

Abstract:

Since the first publication in 1775, cancer research has built a comprehensive understanding of how cellular components of the tumor niche promote disease development. However, only within the last decade has research begun to establish the impact of non-cellular components of the niche, particularly the extracellular matrix (ECM). The ECM, a three-dimensional scaffold that sustains the tumor microenvironment, plays a crucial role in disease progression. Cancer cells actively deregulate and remodel the ECM to establish a tumor-promoting environment. Recent work has highlighted the need to further our understanding of the complexity of this cancer-ECM relationship. In vitro models use hydrogels to mimic the ECM, as hydrogel matrices offer biological compatibility and stability needed for long term cell culture. However, natural hydrogels are being used in these models verbatim, without tuning their biophysical characteristics to achieve pathophysiological relevance, thus limiting their broad use within cancer research. The biophysical attributes of these gels dictate cancer cell proliferation, invasion, metastasis, and therapeutic response. Evaluating the three most widely used natural hydrogels, Matrigel, collagen, and agarose gel, the permeability, stiffness, and pore-size of each gel were measured and compared to the in vivo environment. The pore size of all three gels fell between 0.5-6 µm, which coincides with the 0.1-5 µm in vivo pore size found in the literature. However, the stiffness for hydrogels able to support cell culture ranged between 0.05 and 0.3 kPa, which falls outside the range of 0.3-20,000 kPa reported in the literature for an in vivo ECM. Permeability was ~100x greater than in vivo measurements, due in large part to the lack of cellular components which impede permeation. Though, these measurements prove important when assessing therapeutic particle delivery, as the ECM permeability decreased with increasing particle size, with 100 nm particles exhibiting a fifth of the permeability of 10 nm particles. This work explores ways of adjusting the biophysical characteristics of hydrogels by changing protein concentration and the trade-off, which occurs due to the interdependence of these factors. The global aim of this work is to produce a more pathophysiologically relevant model for each tumor type.

Keywords: cancer, extracellular matrix, hydrogel, microfluidic

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11848 Analyzing the Effects of Bio-fibers on the Stiffness and Strength of Adhesively Bonded Thermoplastic Bio-fiber Reinforced Composites by a Mixed Experimental-Numerical Approach

Authors: Sofie Verstraete, Stijn Debruyne, Frederik Desplentere

Abstract:

Considering environmental issues, the interest to apply sustainable materials in industry increases. Specifically for composites, there is an emerging need for suitable materials and bonding techniques. As an alternative to traditional composites, short bio-fiber (cellulose-based flax) reinforced Polylactic Acid (PLA) is gaining popularity. However, these thermoplastic based composites show issues in adhesive bonding. This research focusses on analyzing the effects of the fibers near the bonding interphase. The research applies injection molded plate structures. A first important parameter concerns the fiber volume fraction, which directly affects adhesion characteristics of the surface. This parameter is varied between 0 (pure PLA) and 30%. Next to fiber volume fraction, the orientation of fibers near the bonding surface governs the adhesion characteristics of the injection molded parts. This parameter is not directly controlled in this work, but its effects are analyzed. Surface roughness also greatly determines surface wettability, thus adhesion. Therefore, this research work considers three different roughness conditions. Different mechanical treatments yield values up to 0.5 mm. In this preliminary research, only one adhesive type is considered. This is a two-part epoxy which is cured at 23 °C for 48 hours. In order to assure a dedicated parametric study, simple and reproduceable adhesive bonds are manufactured. Both single lap (substrate width 25 mm, thickness 3 mm, overlap length 10 mm) and double lap tests are considered since these are well documented and quite straightforward to conduct. These tests are conducted for the different substrate and surface conditions. Dog bone tensile testing is applied to retrieve the stiffness and strength characteristics of the substrates (with different fiber volume fractions). Numerical modelling (non-linear FEA) relates the effects of the considered parameters on the stiffness and strength of the different joints, obtained through the abovementioned tests. Ongoing work deals with developing dedicated numerical models, incorporating the different considered adhesion parameters. Although this work is the start of an extensive research project on the bonding characteristics of thermoplastic bio-fiber reinforced composites, some interesting results are already prominent. Firstly, a clear correlation between the surface roughness and the wettability of the substrates is observed. Given the adhesive type (and viscosity), it is noticed that an increase in surface energy is proportional to the surface roughness, to some extent. This becomes more pronounced when fiber volume fraction increases. Secondly, ultimate bond strength (single lap) also increases with increasing fiber volume fraction. On a macroscopic level, this confirms the positive effect of fibers near the adhesive bond line.

Keywords: adhesive bonding, bio-fiber reinforced composite, flax fibers, lap joint

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11847 Hearing Threshold Levels among Steel Industry Workers in Samut Prakan Province, Thailand

Authors: Petcharat  Kerdonfag, Surasak Taneepanichskul, Winai Wadwongtham

Abstract:

Industrial noise is usually considered as the main impact of the environmental health and safety because its exposure can cause permanently serious hearing damage. Despite providing strictly hearing protection standards and campaigning extensively encouraging public health awareness among industrial workers in Thailand, hazard noise-induced hearing loss has dramatically been massive obstacles for workers’ health. The aims of the study were to explore and specify the hearing threshold levels among steel industrial workers responsible in which higher noise levels of work zone and to examine the relationships of hearing loss and workers’ age and the length of employment in Samut Prakan province, Thailand. Cross-sectional study design was done. Ninety-three steel industrial workers in the designated zone of higher noise (> 85dBA) with more than 1 year of employment from two factories by simple random sampling and available to participate in were assessed by the audiometric screening at regional Samut Prakan hospital. Data of doing screening were collected from October to December, 2016 by the occupational medicine physician and a qualified occupational nurse. All participants were examined by the same examiners for the validity. An Audiometric testing was performed at least 14 hours after the last noise exposure from the workplace. Workers’ age and the length of employment were gathered by the developed occupational record form. Results: The range of workers’ age was from 23 to 59 years, (Mean = 41.67, SD = 9.69) and the length of employment was from 1 to 39 years, (Mean = 13.99, SD = 9.88). Fifty three (60.0%) out of all participants have been exposing to the hazard of noise in the workplace for more than 10 years. Twenty-three (24.7%) of them have been exposing to the hazard of noise less than or equal to 5 years. Seventeen (18.3%) of them have been exposing to the hazard of noise for 5 to 10 years. Using the cut point of less than or equal to 25 dBA of hearing thresholds, the average means of hearing thresholds for participants at 4, 6, and 8 kHz were 31.34, 29.62, and 25.64 dB, respectively for the right ear and 40.15, 32.20, and 25.48 dB for the left ear, respectively. The more developing age of workers in the work zone with hazard of noise, the more the hearing thresholds would be increasing at frequencies of 4, 6, and 8 kHz (p =.012, p =.026, p =.024) for the right ear, respectively and for the left ear only at the frequency 4 kHz (p =.009). Conclusion: The participants’ age in the hazard of noise work zone was significantly associated with the hearing loss in different levels while the length of participants’ employment was not significantly associated with the hearing loss. Thus hearing threshold levels among industrial workers would be regularly assessed and needed to be protected at the beginning of working.

Keywords: hearing threshold levels, hazard of noise, hearing loss, audiometric testing

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11846 Predictive Maintenance of Industrial Shredders: Efficient Operation through Real-Time Monitoring Using Statistical Machine Learning

Authors: Federico Pittino, Thomas Arnold

Abstract:

The shredding of waste materials is a key step in the recycling process towards the circular economy. Industrial shredders for waste processing operate in very harsh operating conditions, leading to the need for frequent maintenance of critical components. Maintenance optimization is particularly important also to increase the machine’s efficiency, thereby reducing the operational costs. In this work, a monitoring system has been developed and deployed on an industrial shredder located at a waste recycling plant in Austria. The machine has been monitored for one year, and methods for predictive maintenance have been developed for two key components: the cutting knives and the drive belt. The large amount of collected data is leveraged by statistical machine learning techniques, thereby not requiring very detailed knowledge of the machine or its live operating conditions. The results show that, despite the wide range of operating conditions, a reliable estimate of the optimal time for maintenance can be derived. Moreover, the trade-off between the cost of maintenance and the increase in power consumption due to the wear state of the monitored components of the machine is investigated. This work proves the benefits of real-time monitoring system for the efficient operation of industrial shredders.

Keywords: predictive maintenance, circular economy, industrial shredder, cost optimization, statistical machine learning

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11845 Environmental Impact Assessment of Ceramic Tile Materials Used in Jordan on Indoor Radon Level

Authors: Mefleh Hamideen

Abstract:

In this investigation, the activity concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰K, of some ceramic tile materials used in the local market of Jordan for interior decoration were determined by making use of High Purity Germanium (HPGe) detector. Twenty samples of the different countries of origin and sizes used in Jordan were analyzed. The concentration values of the last-mentioned radionuclides ranged from 30 Bq.kg⁻¹ (Sample from Jordan) to 98 Bq.kg⁻¹ (Sample from China) for ²²⁶Ra, 31 Bq.kg⁻¹ (Sample from Italy) to 98 Bq.kg⁻¹ (Sample from China) for ²³²Th, and 129 Bq.kg⁻¹ (Sample from Spain) to 679 Bq.kg⁻¹ (Sample from Italy) for ⁴⁰K. Based on the calculated activity concentrations, some radiological parameters have been calculated to test the radiation hazards in the ceramic tiles. In this work, the following parameters: Total absorbed dose rate (DR), Annual effective dose rate (HR), Radium equivalent activity (Raeq), Radon emanation coefficient F (%) and Radon mass exhalation rate (Em) were calculated for all ceramic tiles and listed in the body of the work. Fortunately, the average calculated values of all parameters are less than the recommended values for each parameter. Consequently, almost all the examined ceramic materials appear to have low radon emanation coefficients. As a result of that investigation, no problems on people can appear by using those ceramic tiles in Jordan.

Keywords: radon emanation coefficient, radon mass exhalation rate, total annual effective dose, radon level

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11844 Social Studies Teachers’ Sustained, Collaborative Professional Development Centered Round Innovative Curriculum Materials

Authors: Cory Callahan

Abstract:

Here the author synthesizes findings and implications from two research studies that comprise a continuing line of inquiry into the potential of an innovative professional development program to help in-service teachers understand and implement a complex model of social studies instruction. The paper specifically explores the question: To what degree can a collaborative professional development program centered around innovative curriculum materials help social studies teachers understand and implement a powerful social studies approach? Findings suggest the teachers increasingly incorporated substantive thinking (i.e., second-order historical domain knowledge) into their respective practice and they facilitated students’ use of historical photographs as evidence to begin to answer a compelling question. The teachers also began to effectively support students’ abilities to make claims about the past. Implications include the foregrounding of high-quality questions during planning and the need for explicit guidance in the form of structures and procedures (i.e., scaffolds) to help teachers systematically review students’ work products. The work shared here may contribute to scholarship that posits explanations for why teacher-support is routinely ineffectual and suggests ways to provide substantive collaborative support for in-service social studies teachers.

Keywords: educative curriculum, social studies, professional development, lesson study

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11843 Integration of a Microbial Electrolysis Cell and an Oxy-Combustion Boiler

Authors: Ruth Diego, Luis M. Romeo, Antonio Morán

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In the present work, a study of the coupling of a Bioelectrochemical System together with an oxy-combustion boiler is carried out; specifically, it proposes to connect the combustion gas outlet of a boiler with a microbial electrolysis cell (MEC) where the CO2 from the gases are transformed into methane in the cathode chamber, and the oxygen produced in the anode chamber is recirculated to the oxy-combustion boiler. The MEC mainly consists of two electrodes (anode and cathode) immersed in an aqueous electrolyte; these electrodes are separated by a proton exchange membrane (PEM). In this case, the anode is abiotic (where oxygen is produced), and it is at the cathode that an electroactive biofilm is formed with microorganisms that catalyze the CO2 reduction reactions. Real data from an oxy-combustion process in a boiler of around 20 thermal MW have been used for this study and are combined with data obtained on a smaller scale (laboratory-pilot scale) to determine the yields that could be obtained considering the system as environmentally sustainable energy storage. In this way, an attempt is made to integrate a relatively conventional energy production system (oxy-combustion) with a biological system (microbial electrolysis cell), which is a challenge to be addressed in this type of new hybrid scheme. In this way, a novel concept is presented with the basic dimensioning of the necessary equipment and the efficiency of the global process. In this work, it has been calculated that the efficiency of this power-to-gas system based on MEC cells when coupled to industrial processes is of the same order of magnitude as the most promising equivalent routes. The proposed process has two main limitations, the overpotentials in the electrodes that penalize the overall efficiency and the need for storage tanks for the process gases. The results of the calculations carried out in this work show that certain real potentials achieve an acceptable performance. Regarding the tanks, with adequate dimensioning, it is possible to achieve complete autonomy. The proposed system called OxyMES provides energy storage without energetically penalizing the process when compared to an oxy-combustion plant with conventional CO2 capture. According to the results obtained, this system can be applied as a measure to decarbonize an industry, changing the original fuel of the oxy-combustion boiler to the biogas generated in the MEC cell. It could also be used to neutralize CO2 emissions from industry by converting it to methane and then injecting it into the natural gas grid.

Keywords: microbial electrolysis cells, oxy-combustion, co2, power-to-gas

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11842 Modeling of Surface Roughness in Hard Turning of DIN 1.2210 Cold Work Tool Steel with Ceramic Tools

Authors: Mehmet Erdi Korkmaz, Mustafa Günay

Abstract:

Nowadays, grinding is frequently replaced with hard turning for reducing set up time and higher accuracy. This paper focused on mathematical modeling of average surface roughness (Ra) in hard turning of AISI L2 grade (DIN 1.2210) cold work tool steel with ceramic tools. The steel was hardened to 60±1 HRC after the heat treatment process. Cutting speed, feed rate, depth of cut and tool nose radius was chosen as the cutting conditions. The uncoated ceramic cutting tools were used in the machining experiments. The machining experiments were performed according to Taguchi L27 orthogonal array on CNC lathe. Ra values were calculated by averaging three roughness values obtained from three different points of machined surface. The influences of cutting conditions on surface roughness were evaluated as statistical and experimental. The analysis of variance (ANOVA) with 95% confidence level was applied for statistical analysis of experimental results. Finally, mathematical models were developed using the artificial neural networks (ANN). ANOVA results show that feed rate is the dominant factor affecting surface roughness, followed by tool nose radius and cutting speed.

Keywords: ANN, hard turning, DIN 1.2210, surface roughness, Taguchi method

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11841 Going beyond Stakeholder Participation

Authors: Florian Engel

Abstract:

Only with a radical change to an intrinsically motivated project team, through giving the employees the freedom for autonomy, mastery and purpose, it is then possible to develop excellent products. With these changes, combined with using a rapid application development approach, the group of users serves as an important indicator to test the market needs, rather than only as the stakeholders for requirements.

Keywords: intrinsic motivation, requirements elicitation, self-directed work, stakeholder participation

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11840 A Saltwater Battery Inspired by the Membrane Potential Found in Biological Cells

Authors: Ross Lee, Pritpal Singh, Andrew Jester

Abstract:

As the world transitions to a more sustainable energy economy, the deployment of energy storage technologies is expected to increase to develop a more resilient grid system. However, current technologies are associated with various environmental and safety issues throughout their entire lifecycle; therefore, new battery technology is necessary for grid applications to curtail these risks. Biological cells, such as human neurons and electrolytes in the electric eel, can serve as a more sustainable design template for a new bio-inspired (i.e., biomimetic) battery. Within biological cells, an electrochemical gradient across the cell membrane forms the membrane potential, which serves as the driving force for ion transport into/out of the cell, akin to the charging/discharging of a battery cell. This work serves as the first step to developing such a biomimetic battery cell, starting with the fabrication and characterization of ion-selective membranes to facilitate ion transport through the cell. Performance characteristics (e.g., cell voltage, power density, specific energy, roundtrip efficiency) for the cell under investigation are compared to incumbent battery technologies and biological cells to assess the readiness level for this emerging technology. Using a Na⁺-Form Nafion-117 membrane, the cell in this work successfully demonstrated behavior similar to human neurons; these findings will inform how cell components can be re-engineered to enhance device performance.

Keywords: battery, biomimetic, electrolytes, human neurons, ion-selective membranes, membrane potential

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11839 Fan-Subbing in East Asia: Audience Involvement in Transnational Media Flows

Authors: Jason D. Lin, Christine Sim

Abstract:

This paper examines the nature of transnational media flows in East Asia, specifically expounding on the popularity of Korean dramas in China and Taiwan. Situated in interdisciplinary academic work from cultural studies, media studies, and linguistics, this project locates the significance of certain genres and regions in determining why some are subject to flow while others remain within domestic borders. Moreover, transnational flows can take one of two routes –official translations and adaptations by media corporations and subtitles written by fans in online communities. The work of 'fan-subbing' has allowed for a more democratized showcase of what bilingual fans consume and are invested in sharing, rather than what major media companies deem relevant and monetizable. This reflects a culture of relatability driven by audiences rather than by corporate direction. Of course, a variety of technological, political, and economic factors play imperative roles in how both professional and fan-made subtitles flowed across borders and between nations. While fan-subbed media may be subject to criticism because of a lack of formal regulation, these limitations can, in some cases, be overcome by the agency afforded to audiences in the digital landscape. Finally, this paper offers a critical lens for deliberating the lasting impact of fan involvement on both professional practices and the flows of mainstream media throughout East Asia.

Keywords: audience studies, bilingual, cultural proximity, fan-subbing, online communities, subtitles

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11838 Effect of High Volume processed Fly Ash on Engineering Properties of Concrete

Authors: Dhara Shah, Chandrakant Shah

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As everyone knows, fly ash is a residual material we get upon energy production using coal. It has found numerous advantages for use in the concrete industry like improved workability, increased ultimate strength, reduced bleeding, reduced permeability, better finish and reduced heat of hydration. Types of fly ash depend on the type of coal and the coal combustion process. It is a pozzolanic material and has mainly two classes, F and C, based on the chemical composition. The fly ash used for this experimental work contains significant amount of lime and would be categorized as type F fly ash. Generally all types of fly ash have particle size less than 0.075mm. The fineness and lime content of fly ash are very important as they will affect the air content and water demand of the concrete, thereby affecting the durability and strength of the concrete. The present work has been done to optimize the use of fly ash to produce concrete with improved results and added benefits. A series of tests are carried out, analyzed and compared with concrete manufactured using only Portland cement as a binder. The present study is carried out for concrete mix with replacement of cement with different proportions of fly ash. Two concrete mixes M25 and M30 were studied with six replacements of cement with fly ash i.e. 40%, 45%, 50%, 55%, 60% and 65% for 7-day, 14-day, 28-day, 56-day and 90-day. Study focused on compressive strength, split tensile strength, modulus of elasticity and modulus of rupture of concrete. Study clearly revealed that cement replacement by any proportion of fly ash failed to achieve early strength. Replacement of 40% and 45% succeeded in achieving required flexural strength for M25 and M30 grade of concrete.

Keywords: processed fly ash, engineering properties of concrete, pozzolanic, lime content

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11837 The History and Pattern of Migration from Punjab to West: Colonial to Global Punjab

Authors: Malkit Singh

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This paper presents an in-depth analysis of the problem of migration from Punjab to the West while analyzing the history and patterns of generations of migration of Punjabis to the West. A special emphasis is given to link the present socio-economic and political crisis with the historical pattern of Punjabis’ migration to the West from colonial India to Independent Bharat, along with the stories of the success and failures of Western aspirants’ youth from Punjab. The roots of the migration from Punjab to the West have been traced from the invasion of the British in Punjab, resulting in the socio-economic and political dismantling of the Punjabi society, which resulted in the migration of the Punjabis to the other colonies of the British Empire. The grim position at home despite of all the efforts and hard work by the majority of the Punjabis, particularly from the farmer community and the shining lifestyle of some families of the village or vicinity who have some relatives in the West have encouraged the large number of Punjabis to change their fortune by working in West. However, the Visa and Work Permit regime has closed the doors of the West for those who are unskilled, semi-skilled and not qualified for the visa and work permit norms, but their inspiration to change their fortune by working abroad at any cost has resulted into the development of big business fraud of immigration agent and firms in Punjab that resulted into the loss of the thousands lives, imprisonment in the foreign and selling of the properties of the Punjabis. The greed for the greener pastures in the West and, the plight of the deserted wives of NRIs and the illegal routes adopted by the Punjabi youth due to the non-availability of visas and work permits are dealt in a comprehensive method. The rise and fall of Punjab as a land of the breadbasket of Bharat and the marginalization of the farmers with middle and small holdings due to the capital-intensive techniques are linked with the forced migration of the Punjabis. The failure of the government to address and respond to the rampant corruption, agriculture failure and the resulting problems of law and order before and after the troubled period of militancy in Punjab and the resulting migration to the West are comprehensively covered. The new trend of the Student Visa and Study abroad, particularly in Canada, Australia, and New Zealand, despite of the availability of quality education at very low cost in India. The early success of some students in getting study visas from Australia, Canada, New Zealand etc. and getting permanent immigration to these countries have encouraged the majority of Punjabi youth to leave their motherland for better opportunities in the prosperous lands, that is, again, failed as these countries are flooded with the Punjabi students. Moreover, the total failure of the political leadership of Punjab to address the basic needs of society, like law and order and stop the drug menace issues in the post-militancy Punjab is also done to understand the problem.

Keywords: Punjab, migration, West, agriculture

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11836 High Precision 65nm CMOS Rectifier for Energy Harvesting using Threshold Voltage Minimization in Telemedicine Embedded System

Authors: Hafez Fouad

Abstract:

Telemedicine applications have very low voltage which required High Precision Rectifier Design with high Sensitivity to operate at minimum input Voltage. In this work, we targeted 0.2V input voltage using 65 nm CMOS rectifier for Energy Harvesting Telemedicine application. The proposed rectifier which designed at 2.4GHz using two-stage structure found to perform in a better case where minimum operation voltage is lower than previous published paper and the rectifier can work at a wide range of low input voltage amplitude. The Performance Summary of Full-wave fully gate cross-coupled rectifiers (FWFR) CMOS Rectifier at F = 2.4 GHz: The minimum and maximum output voltages generated using an input voltage amplitude of 2 V are 490.9 mV and 1.997 V, maximum VCE = 99.85 % and maximum PCE = 46.86 %. The Performance Summary of Differential drive CMOS rectifier with external bootstrapping circuit rectifier at F = 2.4 GHz: The minimum and maximum output voltages generated using an input voltage amplitude of 2V are 265.5 mV (0.265V) and 1.467 V respectively, maximum VCE = 93.9 % and maximum PCE= 15.8 %.

Keywords: energy harvesting, embedded system, IoT telemedicine system, threshold voltage minimization, differential drive cmos rectifier, full-wave fully gate cross-coupled rectifiers CMOS rectifier

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11835 Determination of Mechanical Properties of Tomato Fruits: Experimental and Finite Element Analysis

Authors: Mallikarjunachari G., Venkata Ravi M.

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The objective of this research work is to evaluate the mechanical properties such as elastic modulus and critical rupture load of tomato fruits. Determination of mechanical properties of tomato fruits is essential in various material handling applications, especially as related to robot harvesting, packaging, and transportation. However, extracting meaningful mechanical properties of tomato fruits are extremely challenging due to its layered structure, i.e., the combination of exocarp, mesocarp, and locular gel tissues. Apart from this layered structure, other physical parameters such as diameter, sphericity, locule number, and, the surface to volume ratio also influence the mechanical properties. In this research work, tomato fruits are cultivated in two different ways, namely organic and inorganic farming. Static compression tests are performed to extract the mechanical properties of tomato fruits. Finite element simulations are done to complement the experimental results. It is observed that the effective modulus decreases as the compression depth increase from 0.5 mm to 10 mm and also a critical load of fracture decreases as the locule number increases from 3 to 5. Significant differences in mechanical properties are observed between organically and inorganically cultivated tomato fruits. The current study significantly helps in the design of material handling systems to avoid damage of tomato fruits.

Keywords: elastic modulus, critical load of fracture, locule number, finite element analysis

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11834 Mathematical Study for Traffic Flow and Traffic Density in Kigali Roads

Authors: Kayijuka Idrissa

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This work investigates a mathematical study for traffic flow and traffic density in Kigali city roads and the data collected from the national police of Rwanda in 2012. While working on this topic, some mathematical models were used in order to analyze and compare traffic variables. This work has been carried out on Kigali roads specifically at roundabouts from Kigali Business Center (KBC) to Prince House as our study sites. In this project, we used some mathematical tools to analyze the data collected and to understand the relationship between traffic variables. We applied the Poisson distribution method to analyze and to know the number of accidents occurred in this section of the road which is from KBC to Prince House. The results show that the accidents that occurred in 2012 were at very high rates due to the fact that this section has a very narrow single lane on each side which leads to high congestion of vehicles, and consequently, accidents occur very frequently. Using the data of speeds and densities collected from this section of road, we found that the increment of the density results in a decrement of the speed of the vehicle. At the point where the density is equal to the jam density the speed becomes zero. The approach is promising in capturing sudden changes on flow patterns and is open to be utilized in a series of intelligent management strategies and especially in noncurrent congestion effect detection and control.

Keywords: statistical methods, traffic flow, Poisson distribution, car moving technics

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11833 Standalone Docking Station with Combined Charging Methods for Agricultural Mobile Robots

Authors: Leonor Varandas, Pedro D. Gaspar, Martim L. Aguiar

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One of the biggest concerns in the field of agriculture is around the energy efficiency of robots that will perform agriculture’s activity and their charging methods. In this paper, two different charging methods for agricultural standalone docking stations are shown that will take into account various variants as field size and its irregularities, work’s nature to which the robot will perform, deadlines that have to be respected, among others. Its features also are dependent on the orchard, season, battery type and its technical specifications and cost. First charging base method focuses on wireless charging, presenting more benefits for small field. The second charging base method relies on battery replacement being more suitable for large fields, thus avoiding the robot stop for recharge. Existing many methods to charge a battery, the CC CV was considered the most appropriate for either simplicity or effectiveness. The choice of the battery for agricultural purposes is if most importance. While the most common battery used is Li-ion battery, this study also discusses the use of graphene-based new type of batteries with 45% over capacity to the Li-ion one. A Battery Management Systems (BMS) is applied for battery balancing. All these approaches combined showed to be a promising method to improve a lot of technical agricultural work, not just in terms of plantation and harvesting but also about every technique to prevent harmful events like plagues and weeds or even to reduce crop time and cost.

Keywords: agricultural mobile robot, charging methods, battery replacement method, wireless charging method

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11832 Impact of Welding Distortion on the Design of Fabricated T-Girders Using Finite Element Modeling

Authors: Ahmed Hammad, Yehia Abdel-Nasser, Mohamed Shamma

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The main configuration of ship construction consists of standard and fabricated stiffening members which are commonly used in shipbuilding such as fabricated T-sections. During the welding process, the non-uniform heating and rapid cooling lead to the inevitable presence of out-of-plane distortion and welding induced residual stresses. Because of these imperfections, the fabricated structural members may not attain their design load to be carried. The removal of these imperfections will require extra man-hours. In the present work, controlling these imperfections has been investigated at both design and fabrication stages. A typical fabricated T-girder is selected to investigate the problem of these imperfections using double-side welding. A numerical simulation based on finite element (FE) modeling has been used to investigate the effect of different parameters of the selected fabricated T-girder such as geometrical properties and welding sequences on the magnitude of welding imperfections. FE results were compared with the results of experimental model of a double-side fillet weld. The present work concludes that: Firstly, in the design stage, the optimum geometry of the fabricated T- girder is determined based on minimum steel weight and out- of- plane distortion. Secondly, in the fabrication stage, the best welding sequence is determined on the basis of minimum welding out- of- plane distortion.

Keywords: fabricated T-girder, FEM, out-of-plane distortion, section modulus, welding residual stresses

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11831 Structural Modeling and Experimental-Numerical Correlation of the Dynamic Behavior of the Portuguese Guitar by Using a Structural-Fluid Coupled Model

Authors: M. Vieira, V. Infante, P. Serrão, A. Ribeiro

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The Portuguese guitar is a pear-shaped plucked chordophone particularly known for its role in Fado, the most distinctive traditional Portuguese musical style. The acknowledgment of the dynamic behavior of the Portuguese guitar, specifically of its modal and mode shape response, has been the focus of different authors. In this research, the experimental results of the dynamic behavior of the guitar, which were previously obtained, are correlated with a vibro-acoustic finite element model of the guitar. The modelling of the guitar offered several challenges which are presented in this work. The results of the correlation between experimental and numerical data are presented and indicate good correspondence for the studied mode shapes. The influence of the air inside the chamber, for the finite element analysis, is shown to be crucial to understand the low-frequency modes of the Portuguese guitar, while, for higher frequency modes, the geometry of the guitar assumes greater relevance. Comparison is made with the classical guitar, providing relevant information about the intrinsic differences between the two, such as between its tones and other acoustical properties. These results represent a sustained base for future work, which will allow the study of the influence of different location and geometry of diverse components of the Portuguese guitar, being as well an asset to the comprehension of its musical properties and qualities and may, furthermore, represent an advantage for its players and luthiers.

Keywords: dynamic behavior of guitars, instrument acoustics, modal analysis, Portuguese guitar

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11830 Child of the Dark by Carolina Maria De Jesus in a Fundamental Rights Perspective

Authors: Eliziane Navarro, Aparecida Citta

Abstract:

Child of the dark is the work of the Brazilian author Carolina Maria de Jesus published at the first time by Ática & Francisco Alves in 1960. It is, mostly, a story of lack of rights. It lacks to men who live in the slums what is essential in order to take advantage of the privilege of rationality to develop themselves as civilized humans. It is, therefore, in the withholding of the basic rights that inequality finds space to build itself to be the main misery on Earth. Antonio Candido, a Brazilian sociologist, claims that it is the right to literature has the ability to humanize men, once the aptitude to create fiction and fable is essential to the social balance. Hence, for the forming role that literature holds, it must be thought as the number of rights that assure human dignity, such as housing, education, health, freedom, etc. When talking about her routine, Carolina puts in evidence something that has great influence over the formation of human beings, contributing to the way they live: the slum. Even though it happens in a distinct way and using her linguistics variation, Carolina writes about something that will only be discussed later on Brazil’s Cities Statute and Ermia Maricato: the right to the city, and how the slums are, although inserted in the city, an attachment, an illegal city, a dismissing room. It interests ourselves, for that matter, in this work, to analyse how the deprivation of the rights to the city and literature, detailed in Carolina’s journal, conditions human beings to a life where the instincts overcome the social values.

Keywords: Child of the dark, slum, Brazil, architecture and literature

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11829 Teachers Handbook: A Key to Imparting Teaching in Multilingual Classrooms at Kalinga Institute of Social Sciences (KISS)

Authors: Sushree Sangita Mohanty

Abstract:

The pedagogic system, which is used to work with indigenous groups, who have equally different socio-economic, socio-cultural & multi-lingual conditions with differing cognitive capabilities, makes the education situation complex. As a result, educating the indigenous people became just the dissemination of facts and information, but advancement in knowledge and possibilities somewhere hides. This gap arises complexities due to the language barrier and the teachers from a conventional background of teaching practices are unable to understand or connect with the students in the schools. This paper presents the research work of the Mother Tongue Based Multilingual Education (MTB-MLE) project that has developed a creative pedagogic endeavor for the students of Kalinga Institute of Social Sciences (KISS) for facilitating Multilingual Education (MLE) teaching. KISS is a home for 25,000 indigenous children. The students enrolled here are from 62 different indigenous communities who speak around 24 different languages with geographical articulation. The book contents include concept, understanding languages, similitudes among languages, the need of mother tongue in teaching and learning, skill development (Listening-Speaking-Reading-Writing), teachers activities for teaching in multilingual schools, the process of teaching, training format of multilingual teaching and procedures for basic data collection regarding multilingual schools and classroom handle.

Keywords: indigenous, multi-lingual, pedagogic, teachers, teaching practices

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11828 Potential Use of Local Materials as Synthesizing One Part Geopolymer Cement

Authors: Areej Almalkawi, Sameer Hamadna, Parviz Soroushian, Nalin Darsana

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The work on indigenous binders in this paper focused on the following indigenous raw materials: red clay, red lava and pumice (as primary aluminosilicate precursors), wood ash and gypsum (as supplementary minerals), and sodium sulfate and lime (as alkali activators). The experimental methods used for evaluation of these indigenous raw materials included laser granulometry, x-ray fluorescence (XRF) spectroscopy, and chemical reactivity. Formulations were devised for transforming these raw materials into alkali aluminosilicate-based hydraulic cements. These formulations were processed into hydraulic cements via simple heating and milling actions to render thermal activation, mechanochemical and size reduction effects. The resulting hydraulic cements were subjected to laser granulometry, heat of hydration and reactivity tests. These cements were also used to prepare mortar mixtures, which were evaluated via performance of compressive strength tests. The measured values of strength were correlated with the reactivity, size distribution and microstructural features of raw materials. Some of the indigenous hydraulic cements produced in this reporting period yielded viable levels of compressive strength. The correlation trends established in this work are being evaluated for development of simple and thorough methods of qualifying indigenous raw materials for use in production of indigenous hydraulic cements.

Keywords: one-part geopolymer cement, aluminosilicate precursors, thermal activation, mechanochemical

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11827 Tectonics in Sustainable Contemporary Architecture: An Approach to the Intersection between Design and Construction in the Work of Norman Foster

Authors: Mafalda Fabiene Ferreira Pantoja, Joao Da Costa Pantoja, Rui Humberto Costa De Fernandes Povoas

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The present paper seeks to present a theoretical and practical reflection about examples of contemporary architecture in the world context where concerns about the planet become prominent and increasingly necessary. Firstly, a brief introduction will be made on the conceptual principles of tectonics in architecture in order to apply such concepts in a perspective of analysis of the intersection between design and construction in contemporary examples of Norman Foster’s architecture, once his work has demonstrated attitudes of composition that concerns about the place, technology, materials, and building life. Foster's compositions are usually focused on the role of technology in the process of architectural design, making his works a mixture of place, program, construction, and formal structures. The main purpose of the present paper is the reflection on the tools of theoretical and practical analysis about tectonics, optimizing the resources that allow cultural anchoring and creation of identity. Also establishing relation between resources, building life cycle and employment of correct materials, in order to find out how the tectonic concept can elevate the status of contemporary architecture, making it qualitative in a more sustainable context and adapted to current needs.

Keywords: contemporary architecture, norman foster, tectonic, sustainable architecture

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11826 Semi-Analytic Method in Fast Evaluation of Thermal Management Solution in Energy Storage System

Authors: Ya Lv

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This article presents the application of the semi-analytic method (SAM) in the thermal management solution (TMS) of the energy storage system (ESS). The TMS studied in this work is fluid cooling. In fluid cooling, both effective heat conduction and heat convection are indispensable due to the heat transfer from solid to fluid. Correspondingly, an efficient TMS requires a design investigation of the following parameters: fluid inlet temperature, ESS initial temperature, fluid flow rate, working c rate, continuous working time, and materials properties. Their variation induces a change of thermal performance in the battery module, which is usually evaluated by numerical simulation. Compared to complicated computation resources and long computation time in simulation, the SAM is developed in this article to predict the thermal influence within a few seconds. In SAM, a fast prediction model is reckoned by combining numerical simulation with theoretical/empirical equations. The SAM can explore the thermal effect of boundary parameters in both steady-state and transient heat transfer scenarios within a short time. Therefore, the SAM developed in this work can simplify the design cycle of TMS and inspire more possibilities in TMS design.

Keywords: semi-analytic method, fast prediction model, thermal influence of boundary parameters, energy storage system

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11825 Floating Building Potential for Adaptation to Rising Sea Levels: Development of a Performance Based Building Design Framework

Authors: Livia Calcagni

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Most of the largest cities in the world are located in areas that are vulnerable to coastal erosion and flooding, both linked to climate change and rising sea levels (RSL). Nevertheless, more and more people are moving to these vulnerable areas as cities keep growing. Architects, engineers and policy makers are called to rethink the way we live and to provide timely and adequate responses not only by investigating measures to improve the urban fabric, but also by developing strategies capable of planning change, exploring unusual and resilient frontiers of living, such as floating architecture. Since the beginning of the 21st century we have seen a dynamic growth of water-based architecture. At the same time, the shortage of land available for urban development also led to reclaim the seabed or to build floating structures. In light of these considerations, time is ripe to consider floating architecture not only as a full-fledged building typology but especially as a full-fledged adaptation solution for RSL. Currently, there is no global international legal framework for urban development on water and there is no structured performance based building design (PBBD) approach for floating architecture in most countries, let alone national regulatory systems. Thus, the research intends to identify the technological, morphological, functional, economic, managerial requirements that must be considered in a the development of the PBBD framework conceived as a meta-design tool. As it is expected that floating urban development is mostly likely to take place as extension of coastal areas, the needs and design criteria are definitely more similar to those of the urban environment than of the offshore industry. Therefor, the identification and categorization of parameters takes the urban-architectural guidelines and regulations as the starting point, taking the missing aspects, such as hydrodynamics, from the offshore and shipping regulatory frameworks. This study is carried out through an evidence-based assessment of performance guidelines and regulatory systems that are effective in different countries around the world addressing on-land and on-water architecture as well as offshore and shipping industries. It involves evidence-based research and logical argumentation methods. Overall, this paper highlights how inhabiting water is not only a viable response to the problem of RSL, thus a resilient frontier for urban development, but also a response to energy insecurity, clean water and food shortages, environmental concerns and urbanization, in line with Blue Economy principles and the Agenda 2030. Moreover, the discipline of architecture is presented as a fertile field for investigating solutions to cope with climate change and its effects on life safety and quality. Future research involves the development of a decision support system as an information tool to guide the user through the decision-making process, emphasizing the logical interaction between the different potential choices, based on the PBBD.

Keywords: adaptation measures, floating architecture, performance based building design, resilient architecture, rising sea levels

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11824 Barriers to Job Localization Policy in Private Sector: Case Study from Oman

Authors: Yahya Al Nahdi

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Even though efforts to increase the participation of nationals in the workforce have been in place for more than a decade in the Sultanate of Oman, the results are not impressive. Citizens’ workforce participation – it is argued in the literature – is hindered by institutional, as well as attitudinal concerns. The purpose of this study was to determine barriers to Omanization (employment of Omani nationals) in the private sector as perceived by the senior managers in government and private sector. Data were collected predominantly through in-depth, semi-structured interviews with managers who directly deal with Omanization policies from both the public and private sector. Results from the data analysis have shown that the majority of participants acknowledged a work preference in the movement (public sector). The private sector employees' compensation and benefits package was perceived to be less attractive than that offered in the government (public sector). The negative perceptions (stereotypes) shared by expatriates regarding work attitudes and competencies of citizens in the local labour market was also overwhelmingly perceived as a major hindrance. Furthermore, institutional issues such as, ineffectiveness of rules and regulation regarding Omanization, inappropriate quota system and lack of public awareness towards private sector’s jobs, are also perceived problematic to successful Omanization. Finally, results from the data analysis were used in recommending strategies for potential consideration in the pursuit of a successful Omanization programme.

Keywords: localization, job security, labour force structure, Omanization, private sector, public sector

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11823 Optimization of End Milling Process Parameters for Minimization of Surface Roughness of AISI D2 Steel

Authors: Pankaj Chandna, Dinesh Kumar

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The present work analyses different parameters of end milling to minimize the surface roughness for AISI D2 steel. D2 Steel is generally used for stamping or forming dies, punches, forming rolls, knives, slitters, shear blades, tools, scrap choppers, tyre shredders etc. Surface roughness is one of the main indices that determines the quality of machined products and is influenced by various cutting parameters. In machining operations, achieving desired surface quality by optimization of machining parameters, is a challenging job. In case of mating components the surface roughness become more essential and is influenced by the cutting parameters, because, these quality structures are highly correlated and are expected to be influenced directly or indirectly by the direct effect of process parameters or their interactive effects (i.e. on process environment). In this work, the effects of selected process parameters on surface roughness and subsequent setting of parameters with the levels have been accomplished by Taguchi’s parameter design approach. The experiments have been performed as per the combination of levels of different process parameters suggested by L9 orthogonal array. Experimental investigation of the end milling of AISI D2 steel with carbide tool by varying feed, speed and depth of cut and the surface roughness has been measured using surface roughness tester. Analyses of variance have been performed for mean and signal-to-noise ratio to estimate the contribution of the different process parameters on the process.

Keywords: D2 steel, orthogonal array, optimization, surface roughness, Taguchi methodology

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11822 The Effect of Air Filter Performance on Gas Turbine Operation

Authors: Iyad Al-Attar

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Air filters are widely used in gas turbines applications to ensure that the large mass (500kg/s) of clean air reach the compressor. The continuous demand of high availability and reliability has highlighted the critical role of air filter performance in providing enhanced air quality. In addition to being challenged with different environments [tropical, coastal, hot], gas turbines confront wide array of atmospheric contaminants with various concentrations and particle size distributions that would lead to performance degradation and components deterioration. Therefore, the role of air filters is of a paramount importance since fouled compressor can reduce power output and availability of the gas turbine to over 70 % throughout operation. Consequently, accurate filter performance prediction is critical tool in their selection considering their role in minimizing the economic impact of outages. In fact, actual performance of Efficient Particulate Air [EPA] filters used in gas turbine tend to deviate from the performance predicted by laboratory results. This experimental work investigates the initial pressure drop and fractional efficiency curves of full-scale pleated V-shaped EPA filters used globally in gas turbine. The investigation involved examining the effect of different operational conditions such as flow rates [500 to 5000 m3/h] and design parameters such as pleat count [28, 30, 32 and 34 pleats per 100mm]. This experimental work has highlighted the underlying reasons behind the reduction in filter permeability due to the increase of flow rates and pleat density. The reasons, which led to surface area losses of filtration media, are due to one or combination of the following effects: pleat-crowding, deflection of the entire pleated panel, pleat distortion at the corner of the pleat and/or filtration medium compression. This paper also demonstrates that the effect of increasing the flow rate has more pronounced effect on filter performance compared to pleating density. This experimental work suggests that a valid comparison of the pleat densities should be based on the effective surface area, namely, the area that participates in the filtration process, and not the total surface area the pleat density provides. Throughout this study, optimal pleat count that satisfies both initial pressure drop and efficiency requirements may not have necessarily existed.

Keywords: filter efficiency, EPA Filters, pressure drop, permeability

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11821 Employee Happiness: The Influence of Providing Consumers with an Experience versus an Object

Authors: Wilson Bastos, Sigal G. Barsade

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Much of what happens in the marketplace revolves around the provision and consumption of goods. Recent research has advanced a useful categorization of these goods—as experiential versus material—and shown that, from the consumers’ perspective, experiences (e.g., a theater performance) are superior to objects (e.g., an electronic gadget) in offering various social and psychological benefits. A common finding in this growing research stream is that consumers gain more happiness from the experiences they have than the objects they own. By focusing solely on those acquiring the experiential or material goods (the consumers), prior research has remained silent regarding another important group of individuals—those providing the goods (the employees). Do employees whose jobs are primarily focused on offering consumers an experience (vs. object) also gain more happiness from their occupation? We report evidence from four experiments supporting an experiential-employee advantage. Further, we use mediation and moderation tests to unearth the mechanism responsible for this effect. Results reveal that work meaningfulness is the primary driver of the experiential-employee advantage. Overall, our findings suggest that employees find it more meaningful to provide people with an experience as compared to a material object, which in turn shapes the happiness they derive from their jobs. We expect this finding to have implications on human development, and to be of relevance to researchers and practitioners interested in how to advance human condition in the workplace.

Keywords: employee happiness, experiential versus material jobs, work meaningfulness

Procedia PDF Downloads 271