Search results for: safety performance functions
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 17246

Search results for: safety performance functions

9956 Great Food, No Atmosphere: A Review of Performance Nutrition for Application to Extravehicular Activities in Spaceflight

Authors: Lauren E. Church

Abstract:

Background: Extravehicular activities (EVAs) are a critical aspect of missions aboard the International Space Station (ISS). It has long been noted that the spaceflight environment and the physical demands of EVA cause physiological and metabolic changes in humans; this review aims to combine these findings with nutritional studies in analogues of the spaceflight and EVA environments to make nutritional recommendations for astronauts scheduled for and immediately returning from EVAs. Results: Energy demands increase during orbital spaceflight and see further increases during EVA. Another critical element of EVA nutrition is adequate hydration. Orbital EVA appears to provide adequate hydration under current protocol, but during lunar surface EVA (LEVA) and in a 10km lunar walk-back test astronauts have stated that up to 20% more water was needed. Previous attempts for in-suit edible sustenance have not been adequately taken up by astronauts to be economically viable. In elite endurance athletes, a mixture of glucose and fructose is used in gels, improving performance. Discussion: A combination of non-caffeinated energy drink and simple water should be available for astronauts during EVA, allowing more autonomy. There should also be provision of gels or a similar product containing appropriate sodium levels to maintain hydration, but not so much as to hyperhydrate through renal water reabsorption. It is also suggested that short breaks be built into the schedule of EVAs for these gels to be consumed, as it is speculated that reason for low uptake of in-suit sustenance is the lack of time available in which to consume it.

Keywords: astronaut, nutrition, space, sport

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9955 Tandem Concentrated Photovoltaic-Thermoelectric Hybrid System: Feasibility Analysis and Performance Enhancement Through Material Assessment Methodology

Authors: Shuwen Hu, Yuancheng Lou, Dongxu Ji

Abstract:

Photovoltaic (PV) power generation, as one of the most commercialized methods to utilize solar power, can only convert a limited range of solar spectrum into electricity, whereas the majority of the solar energy is dissipated as heat. To address this problem, thermoelectric (TE) module is often integrated with the concentrated PV module for waste heat recovery and regeneration. In this research, a feasibility analysis is conducted for the tandem concentrated photovoltaic-thermoelectric (CPV-TE) hybrid system considering various operational parameters as well as TE material properties. Furthermore, the power output density of the CPV-TE hybrid system is maximized by selecting the optimal TE material with application of a systematic assessment methodology. In the feasibility analysis, CPV-TE is found to be more advantageous than sole CPV system except under high optical concentration ratio with low cold side convective coefficient. It is also shown that the effects of the TE material properties, including Seebeck coefficient, thermal conductivity, and electrical resistivity, on the feasibility of CPV-TE are interacted with each other and might have opposite effect on the system performance under different operational conditions. In addition, the optimal TE material selected by the proposed assessment methodology can improve the system power output density by 227 W/m2 under highly concentrated solar irradiance hence broaden the feasible range of CPV-TE considering optical concentration ratio.

Keywords: feasibility analysis, material assessment methodology, photovoltaic waste heat recovery, tandem photovoltaic-thermoelectric

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9954 Global Navigation Satellite System and Precise Point Positioning as Remote Sensing Tools for Monitoring Tropospheric Water Vapor

Authors: Panupong Makvichian

Abstract:

Global Navigation Satellite System (GNSS) is nowadays a common technology that improves navigation functions in our life. Additionally, GNSS is also being employed on behalf of an accurate atmospheric sensor these times. Meteorology is a practical application of GNSS, which is unnoticeable in the background of people’s life. GNSS Precise Point Positioning (PPP) is a positioning method that requires data from a single dual-frequency receiver and precise information about satellite positions and satellite clocks. In addition, careful attention to mitigate various error sources is required. All the above data are combined in a sophisticated mathematical algorithm. At this point, the research is going to demonstrate how GNSS and PPP method is capable to provide high-precision estimates, such as 3D positions or Zenith tropospheric delays (ZTDs). ZTDs combined with pressure and temperature information allows us to estimate the water vapor in the atmosphere as precipitable water vapor (PWV). If the process is replicated for a network of GNSS sensors, we can create thematic maps that allow extract water content information in any location within the network area. All of the above are possible thanks to the advances in GNSS data processing. Therefore, we are able to use GNSS data for climatic trend analysis and acquisition of the further knowledge about the atmospheric water content.

Keywords: GNSS, precise point positioning, Zenith tropospheric delays, precipitable water vapor

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9953 Perceived Self-Efficacy of Children with Characteristics of Giftedness

Authors: Cristina Costa-Lobo, Ana Medeiros, Ana Campina

Abstract:

This study refers to the appropriateness of the psychopedagogical intervention programs focused on the adjustment and psychological well-being of children with characteristics of giftedness and the interests of promoting specialized and permanent follow-up to these children. It was intended to find out the impact on perceived self-efficacy in children with characteristics of giftedness after the frequency of a psychopedagogical intervention program. For this was applied to Multidimensional Scale Perceived Self-Efficacy, in two times (pre and post program frequency), in a quasi-experimental design. Innovative data are presented in reports to the relationship of perceived self-efficacy with giftedness, highlighting the evidence of this program focusing on the development of personal, social and emotional skills, applied to 20 children with characteristics of giftedness, in Northern Portugal, in the 2014-2015 school year, have no influence on perceived self-efficacy of children with characteristics of giftedness. The main implication of this research is congruent with the conclusions of studies that point that the greatest challenge in the education of children with characteristics of giftedness is to extend the traditional investment in intellectual production and creative capital to include an equal investment in social capital and the development of competencies of executive functions, dimensions that development programs stimulate. This study appeals to the need of children with characteristics of giftedness to be targets of psychopedagogical intervention programs with the constant specialization and constant updating of the knowledge of the professionals who work with them, motivated by being individuals with such specific and ever-changing characteristics reflecting an inclusive school life.

Keywords: giftedness, perceived self-efficacy, EMAEP, psychopedagogical intervention programs

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9952 Coarse-Grained Computational Fluid Dynamics-Discrete Element Method Modelling of the Multiphase Flow in Hydrocyclones

Authors: Li Ji, Kaiwei Chu, Shibo Kuang, Aibing Yu

Abstract:

Hydrocyclones are widely used to classify particles by size in industries such as mineral processing and chemical processing. The particles to be handled usually have a broad range of size distributions and sometimes density distributions, which has to be properly considered, causing challenges in the modelling of hydrocyclone. The combined approach of Computational Fluid Dynamics (CFD) and Discrete Element Method (DEM) offers convenience to model particle size/density distribution. However, its direct application to hydrocyclones is computationally prohibitive because there are billions of particles involved. In this work, a CFD-DEM model with the concept of the coarse-grained (CG) model is developed to model the solid-fluid flow in a hydrocyclone. The DEM is used to model the motion of discrete particles by applying Newton’s laws of motion. Here, a particle assembly containing a certain number of particles with same properties is treated as one CG particle. The CFD is used to model the liquid flow by numerically solving the local-averaged Navier-Stokes equations facilitated with the Volume of Fluid (VOF) model to capture air-core. The results are analyzed in terms of fluid and solid flow structures, and particle-fluid, particle-particle and particle-wall interaction forces. Furthermore, the calculated separation performance is compared with the measurements. The results obtained from the present study indicate that this approach can offer an alternative way to examine the flow and performance of hydrocyclones

Keywords: computational fluid dynamics, discrete element method, hydrocyclone, multiphase flow

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9951 Experimental Investigation of Heat Pipe with Annular Fins under Natural Convection at Different Inclinations

Authors: Gangacharyulu Dasaroju, Sumeet Sharma, Sanjay Singh

Abstract:

Heat pipe is characterised as superconductor of heat because of its excellent heat removal ability. The operation of several engineering system results in generation of heat. This may cause several overheating problems and lead to failure of the systems. To overcome this problem and to achieve desired rate of heat dissipation, there is need to study the performance of heat pipe with annular fins under free convection at different inclinations. This study demonstrates the effect of different mass flow rate of hot fluid into evaporator section on the condenser side heat transfer coefficient with annular fins under natural convection at different inclinations. In this study annular fins are used for the experimental work having dimensions of length of fin, thickness of fin and spacing of fin as 10 mm, 1 mm and 6 mm, respectively. The main aim of present study is to discover at what inclination angles the maximum heat transfer coefficient shall be achieved. The heat transfer coefficient on the external surface of heat pipe condenser section is determined by experimental method and then predicted by empirical correlations. The results obtained from experimental and Churchill and Chu relation for laminar are in fair agreement with not more than 22% deviation. It is elucidated the maximum heat transfer coefficient of 31.2 W/(m2-K) at 25˚ tilt angle and minimal condenser heat transfer coefficient of 26.4 W/(m2-K) is seen at 45˚ tilt angle and 200 ml/min mass flow rate. Inclination angle also affects the thermal performance of heat pipe. Beyond 25o inclination, heat transport rate starts to decrease.

Keywords: heat pipe, annular fins, natural convection, condenser heat transfer coefficient, tilt angle

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9950 Digital Design and Practice of The Problem Based Learning in College of Medicine, Qassim University, Saudi Arabia

Authors: Ahmed Elzainy, Abir El Sadik, Waleed Al Abdulmonem, Ahmad Alamro, Homaidan Al-Homaidan

Abstract:

Problem-based learning (PBL) is an educational modality which stimulates critical and creative thinking. PBL has been practiced in the college of medicine, Qassim University, Saudi Arabia, since the 2002s with offline face to face activities. Therefore, crucial technological changes in paperless work were needed. The aim of the present study was to design and implement the digitalization of the PBL activities and to evaluate its impact on students' and tutors’ performance. This approach promoted the involvement of all stakeholders after their awareness of the techniques of using online tools. IT support, learning resources facilities, and required multimedia were prepared. Students’ and staff perception surveys reflected their satisfaction with these remarkable changes. The students were interested in the new digitalized materials and educational design, which facilitated the conduction of PBL sessions and provided sufficient time for discussion and peer sharing of knowledge. It enhanced the tutors for supervision and tracking students’ activities on the Learning Management System. It could be concluded that introducing of digitalization of the PBL activities promoted the students’ performance, engagement and enabled a better evaluation of PBL materials and getting prompt students as well as staff feedback. These positive findings encouraged the college to implement the digitalization approach in other educational activities, such as Team-Based Learning, as an additional opportunity for further development.

Keywords: multimedia in PBL, online PBL, problem-based learning, PBL digitalization

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9949 Closed-Loop Supply Chain: A Study of Bullwhip Effect Using Simulation

Authors: Siddhartha Paul, Debabrata Das

Abstract:

Closed-loop supply chain (CLSC) management focuses on integrating forward and reverse flow of material as well as information to maximize value creation over the entire life-cycle of a product. Bullwhip effect in supply chain management refers to the phenomenon where a small variation in customers’ demand results in larger variation of orders at the upstream levels of supply chain. Since the quality and quantity of products returned to the collection centers (as a part of reverse logistics process) are uncertain, bullwhip effect is inevitable in CLSC. Therefore, in the present study, first, through an extensive literature survey, we identify all the important factors related to forward as well as reverse supply chain which causes bullwhip effect in CLSC. Second, we develop a system dynamics model to study the interrelationship among the factors and their effect on the performance of overall CLSC. Finally, the results of the simulation study suggest that demand forecasting, lead times, information sharing, inventory and work in progress adjustment rate, supply shortages, batch ordering, price variations, erratic human behavior, parameter correcting, delivery time delays, return rate of used products, manufacturing and remanufacturing capacity constraints are the important factors which have a significant influence on system’s performance, specifically on bullwhip effect in a CLSC.

Keywords: bullwhip effect, closed-loop supply chain, system dynamics, variance ratio

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9948 Levels of Selected Heavy Metals in Varieties of Vegetable oils Consumed in Kingdom of Saudi Arabia and Health Risk Assessment of Local Population

Authors: Muhammad Waqar Ashraf

Abstract:

Selected heavy metals, namely Cu, Zn, Fe, Mn, Cd, Pb, and As, in seven popular varieties of edible vegetable oils collected from Saudi Arabia, were determined by graphite furnace atomic absorption spectrometry (GF-AAS) using microwave digestion. The accuracy of procedure was confirmed by certified reference materials (NIST 1577b). The concentrations for copper, zinc, iron, manganese, lead and arsenic were observed in the range of 0.035 - 0.286, 0.955 - 3.10, 17.3 - 57.8, 0.178 - 0.586, 0.011 - 0.017 and 0.011 - 0.018 µg/g, respectively. Cadmium was found to be in the range of 2.36 - 6.34 ng/g. The results are compared internationally and with standards laid down by world health agencies. A risk assessment study has been carried out to assess exposure to these metals via consumption of vegetable oils. A comparison has been made with safety intake levels for these heavy metals recommended by Institute of Medicine of the National Academies (IOM), US Environmental Protection Agency (US EPA) and Joint FAO/WHO Expert Committee on Food Additives (JECFA). The results indicated that the dietary intakes of the selected heavy metals from daily consumption of 25 g of edible vegetable oils for a 70 kg individual should pose no significant health risk to local population.

Keywords: vegetable oils, heavy metals, contamination, health risk assessment

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9947 Design of Structure for a Heavy-Duty Mineral Tow Machine by Evaluating the Dynamic and Static Loads

Authors: M. Akhondizadeh, Mohsen Khajoei, Mojtaba Khajoei

Abstract:

The purpose of the present work was the design of a towing machine which was decided to be manufactured by Arman Gohar-e-Sirjan company in the Gol-e-Gohar iron ore complex in Iran. The load analysis has been conducted to determine the static and dynamic loads at the critical conditions. The inertial forces due to the velocity increment and road bump have been considered in load evaluation. The form of loading of the present machine is hauling and/or conveying the mineral machines on the mini ramp. Several stages of these forms of loading, from the initial touch of the tow and carried machine to the final position, have been assessed to determine the critical state. The stress analysis has been performed by the ANSYS software. Several geometries for the main load-carrying elements have been analyzed to have the optimum design by the minimum weight of the structure. Finally, a structure with a total weight of 38 tons has been designed with a static load-carrying capacity of 80 tons by considering the 40 tons additional capacity for dynamic effects. The stress analysis for 120 tons load gives the minimum safety factor of 1.18.

Keywords: mechanical design, stress analysis, tow structure, dynamic load, static load

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9946 Ideological Stance in Political Discourse: A Transitivity Analysis of Nawaz Sharif's Address at 71st UN Assembly

Authors: A. Nawaz

Abstract:

The present study uses Halliday’s transitivity model to analyze and interpret ideological stance in PM Nawaz Sharif’s political discourse. His famous speech at the 71st UN assembly was analyzed qualitatively using clausal analysis approach to investigate the communicative functions of the linguistic choices made in the address. The study discovers that among the six process types under the transitivity model, material, relational and mental processes appear most frequently in the speech, making up almost 86% of the whole. Verbal processes rank 4th, whereas existential and behavioral are the least occurring processes covering only 2 and 1 percent respectively. The dominant use of material processes suggests that Nawaz Sharif and his government are the main actors working on several concrete projects to produce a sense of developmental progression and continuity. Using relational and mental processes the PM, along with establishing proximity with masses and especially Kashmiri, gives guarantees and promises. The linguistic analysis concludes Kashmir dispute as being the central theme of the address, since it covers more than half of the discourse. The address calls for a strong action instead of formal assurances and wishful thoughts. The study establishes that language structures can yield certain connotations and ideologies which are not overt for readers. This is in affirmation to the supposition that language form performs a communicative function and is not merely fortuitous.

Keywords: Hallidian perspective on language, implicit meanings, Nawaz Sharif, political ideologies, political speeches, transitivity, UN Assembly

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9945 Comparison and Evaluation of Joomla and WordPress Web Content Management Systems for Effective Site Administration

Authors: Abubakar Ibrahim, Muhammad Garba, Adelusi Oluwaseyi Abiodun

Abstract:

Website development and administration has already become a very critical issue in many organisations due to the fact that most of the organisations have embraced the use of the internet to deliver their services and products seamlessly but even with huge advantages of being present on the internet, and website are very difficult and expensive to develop and maintain. In recent years, a number of open-source web Contents Management System (CMS) have been developed to allow organisations to internally develop and maintain their websites without the need to hire professional web developers to provide such services for them. This study aimed at performing a comparative analysis of the two most widely used open source CMS Joomla and wordpress, based on the following criteria: intuitiveness, responsiveness richness in features, meeting expectation, fill secured, ease of navigation, structure, and performance. Two identical applications were developed using the said CMS. In this study, a purposive sampling technique was adopted to administer the questionnaires, and a total of 50 respondents were selected to surf sites and fill out a questionnaire based on their experience on the two sites. Gt-matrix was used to carry out further analysis of the applications. The result shows that Joomla is the best for developing an e-commerce site due to the fact that it is best in terms of performance, better structure, meeting user expectations, rich features, and functionality. Even though Wordpress is intuitive and easy for navigation. One can still argue that Joomla is superior.

Keywords: open source, content management system, Joomla, WordPress

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9944 Functional Food Industry in Thailand: Perspectives from Government, Education, and Private Sector

Authors: Charintorn Suwannawong, Tananpon Yavilas, Sopida Boonaneksap, Chotika Viriyarattanasak, Chairath Tangduangdee

Abstract:

With increasing aging population and health conscious consumers, the demand for health promoting products such as functional foods, dietary supplements, and nutraceutical products has continuously increased in Thailand. Nevertheless, the strategic framework for regulatory functional food developments in Thailand is still unclear. The objective of this study was to survey stakeholders’ perspectives on three scopes, consisting of 1) the current status 2) obstacles, and 3) future trend for the development and production of functional foods in Thailand. A survey was conducted by interviewing ten experts from governmental organization, industrial sector and academic institute. The obtained results show that there is no established definition for functional foods in Thailand. There is a variety of raw materials that are capable to be potential ingredients for functional food production in Thailand and exported to global market. However, the scaling up technology into a commercial production is limited. Moreover, there is a need to establish the infrastructures, such as testing laboratory, and regulatory standards for quality control and ensuring product safety. This information is useful for government in the development of the strategic framework and policy statement on improvement of functional food industry in Thailand.

Keywords: functional foods, interview, perspective, Thailand

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9943 From Sound to Music: The Trajectory of Musical Semiotics in a Selected Soundscape Environment in South-Western Nigeria

Authors: Olatunbosun Samuel Adekogbe

Abstract:

This paper addresses the question of musical signification, revolving around nature and its natural divides; the paper tends to examine the roles of the dispositional apparatus of listeners to react to sounding environments through music as coordinated sound that focuses on the powerful strain between vibrational occurrences of sound and potentials of being structured. This paper sets out to examine music as a simple conventional design that does not allude to something beyond music and sound as a vehicle to communicate through production, perception, translation, and reaction with regard to melodic and semiotic functions of sounds. This paper adopts the application of questionnaire and evolutionary approach methods to probe musical adaptation, reproduction, and natural selection as the basis for explaining specific human behavioural responses to musical sense-making beyond the above-sketched dichotomies, with a major focus on the transition from acoustic-emotional sensibilities to musical meaning in the selected soundscapes. It was observed that music has emancipated itself from the level of mere acoustic processing of sounds to a functional description in terms of allowing music users to share experiences and interact with the soundscaping environment. The paper, therefore, concludes that the audience as music participants and listeners in the selected soundscapes have been conceived as adaptive devices in the paradigm shift, which can build up new semiotic linkages with the sounding environments in southwestern Nigeria.

Keywords: semiotics, sound, music, soundscape, environment

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9942 A Comprehensive Evaluation of the Bus Rapid Transit Project from Gazipur to Airport at Dhaka Focusing on Environmental Impacts

Authors: Swapna Begum, Higano Yoshiro

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Dhaka is the capital city of Bangladesh. It is considered as one of the traffic congested cities in the world. The growth of the population of this city is increasing day by day. The land use pattern and the increased socio-economic characteristics increase the motor vehicle ownership of this city. The rapid unplanned urbanization and poor transportation planning have deteriorated the transport environment of this city. Also, the huge travel demand with non-motorized traffics on streets is accounted for enormous traffic congestion in this city. The land transport sector in Dhaka is mainly dependent on road transport comprised of both motorized and non-motorized modes of travel. This improper modal mix and the un-integrated system have resulted in huge traffic congestion in this city. Moreover, this city has no well-organized public transport system and any Mass Transit System to cope with this ever increasing demand. Traffic congestion causes serious air pollution and adverse impact on the economy by deteriorating the accessibility, level of service, safety, comfort and operational efficiency. Therefore, there is an imperative need to introduce a well-organized, properly scheduled mass transit system like (Bus Rapid Transit) BRT minimizing the existing problems.

Keywords: air pollution, BRT, mass transit, traffic congestion

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9941 Tracking of Linarin from the Ethyl Acetate Fraction of Melinjo (Gnetum gnemon L.) Seeds Using Preparative High Performance Liquid Chromatography

Authors: Asep Sukohar, Ramadhan Triyandi, Muhammad Iqbal, Sahidin, Suharyani

Abstract:

Introduction: Resveratrol is a class of bioactive chemicals found in melinjo, which has a wide range of biological actions. The purpose of this study is to determine the linarin content of the melinjo fraksi by using preparative-high-performance liquid chromatography (prep-HPLC). Method: Extraction used the soxhletation method with 96% ethanol solvent. Fractionation used ethyl acetate and ethanol in a ratio of 1:1. Tracing of linarin compound used prep-HPLC with a mobile phase ratio of distilled water: methanol (55: 45, v/v). The presence of linarin was detected using a wavelength of 215 nm. Fourier Transform Infrared (FTIR) was used to identify the functional groups of compound. Result: The retention time required to elute the ethyl acetate fraction was 2.601 minutes. Compound separation identification using Fourier Transform Infrared Spectroscopy - Quest Attenuated Total Reflectance (FTIR - QATR) has a similarity value range with standards from 0 to 1000. The elution results of the ethyl acetate fraction have similar values with the standard compounds linarin (668), resveratrol (578), and catechin (455). Conclusion: Tracing for active compound in the ethyl acetate fraction of Gnetum Gnemon L. using prep-HPLC showed a strong suspicion of the presence of linarin compound.

Keywords: Gnetum gnemon L., linarin, prep-HPLC, fraction ethyl acetate

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9940 Reliability Analysis of Soil Liquefaction Based on Standard Penetration: A Case Study in Babol City

Authors: Mehran Naghizaderokni, Asscar Janalizadechobbasty

Abstract:

There are more probabilistic and deterministic liquefaction evaluation procedures in order to judge whether liquefaction will occur or not. A review of this approach reveals that there is a need for a comprehensive procedure that accounts for different sources of uncertainty in liquefaction evaluation. In fact, for the same set of input parameters, different methods provide different factors of safety and/or probabilities of liquefaction. To account for the different uncertainties, including both the model and measurement uncertainties, reliability analysis is necessary. This paper has obtained information from Standard Penetration Test (SPT) and some empirical approaches such as: Seed et al, Highway bridge of Japan approach to soil liquefaction, The Overseas Coastal Area Development Institute of Japan (OCDI) and reliability method to studying potential of liquefaction in soil of Babol city in the north of Iran are compared. Evaluation potential of liquefaction in soil of Babol city is an important issue since the soil of some area contains sand, seismic area, increasing level of underground waters and consequently saturation of soil; therefore, one of the most important goals of this paper is to gain suitable recognition of liquefaction potential and find the most appropriate procedure of evaluation liquefaction potential to decrease related damages.

Keywords: reliability analysis, liquefaction, Babol, civil, construction and geological engineering

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9939 Evaluation of Settlement of Coastal Embankments Using Finite Elements Method

Authors: Sina Fadaie, Seyed Abolhassan Naeini

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Coastal embankments play an important role in coastal structures by reducing the effect of the wave forces and controlling the movement of sediments. Many coastal areas are underlain by weak and compressible soils. Estimation of during construction settlement of coastal embankments is highly important in design and safety control of embankments and appurtenant structures. Accordingly, selecting and establishing of an appropriate model with a reasonable level of complication is one of the challenges for engineers. Although there are advanced models in the literature regarding design of embankments, there is not enough information on the prediction of their associated settlement, particularly in coastal areas having considerable soft soils. Marine engineering study in Iran is important due to the existence of two important coastal areas located in the northern and southern parts of the country. In the present study, the validity of Terzaghi’s consolidation theory has been investigated. In addition, the settlement of these coastal embankments during construction is predicted by using special methods in PLAXIS software by the help of appropriate boundary conditions and soil layers. The results indicate that, for the existing soil condition at the site, some parameters are important to be considered in analysis. Consequently, a model is introduced to estimate the settlement of the embankments in such geotechnical conditions.

Keywords: consolidation, settlement, coastal embankments, numerical methods, finite elements method

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9938 Development of a Mixed-Reality Hands-Free Teleoperated Robotic Arm for Construction Applications

Authors: Damith Tennakoon, Mojgan Jadidi, Seyedreza Razavialavi

Abstract:

With recent advancements of automation in robotics, from self-driving cars to autonomous 4-legged quadrupeds, one industry that has been stagnant is the construction industry. The methodologies used in a modern-day construction site consist of arduous physical labor and the use of heavy machinery, which has not changed over the past few decades. The dangers of a modern-day construction site affect the health and safety of the workers due to performing tasks such as lifting and moving heavy objects and having to maintain unhealthy posture to complete repetitive tasks such as painting, installing drywall, and laying bricks. Further, training for heavy machinery is costly and requires a lot of time due to their complex control inputs. The main focus of this research is using immersive wearable technology and robotic arms to perform the complex and intricate skills of modern-day construction workers while alleviating the physical labor requirements to perform their day-to-day tasks. The methodology consists of mounting a stereo vision camera, the ZED Mini by Stereolabs, onto the end effector of an industrial grade robotic arm, streaming the video feed into the Virtual Reality (VR) Meta Quest 2 (Quest 2) head-mounted display (HMD). Due to the nature of stereo vision, and the similar field-of-views between the stereo camera and the Quest 2, human-vision can be replicated on the HMD. The main advantage this type of camera provides over a traditional monocular camera is it gives the user wearing the HMD a sense of the depth of the camera scene, specifically, a first-person view of the robotic arm’s end effector. Utilizing the built-in cameras of the Quest 2 HMD, open-source hand-tracking libraries from OpenXR can be implemented to track the user’s hands in real-time. A mixed-reality (XR) Unity application can be developed to localize the operator's physical hand motions with the end-effector of the robotic arm. Implementing gesture controls will enable the user to move the robotic arm and control its end-effector by moving the operator’s arm and providing gesture inputs from a distant location. Given that the end effector of the robotic arm is a gripper tool, gripping and opening the operator’s hand will translate to the gripper of the robot arm grabbing or releasing an object. This human-robot interaction approach provides many benefits within the construction industry. First, the operator’s safety will be increased substantially as they can be away from the site-location while still being able perform complex tasks such as moving heavy objects from place to place or performing repetitive tasks such as painting walls and laying bricks. The immersive interface enables precision robotic arm control and requires minimal training and knowledge of robotic arm manipulation, which lowers the cost for operator training. This human-robot interface can be extended to many applications, such as handling nuclear accident/waste cleanup, underwater repairs, deep space missions, and manufacturing and fabrication within factories. Further, the robotic arm can be mounted onto existing mobile robots to provide access to hazardous environments, including power plants, burning buildings, and high-altitude repair sites.

Keywords: construction automation, human-robot interaction, hand-tracking, mixed reality

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9937 Application and Regeneration of CuMnCeO Catalyst Supporting K₂CO₃ Sorbent Adapted to CO Oxidation and CO₂ Absorption

Authors: Jin Lin, Shouxiang Lu, Kim Meow Liew

Abstract:

The requirement for the long-term mission of the submarine and spacecraft has made the removal of CO₂ and trace CO the critical technology to ensure the health and life of the crews. In this work, CuMnCe, a metal oxide catalyst, supporting K₂CO₃ sorbent was prepared by the wet-solid state impregnation method to realize the integrated CO and CO₂ removal, which might also reduce the volume/mass load of the purification units in the limited space. The as-prepared samples with different addition amount of K₂CO₃ were tested using the fixed bed reactor to reveal the CO oxidation and CO₂ absorption behavior. And the regeneration and stability experiments were also conducted. The results showed that the samples realized the catalyst and sorbent integration to capture CO and CO₂ at the same time. The addition amount of the sorbent had a weak influence on the CO oxidation performance. While the addition amount affected the CO₂ sorption efficiency and capacity significantly. Meanwhile, the presence of water vapor could reduce the CO oxidation activity of the samples similarly, whether with K2CO3 sorbent addition or not. Furtherly, regeneration and stability experiment results showed that the samples after 3-5 times regeneration exhibited almost the same performance of CO and CO₂ removal. Summarily, CuMnCe catalyst supporting K₂CO₃ sorbent could be a good attempt to control CO and CO₂ pollutants generated from the daily equipment running and staff breathing in the confined space such as submarine and spacecraft.

Keywords: CO oxidation, CO₂ absorptio, potassium carbonate, CuMnCe metal oxide, confined space

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9936 Key Success Factors for Malaysian SMES Companies’ Entrepreneurial Leader

Authors: Zainal Abu Zarim, Hafizah Omar Zaki

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The objective of this study is to analyse the success factors of entrepreneurs in the Malaysian SMEs in the urge to discover their entrepreneurial leadership characteristics. Data has been collected from top 50 SME award winning companies. The study has used the qualitative approach to data collection, where interviews are dispersed on these selected companies. From these 50 SMEs, only 25 accepted the interview request where one entrepreneur from each SME answered the questions. To successfully run this study, we administered some questions based on Hornaday 42 characteristics of an entrepreneurs, as well some structured questions to determine a successful of a company. The result shows that, entrepreneurs are confident, determine, diligent, flexible, responsive to challenges, responsible, foresight, courageous, aggressive, and committed. Consistent to this, several elements that makes the company successful includes (1) strong financial control, (2) continuous improvement, (3) product quality and product safety as top priority, (4) hard work and team work, and (5) eagerness in taking challenges. These results has deemed that entrepreneurs in many aspects are also leaders that are risk averse and determine, and are eager to work on continuous improvement in a financially strong company.

Keywords: characteristics of entrepreneurs, success of a company, key success factors, Malaysian SMEs

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9935 Mesocarbon Microbeads Modification of Stainless-Steel Current Collector to Stabilize Lithium Deposition and Improve the Electrochemical Performance of Anode Solid-State Lithium Hybrid Battery

Authors: Abebe Taye

Abstract:

The interest in enhancing the performance of all-solid-state batteries featuring lithium metal anodes as a potential alternative to traditional lithium-ion batteries has prompted exploration into new avenues. A promising strategy involves transforming lithium-ion batteries into hybrid configurations by integrating lithium-ion and lithium-metal solid-state components. This study is focused on achieving stable lithium deposition and advancing the electrochemical capabilities of solid-state lithium hybrid batteries with anodes by incorporating mesocarbon microbeads (MCMBs) blended with silver nanoparticles. To achieve this, mesocarbon microbeads (MCMBs) blended with silver nanoparticles are coated on stainless-steel current collectors. These samples undergo a battery of analyses employing diverse techniques. Surface morphology is studied through scanning electron microscopy (SEM). The electrochemical behavior of the coated samples is evaluated in both half-cell and full-cell setups utilizing an argyrodite-type sulfide electrolyte. The stability of MCMBs in the electrolyte is assessed using electrochemical impedance spectroscopy (EIS). Additional insights into the composition are gleaned through X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and energy-dispersive X-ray spectroscopy (EDS). At an ultra-low N/P ratio of 0.26, stability is upheld for over 100 charge/discharge cycles in half-cells. When applied in a full-cell configuration, the hybrid anode preserves 60.1% of its capacity after 80 cycles at 0.3 C under a low N/P ratio of 0.45. In sharp contrast, the capacity retention of the cell using untreated MCMBs declines to 20.2% after a mere 60 cycles. The introduction of mesocarbon microbeads (MCMBs) combined with silver nanoparticles into the hybrid anode of solid-state lithium batteries substantially elevates their stability and electrochemical performance. This approach ensures consistent lithium deposition and removal, mitigating dendrite growth and the accumulation of inactive lithium. The findings from this investigation hold significant value in elevating the reversibility and energy density of lithium-ion batteries, thereby making noteworthy contributions to the advancement of more efficient energy storage systems.

Keywords: MCMB, lithium metal, hybrid anode, silver nanoparticle, cycling stability

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9934 A Sociolinguistic Investigation of Code-Switching Practices of ESL Students Outside EFL Classrooms

Authors: Shehroz Mukhtar, Maqsood Ahmed, Abdullah Mukhtar, Choudhry Shahid, Waqar Javaid

Abstract:

Code switching is a common phenomenon, generally observed in multilingual communities across the globe. A critical look at code switching literature reveals that mostly code switching has been studied in classroom in learning and teaching context while code switching outside classroom in settings such as café, hostel and so on have been the least explored areas. Current research investigated the reasons for code switching in the interactive practices of students and their perceptions regarding the same outside the classroom settings. This paper is the study of the common practice that prevails in the Universities of Sialkot that bilinguals mix two languages when they speak in different class room situations. In Pakistani classrooms where Multilingual are in abundance i.e. they can speak two or more than two languages at the same time, the code switching or language combination is very common. The teachers of Sialkot switch from one language to another consciously or unconsciously while teaching English in the class rooms. This phenomenon has not been explored in the Sialkot’s teaching context. In Sialkot private educational institutes does not encourage code-switching whereas the public or government institutes use it frequently. The crux of this research is to investigate and identify the importance of code switching by taking its users in consideration. Survey research method and survey questionnaire will be used to get exact data from teachers and students. We will try to highlight the functions and importance of code switching in foreign language classrooms of Sialkot and will explore why this trend is emerging in Sialkot.

Keywords: code switching, bilingual context, L1, L2

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9933 Bayesian Inference for High Dimensional Dynamic Spatio-Temporal Models

Authors: Sofia M. Karadimitriou, Kostas Triantafyllopoulos, Timothy Heaton

Abstract:

Reduced dimension Dynamic Spatio-Temporal Models (DSTMs) jointly describe the spatial and temporal evolution of a function observed subject to noise. A basic state space model is adopted for the discrete temporal variation, while a continuous autoregressive structure describes the continuous spatial evolution. Application of such a DSTM relies upon the pre-selection of a suitable reduced set of basic functions and this can present a challenge in practice. In this talk, we propose an online estimation method for high dimensional spatio-temporal data based upon DSTM and we attempt to resolve this issue by allowing the basis to adapt to the observed data. Specifically, we present a wavelet decomposition in order to obtain a parsimonious approximation of the spatial continuous process. This parsimony can be achieved by placing a Laplace prior distribution on the wavelet coefficients. The aim of using the Laplace prior, is to filter wavelet coefficients with low contribution, and thus achieve the dimension reduction with significant computation savings. We then propose a Hierarchical Bayesian State Space model, for the estimation of which we offer an appropriate particle filter algorithm. The proposed methodology is illustrated using real environmental data.

Keywords: multidimensional Laplace prior, particle filtering, spatio-temporal modelling, wavelets

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9932 A Non-Destructive Estimation Method for Internal Time in Perilla Leaf Using Hyperspectral Data

Authors: Shogo Nagano, Yusuke Tanigaki, Hirokazu Fukuda

Abstract:

Vegetables harvested early in the morning or late in the afternoon are valued in plant production, and so the time of harvest is important. The biological functions known as circadian clocks have a significant effect on this harvest timing. The purpose of this study was to non-destructively estimate the circadian clock and so construct a method for determining a suitable harvest time. We took eight samples of green busil (Perilla frutescens var. crispa) every 4 hours, six times for 1 day and analyzed all samples at the same time. A hyperspectral camera was used to collect spectrum intensities at 141 different wavelengths (350–1050 nm). Calculation of correlations between spectrum intensity of each wavelength and harvest time suggested the suitability of the hyperspectral camera for non-destructive estimation. However, even the highest correlated wavelength had a weak correlation, so we used machine learning to raise the accuracy of estimation and constructed a machine learning model to estimate the internal time of the circadian clock. Artificial neural networks (ANN) were used for machine learning because this is an effective analysis method for large amounts of data. Using the estimation model resulted in an error between estimated and real times of 3 min. The estimations were made in less than 2 hours. Thus, we successfully demonstrated this method of non-destructively estimating internal time.

Keywords: artificial neural network (ANN), circadian clock, green busil, hyperspectral camera, non-destructive evaluation

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9931 Calcium Uptake and Yield of Pleurotus ostreatus Cultivated in Rice Straw-Based Substrate Enriched with Natural Sources

Authors: Arianne V. Julian, Michael R. Umagat, Renato G. Reyes

Abstract:

Pleurotus ostreatus, which is one of the most widely cultivated mushrooms, is an excellent source of protein and other minerals but inherently contains low calcium level. Calcium plays several vital functions in human health; therefore, adequate daily intake is necessary. Supplementation of growth substrate is a significant approach in mushroom production to improve nutritional content and yield. This study focused on the influence of varying concentrations of Ca supplementation derived from natural sources including agricultural lime, eggshell and oyster shell in rice straw-based formulation for the production of P. ostreatus. The effect of Ca supplementation on the total yield and Ca content were obtained. Results revealed that these natural sources increased both the yield and Ca of P. ostreatus. Mushroom grown in substrate with 8-10% agricultural lime and 6% eggshell powder produced the highest yields while using oyster shell powder did not vary with the control. Meanwhile, substrate supplementation using agricultural lime and eggshell powder in all concentrations have increased Ca in fruiting bodies. However, Ca was not absorbed in the oyster shell powder-supplemented substrate. These findings imply the potential of agricultural lime and eggshell powder in the production of Ca-enriched mushrooms resulting in higher yield.

Keywords: calcium fortification, mushroom production, natural sources, Pleurotus ostreatus

Procedia PDF Downloads 172
9930 Study of the Late Phase of Core Degradation during Reflooding by Safety Injection System for VVER1000 with ASTECv2 Computer Code

Authors: Antoaneta Stefanova, Rositsa Gencheva, Pavlin Groudev

Abstract:

This paper presents the modeling approach in SBO sequence for VVER 1000 reactors and describes the reactor core behavior at late in-vessel phase in case of late reflooding by HPIS and gives preliminary results for the ASTECv2 validation. The work is focused on investigation of plant behavior during total loss of power and the operator actions. The main goal of these analyses is to assess the phenomena arising during the Station blackout (SBO) followed by primary side high pressure injection system (HPIS) reflooding of already damaged reactor core at very late ‘in-vessel’ phase. The purpose of the analysis is to define how the later HPIS switching on can delay the time of vessel failure or possibly avoid vessel failure. For this purpose has been simulated an SBO scenario with injection of cold water by a high pressure pump (HPP) in cold leg at different stages of core degradation. The times for HPP injection were chosen based on previously performed investigations.

Keywords: VVER, operator action validation, reflooding of overheated reactor core, ASTEC computer code

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9929 Effects of Some Factors Affecting Optimum Reproductive Capacity of Local Breeds of Sheep in Nigeria

Authors: D. Zahraddeen, N. M. Lemu, P. P. Barje, I. S. R. Butswat

Abstract:

This study was conducted to investigate some of the factors affecting the optimum reproductive capacity of the indigenous breeds of sheep in Nigeria. A total of 767 sheep of different breeds were investigated. The reproductive indices considered were birth/weaning weights, litter size, parity, mortality, reproductive problems/disorders, body condition score (BCS), as well as growth traits. The results showed that litter size, parity, and BCS had significant (p < 0.05) effects on birth/weaning weights, mortality rates and growth traits of the sheep breeds studied. Similarly, the rearing method/system significantly (p < 0.05) influenced other reproductive traits such as birth/weaning weights, mortality, growth performance of lambs. However, the major reproductive problems/disorders in the ewes were dystocia (30.94%), retained placenta (16.91%), mastitis (15.83), pregnancy toxaemia (11.51%), uterine prolapse (6.48%) and vaginal prolapse (3.24%). In the rams, the incidence of reproductive problems included cryptorchidism (1.08%), orchitis (2.87%) and scrotal dermatophilosis (1.79%), among others. This study concludes that the four breeds of sheep (Balami, Yankasa, Uda, and West African Dwarf sheep) and their crosses exhibited varied genetic make-up and potentials. However, the large number of sheep farmers practicing the extensive production system might be responsible for the low reproductive performance of this species in the country. It is, therefore, recommended that significant improvement could be achieved through enhanced management practices of these animals.

Keywords: sheep, breeds, reproduction, disorders

Procedia PDF Downloads 143
9928 Design, Fabrication, and Study of Droplet Tube Based Triboelectric Nanogenerators

Authors: Yana Xiao

Abstract:

The invention of Triboelectric Nanogenerators (TENGs) provides an effective approach to the sustainable power of energy. Liquid-solid interfaces-based TENGs have been researched in virtue of less friction for harvesting energy from raindrops, rivers, and oceans in the form of water flows. However, TENGs based on droplets have rarely been investigated. In this study, we have proposed a new kind of droplet tube-based TENG (DT-TENG) with free-standing and reformative grating electrodes. Both straight and curved DT-TENGs were designed, fabricated, and evaluated, including straight tubes TENG with 27 electrodes and curved tubes TENG of 25cm radius curvature- at the inclination of 30°, 45° and 60° respectively. Different materials and hydrophobicity treatments for the tubes have also been studied, together with a discussion on the mechanism and applications of DT-TENGs. As different types of liquid discrepant energy performance, this kind of DT-TENG can be potentially used in laboratories to identify liquid or solvent. In addition, a smart fishing float is contrived, which can recognize different levels of movement speeds brought about by different weights and generate corresponding electric signals to remind the angler. The electric generation performance when using a PVC helix tube around a cylinder is similar in straight situations under the inclination of 45° in this experiment. This new structure changes the direction of a water drop or flows without losing kinetic energy, which makes utilizing Helix-Tube-TENG to harvest energy from different building morphologies possible.

Keywords: triboelectric nanogenerator, energy harvest, liquid tribomaterial, structure innovation

Procedia PDF Downloads 74
9927 Study of the Mega–Landslide at the Community of Ropoto, Central Greece, and of the Design of Mitigation and Early Warning System Using the Fiber Bragg Grating Technology

Authors: Michael Bellas, George Voulgaridis

Abstract:

This paper refers to the world known mega - landslide induced at the community of Ropoto, belonging to the Municipality of Trikala, in the Central part of Greece. The landslide affected the debris as well as the colluvium mantle of the flysch, and makes up a special case of study in engineering geology and geotechnical engineering not only because of the size of the domain affected by the landslide (approximately 750m long), but also because of the geostructure’s global behavior. Due to the landslide, the whole community’s infrastructure massively collapsed and human lives were put in danger. After the complete simulation of the coupled Seepage - Deformation phenomenon due to the extreme rainfall, and by closely examining the slope’s global behavior, both the mitigation of the landslide, as well as, an advanced surveillance method (Fiber Bragg Grating) using fiber optics were further studied, in order both to retain the geostructure and to monitor its health by creating an early warning system, which would serve as a complete safety net for saving both the community’s infrastructure as well as the lives of its habitats.

Keywords: landslide, remediation measures, the finite element method (FEM), Fiber Bragg Grating (FBG) sensing method

Procedia PDF Downloads 314