Search results for: critical parameters
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 13250

Search results for: critical parameters

11720 Effect of Dietary Sour Lemon Peel Essential Oil on Serum Parameters in Rainbow Trout (Oncorhynchus mykiss) Fingerlings against Deltamethrin Stress

Authors: Maryam Amiri Resketi, Sakineh Yeganeh, Khosro Jani Khalili

Abstract:

The aim of this study was to investigate the effect of dietary lemon peel essential oil (Citrus limon) on serum parameters and liver enzyme activity of rainbow trout (Oncorhynchus mykiss) was exposed to deltamethrin. The 96-hour lethal concentrations of the toxin on rainbow trout (Oncorhynchus mykiss), was determined according to standard procedures O.E.C.D in static (Static). 96-hour LC50 was obtained 0.0082 mg/l by using statistical methods Probit program version. The maximum allowable concentration of deltamethrin was calculated 0.00082 mg/l in natural environment and was used for this experiment. Eight treatments were designed based on 3 levels of lemon essential oil 200, 400 and 600 mg/kg and 2 levels of deltamethrin 0 and 0.00082. Rainbow trout with an average weight of 95.14 ± 3.8 g were distributed in 300-liter tanks and cultured for eight weeks. Fish were fed in an amount of 2% of body weight. Water changes were done on a daily basis (90 percent of the tank). About the tanks containing 10 % deltamethrin, after dewatering, suitable concentration of toxin was added to water. At the end of the test, serum biochemical parameters (total protein, albumin, glucose, cholesterol, and triglycerides) and liver enzymes (ALP, AST, ALT and LDH) were evaluated. In treatments without and with toxin, increasing 400 mg/kg oil increased total protein and albumin levels and lower cholesterol and triglycerides were observed (p < 0.05). Rise to the level of 400 mg/kg of lemon peel essential oil treatments contain pesticides, reduced the amount of enzymes ALP, ALT and LDH compared to treatment of toxin-free lemon peel essential oil (p < 0.05). The results showed that usage of lemon peel essential oil in fish diet can increase the immune system parameters and strengthen it with strong antioxidant activity followed by reducing the effect of deltamethrin on the immune system of fish and effective dose can prevent the adverse effects of toxin due to the weakening of the fish immune system at the time of toxic pollutant entrance in fish farms.

Keywords: deltamethrin, Oncorhynchus mykiss, LC5096h, lemon peel (citrus limon) essential oil, serum parameters, liver enzymes

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11719 Localized Analysis of Cellulosic Fibrous Insulation Materials

Authors: Chady El Hachem, Pan Ye, Kamilia Abahri, Rachid Bennacer

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Considered as a building construction material, and regarding its environmental benefits, wood fiber insulation is the material of interest in this work. The definition of adequate elementary representative volume that guarantees reliable understanding of the hygrothermal macroscopic phenomena is very critical. At the microscopic scale, when subjected to hygric solicitations, fibers undergo local dimensionless variations. It is therefore necessary to master this behavior, which affects the global response of the material. This study consists of an experimental procedure using the non-destructive method, X-ray tomography, followed by morphological post-processing analysis using ImageJ software. A refine investigation took place in order to identify the representative elementary volume and the sufficient resolution for accurate structural analysis. The second part of this work was to evaluate the microscopic hygric behavior of the studied material. Many parameters were taken into consideration, like the evolution of the fiber diameters, distribution along the sorption cycle and the porosity, and the water content evolution. In addition, heat transfer simulations based on the energy equation resolution were achieved on the real structure. Further, the problematic of representative elementary volume was elaborated for such heterogeneous material. Moreover, the material’s porosity and its fibers’ thicknesses show very big correlation with the water content. These results provide the literature with very good understanding of wood fiber insulation’s behavior.

Keywords: hygric behavior, morphological characterization, wood fiber insulation material, x-ray tomography

Procedia PDF Downloads 252
11718 A Hybrid Genetic Algorithm and Neural Network for Wind Profile Estimation

Authors: M. Saiful Islam, M. Mohandes, S. Rehman, S. Badran

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Increasing necessity of wind power is directing us to have precise knowledge on wind resources. Methodical investigation of potential locations is required for wind power deployment. High penetration of wind energy to the grid is leading multi megawatt installations with huge investment cost. This fact appeals to determine appropriate places for wind farm operation. For accurate assessment, detailed examination of wind speed profile, relative humidity, temperature and other geological or atmospheric parameters are required. Among all of these uncertainty factors influencing wind power estimation, vertical extrapolation of wind speed is perhaps the most difficult and critical one. Different approaches have been used for the extrapolation of wind speed to hub height which are mainly based on Log law, Power law and various modifications of the two. This paper proposes a Artificial Neural Network (ANN) and Genetic Algorithm (GA) based hybrid model, namely GA-NN for vertical extrapolation of wind speed. This model is very simple in a sense that it does not require any parametric estimations like wind shear coefficient, roughness length or atmospheric stability and also reliable compared to other methods. This model uses available measured wind speeds at 10m, 20m and 30m heights to estimate wind speeds up to 100m. A good comparison is found between measured and estimated wind speeds at 30m and 40m with approximately 3% mean absolute percentage error. Comparisons with ANN and power law, further prove the feasibility of the proposed method.

Keywords: wind profile, vertical extrapolation of wind, genetic algorithm, artificial neural network, hybrid machine learning

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11717 Geographic Legacies for Modern Day Disease Research: Autism Spectrum Disorder as a Case-Control Study

Authors: Rebecca Richards Steed, James Van Derslice, Ken Smith, Richard Medina, Amanda Bakian

Abstract:

Elucidating gene-environment interactions for heritable disease outcomes is an emerging area of disease research, with genetic studies informing hypotheses for environment and gene interactions underlying some of the most confounding diseases of our time, like autism spectrum disorder (ASD). Geography has thus far played a key role in identifying environmental factors contributing to disease, but its use can be broadened to include genetic and environmental factors that have a synergistic effect on disease. Through the use of family pedigrees and disease outcomes with life-course residential histories, space-time clustering of generations at critical developmental windows can provide further understanding of (1) environmental factors that contribute to disease patterns in families, (2) susceptible critical windows of development most impacted by environment, (3) and that are most likely to lead to an ASD diagnosis. This paper introduces a retrospective case-control study that utilizes pedigree data, health data, and residential life-course location points to find space-time clustering of ancestors with a grandchild/child with a clinical diagnosis of ASD. Finding space-time clusters of ancestors at critical developmental windows serves as a proxy for shared environmental exposures. The authors refer to geographic life-course exposures as geographic legacies. Identifying space-time clusters of ancestors creates a bridge for researching exposures of past generations that may impact modern-day progeny health. Results from the space-time cluster analysis show multiple clusters for the maternal and paternal pedigrees. The paternal grandparent pedigree resulted in the most space-time clustering for birth and childhood developmental windows. No statistically significant clustering was found for adolescent years. These results will be further studied to identify the specific share of space-time environmental exposures. In conclusion, this study has found significant space-time clusters of parents, and grandparents for both maternal and paternal lineage. These results will be used to identify what environmental exposures have been shared with family members at critical developmental windows of time, and additional analysis will be applied.

Keywords: family pedigree, environmental exposure, geographic legacy, medical geography, transgenerational inheritance

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11716 Critical Success Factors of OCOP Business Model in Pattani Province Thailand: A Qualitative Approach

Authors: Poonsook Thatchaopas, Nik Kamariah Nikmat, Nattakarn Eakuru

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Since 2003, the Thai Government has implemented several initiatives to encourage and incubate entrepreneurial skills and motivation among her citizens. One of the initiatives is the “One College One Product” business model or well known as ‘OCOP’, launched by the Vocational Education Commission to encourage partnership between college students to choose at least one product for business venture. In line with this mission, several business enterprises were established such as food products, restaurants, spa, Thai massage, minimart, computer maintenance, karaoke centre, internet café, mini theater etc. Currently, these business incubator projects can be observed at 404 vocational colleges and 21 incubation centres to encourage entrepreneurial small and medium enterprise (SME) development. However, the number of successful OCOP projects is still minimal. Out of the 404 individual OCOP projects at Vocational Colleges around Thailand, very few became successful. The objective of this paper is to identify the critical success factors needed to be a successful OCOP business entrepreneur. This study uses qualitative method by interviewing business partners of an OCOP business called Crispy Roti Krua Acheeva Brand (CRKAB). It is a snack food company that is developed at Pattani Vocational College in South Thailand. This project was initiated by three female entrepreneurs who were alumni student cum owners of the CRKAB. The finding shows that the main critical success factors are self-confidence, creativity or innovativeness, knowledge, skills and perseverance. Additionally, they reiterated that the keys to business success are product quality, perceived price, promotion, branding, new packaging to increase sales and continuous developments. The results implies for a student business SME to be successful, the company should have credible partners and effective marketing plan.

Keywords: student entrepreneurship, business incubator, food industry, qualitative, Thailand

Procedia PDF Downloads 379
11715 Kalman Filter Design in Structural Identification with Unknown Excitation

Authors: Z. Masoumi, B. Moaveni

Abstract:

This article is about first step of structural health monitoring by identifying structural system in the presence of unknown input. In the structural system identification, identification of structural parameters such as stiffness and damping are considered. In this study, the Kalman filter (KF) design for structural systems with unknown excitation is expressed. External excitations, such as earthquakes, wind or any other forces are not measured or not available. The purpose of this filter is its strengths to estimate the state variables of the system in the presence of unknown input. Also least squares estimation (LSE) method with unknown input is studied. Estimates of parameters have been adopted. Finally, using two examples advantages and drawbacks of both methods are studied.

Keywords: Kalman filter (KF), least square estimation (LSE), structural health monitoring (SHM), structural system identification

Procedia PDF Downloads 301
11714 Characteristics of Speed Dispersion in Urban Expressway

Authors: Fujian Wang, Shubin Ruan, Meiwei Dai

Abstract:

Speed dispersion has tight relation to traffic safety. In this paper, several kinds of indicating parameters (the standard speed deviation, the coefficient of variation, the deviation of V85 and V15, the mean speed deviations, and the difference between adjacent car speeds) are applied to investigate the characteristics of speed dispersion, where V85 and V15 are 85th and 15th percentile speed, respectively. Their relationships are into full investigations and the results show that: there exists a positive relation (linear) between mean speed and the deviation of V85 and V15; while a negative relation (quadratic) between traffic flow and standard speed deviation. The mean speed deviation grows exponentially with mean speed while the absolute speed deviation between adjacent cars grows linearly with the headway. The results provide some basic information for traffic management.

Keywords: headway, indicating parameters, speed dispersion, urban expressway

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11713 Imipramine Ameliorate Altered Biochemical Parameter and Oxidative Damage in Depression

Authors: D. S. Mohale, A.V. Chandewar

Abstract:

Study was undertaken to investigate the effect of imipramine on various biochemical parameters and oxidative stress markers in short and long term depression on rats. Rats were subjected for short (21 days) and long term (84 days) social isolation for and checked for depression on force swim test and tail suspension method. Various markers of oxidative stress like lipid peroxidation (LPO), reduced glutathione (GSH), Supersoxide dismutase (SOD), catalase (CAT) and biochemical parameters like Serum glutamate oxaloacetate transaminase (SGOT), Serum glutamate pyruate transaminase (SGPT), and blood glucose were determined in depressed, control, imipramine and Vitamin E treated group. The rats displayed an increase in depression on force swim test and tail suspension method relative to control. There was significant increase in the level of LPO and decrease in the levels of GSH, SOD and CAT after short and long term depression. Increased oxidative stress in depression which may leads to alteration of biochemical parameters. Treatment with imipramine an tricyclic antidepressant significantly decreases in level of LPO, SGOT, SGPT and increase in the levels of GSH, SOD and CAT in long term depression.

Keywords: depression, oxidative stress, lipid peroxidation, reduced glutathione

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11712 A Study of the Trade-off Energy Consumption-Performance-Schedulability for DVFS Multicore Systems

Authors: Jalil Boudjadar

Abstract:

Dynamic Voltage and Frequency Scaling (DVFS) multicore platforms are promising execution platforms that enable high computational performance, less energy consumption and flexibility in scheduling the system processes. However, the resulting interleaving and memory interference together with per-core frequency tuning make real-time guarantees hard to be delivered. Besides, energy consumption represents a strong constraint for the deployment of such systems on energy-limited settings. Identifying the system configurations that would achieve a high performance and consume less energy while guaranteeing the system schedulability is a complex task in the design of modern embedded systems. This work studies the trade-off between energy consumption, cores utilization and memory bottleneck and their impact on the schedulability of DVFS multicore time-critical systems with a hierarchy of shared memories. We build a model-based framework using Parametrized Timed Automata of UPPAAL to analyze the mutual impact of performance, energy consumption and schedulability of DVFS multicore systems, and demonstrate the trade-off on an actual case study.

Keywords: time-critical systems, multicore systems, schedulability analysis, energy consumption, performance analysis

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11711 Mercury Removal Using Pseudomonas putida (ATTC 49128): Effect of Acclimatization Time, Speed, and Temperature of Incubator Shaker

Authors: A. A. M. Azoddein, R. M. Yunus, N. M. Sulaiman, A. B. Bustary, K. Sabar

Abstract:

Microbes have been used to solve environmental problems for many years. The use microorganism to sequester, precipitate or alter the oxidation state of various heavy metals has been extensively studied. Processes by which microorganism interacts with toxic metal are very diverse. The purpose of this research is to remove the mercury using Pseudomonas putida, pure culture ATTC 49128 at optimum growth parameters such as techniques of culture, acclimatization time and speed of incubator shaker. Thus, in this study, the optimum growth parameters of P.putida were obtained to achieve the maximum of mercury removal. Based on the optimum parameters of Pseudomonas putida for specific growth rate, the removal of two different mercury concentration, 1 ppm and 4 ppm were studied. A mercury-resistant bacterial strain which is able to reduce ionic mercury to metallic mercury was used to reduce ionic mercury from mercury nitrate solution. The overall levels of mercury removal in this study were between 80% and 90%. The information obtained in this study is of fundamental for understanding of the survival of P.putida ATTC 49128 in mercury solution. Thus, microbial mercury environmental pollutants removal is a potential biological treatment for waste water treatment especially in petrochemical industries in Malaysia.

Keywords: Pseudomonas putida, growth kinetic, biosorption, mercury, petrochemical waste water

Procedia PDF Downloads 651
11710 Monitoring the Thin Film Formation of Carrageenan and PNIPAm Microgels

Authors: Selim Kara, Ertan Arda, Fahrettin Dolastir, Önder Pekcan

Abstract:

Biomaterials and thin film coatings play a fundamental role in medical, food and pharmaceutical industries. Carrageenan is a linear sulfated polysaccharide extracted from algae and seaweeds. To date, such biomaterials have been used in many smart drug delivery systems due to their biocompatibility and antimicrobial activity properties. Poly (N-isopropylacrylamide) (PNIPAm) gels and copolymers have also been used in medical applications. PNIPAm shows lower critical solution temperature (LCST) property at about 32-34 °C which is very close to the human body temperature. Below and above the LCST point, PNIPAm gels exhibit distinct phase transitions between swollen and collapsed states. A special class of gels are microgels which can react to environmental changes significantly faster than microgels due to their small sizes. Quartz crystal microbalance (QCM) measurement technique is one of the attractive techniques which has been used for monitoring the thin-film formation process. A sensitive QCM system was designed as to detect 0.1 Hz difference in resonance frequency and 10-7 change in energy dissipation values, which are the measures of the deposited mass and the film rigidity, respectively. PNIPAm microgels with the diameter around few hundred nanometers in water were produced via precipitation polymerization process. 5 MHz quartz crystals with functionalized gold surfaces were used for the deposition of the carrageenan molecules and microgels in the solutions which were slowly pumped through a flow cell. Interactions between charged carrageenan and microgel particles were monitored during the formation of the film layers, and the Sauerbrey masses of the deposited films were calculated. The critical phase transition temperatures around the LCST were detected during the heating and cooling cycles. It was shown that it is possible to monitor the interactions between PNIPAm microgels and biopolymer molecules, and it is also possible to specify the critical phase transition temperatures by using a QCM system.

Keywords: carrageenan, phase transitions, PNIPAm microgels, quartz crystal microbalance (QCM)

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11709 Thermodynamic Analysis of an Ejector-Absorption Refrigeration Cycle with Using NH3-H2O

Authors: Samad Jafarmadar, Amin Habibzadeh, Mohammad Mehdi Rashidi, Sayed Sina Rezaei, Abbas Aghagoli

Abstract:

In this paper, the ejector-absorption refrigeration cycle is presented. This article deals with the thermodynamic simulation and the first and second law analysis of an ammonia-water. The effects of parameters such as condenser, absorber, generator, and evaporator temperatures have been investigated. The influence of the various operating parameters on the performance coefficient and exergy efficiency of this cycle has been studied. The results show that when the temperature of different parts increases, the performance coefficient and the exergy efficiency of the cycle decrease, except for evaporator and generator, that causes an increase in coefficient of performance (COP). According to the results, absorber and ejector have the highest exergy losses in the studied conditions.

Keywords: absorption refrigeration, COP, ejector, exergy efficiency

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11708 Friction Stir Welding Process as a Solid State Joining -A Review

Authors: Mohd Anees Siddiqui, S. A. H. Jafri, Shahnawaz Alam

Abstract:

Through this paper an attempt is made to review a special welding technology of friction stir welding (FSW) which is a solid-state joining. Friction stir welding is used for joining of two plates which are applied compressive force by using fixtures over the work table. This is a non consumable type welding technique in which a rotating tool of cylindrical shape is used. Process parameters such as tool geometry, joint design and process speed are discussed in the paper. Comparative study of Friction stir welding with other welding techniques such as MIG, TIG & GMAW is also done. Some light is put on several major applications of friction stir welding in different industries. Quality and environmental aspects of friction stir welding is also discussed.

Keywords: friction stir welding (FSW), process parameters, tool, solid state joining processes

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11707 Phase Segregating and Complex Forming Pb Based (=X-Pb) Liquid Alloys

Authors: Indra Bahadur Bhandari, Narayan Panthi, Ishwar Koirala, Devendra Adhikari

Abstract:

We have used a theoretical model based on the assumption of compound formation in binary alloys to study the thermodynamic, microscopic, and surface properties of Bi-Pb and In-Pb liquid alloys. A review of the phase diagrams for these alloys shows that one of the stable complexes for Bi-Pb liquid alloy is BiPb3; also, that InPb is a stable phase in liquid In-Pb alloys. Using the same interaction parameters that are fitted for the free energy of mixing, we have been able to compute the bulk and thermodynamic properties of the alloys. From our observations, we are able to show that the Bi-Pb liquid alloy exhibits compound formation over the whole concentration range and the In-Pb alloys undergo phase separation. With regards to surface properties, Pb segregates more to the surface in In-Pb alloys than in Bi-Pb alloys. The viscosity isotherms have a positive deviation from ideality for both Bi-Pb and In-Pb alloys.

Keywords: asymmetry, Bi-Pb, deviation, In-Pb, interaction parameters

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11706 Use of Treated Municipal Wastewater on Artichoke Crop

Authors: G. Disciglio, G. Gatta, A. Libutti, A. Tarantino, L. Frabboni, E. Tarantino

Abstract:

Results of a field study carried out at Trinitapoli (Puglia region, southern Italy) on the irrigation of an artichoke crop with three types of water (secondary-treated wastewater, SW; tertiary-treated wastewater, TW; and freshwater, FW) are reported. Physical, chemical and microbiological analyses were performed on the irrigation water, and on soil and yield samples. The levels of most of the chemical parameters, such as electrical conductivity, total suspended solids, Na+, Ca2+, Mg+2, K+, sodium adsorption ratio, chemical oxygen demand, biological oxygen demand over 5 days, NO3 –N, total N, CO32, HCO3, phenols and chlorides of the applied irrigation water were significantly higher in SW compared to GW and TW. No differences were found for Mg2+, PO4-P, K+ only between SW and TW. Although the chemical parameters of the three irrigation water sources were different, few effects on the soil were observed. Even though monitoring of Escherichia coli showed high SW levels, which were above the limits allowed under Italian law (DM 152/2006), contamination of the soil and the marketable yield were never observed. Moreover, no Salmonella spp. were detected in these irrigation waters; consequently, they were absent in the plants. Finally, the data on the quantitative-qualitative parameters of the artichoke yield with the various treatments show no significant differences between the three irrigation water sources. Therefore, if adequately treated, municipal wastewater can be used for irrigation and represents a sound alternative to conventional water resources.

Keywords: artichoke, soil chemical characteristics, fecal indicators, treated municipal wastewater, water recycling

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11705 Dynamic Investigation of Brake Squeal Problem in The Presence of Kinematic Nonlinearities

Authors: Shahroz Khan, Osman Taha Şen

Abstract:

In automotive brake systems, brake noise has been a major problem, and brake squeal is one of the critical ones which is an instability issue. The brake squeal produces an audible sound at high frequency that is irritating to the human ear. To study this critical problem, first a nonlinear mathematical model with three degree of freedom is developed. This model consists of a point mass that simulates the brake pad and a sliding surface that simulates the brake rotor. The model exposes kinematic and clearance nonlinearities, but no friction nonlinearity. In the formulation, the friction coefficient is assumed to be constant and the friction force does not change direction. The nonlinear governing equations of the model are first obtained, and numerical solutions are sought for different cases. Second, a computational model for the squeal problem is developed with a commercial software, and computational solutions are obtained with two different types of contact cases (solid-to-solid and sphere-to-plane). This model consists of three rigid bodies and several elastic elements that simulate the key characteristics of a brake system. The response obtained from this model is compared with numerical solutions in time and frequency domain.

Keywords: contact force, nonlinearities, brake squeal, vehicle brake

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11704 Community Strengths and Indigenous Resilience as Drivers for Health Reform Change

Authors: Shana Malio-Satele, Lemalu Silao Vaisola Sefo

Abstract:

Introductory Statement: South Seas Healthcare is Ōtara’s largest Pacific health provider in South Auckland, New Zealand. Our vision is excellent health and well-being for Pacific people and all communities through strong Pacific values. During the DELTA and Omicron outbreak of COVID-19, our Pacific people, indigenous Māori, and the community of South Auckland were disproportionately affected and faced significant hardship with existing inequities magnified. This study highlights the community-based learnings of harnessing community-based strengths such as indigenous resilience, family-informed experiences and stories that provide critical insights that inform health reform changes that will be sustainable and equitable for all indigenous populations. This study is based on critical learnings acquired during COVID-19 that challenge the deficit narrative common in healthcare about indigenous populations. This study shares case studies of marginalised groups and religious groups and the successful application of indigenous cultural strengths, such as collectivism, positive protective factors, and using trusted relationships to create meaningful change in the way healthcare is delivered. The significance of this study highlights the critical conditions needed to adopt a community-informed way of creating integrated healthcare that works and the role that the community can play in being part of the solution. Methodologies: Key methodologies utilised are indigenous and Pacific-informed. To achieve critical learnings from the community, Pacific research methodologies, heavily informed by the Polynesian practice, were applied. Specifically, this includes; Teu Le Va (Understanding the importance of trusted relationships as a way of creating positive health solutions); The Fonofale Methodology (A way of understanding how health incorporates culture, family, the physical, spiritual, mental and other dimensions of health, as well as time, context and environment; The Fonua Methodology – Understanding the overall wellbeing and health of communities, families and individuals and their holistic needs and environmental factors and the Talanoa methodology (Researching through conversation, where understanding the individual and community is through understanding their history and future through stories). Major Findings: Key findings in the study included: 1. The collectivist approach in the community is a strengths-based response specific to populations, which highlights the importance of trusted relationships and cultural values to achieve meaningful outcomes. 2. The development of a “village model” which identified critical components to achieving health reform change; system navigation, a sense of service that was culturally responsive, critical leadership roles, culturally appropriate support, and the ability to influence the system enablers to support an alternative way of working. Concluding Statement: There is a strong connection between community-based strengths being implemented into healthcare strategies and reforms and the sustainable success of indigenous populations and marginalised communities accessing services that are cohesive, equitably resourced, accessible and meaningful for families. This study highlights the successful community-informed approaches and practices used during the COVID-19 response in New Zealand that are now being implemented in the current health reform.

Keywords: indigenous voice, community voice, health reform, New Zealand

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11703 Geometrically Linear Symmetric Free Vibration Analysis of Sandwich Beam

Authors: Ibnorachid Zakaria, El Bikri Khalid, Benamar Rhali, Farah Abdoun

Abstract:

The aim of the present work is to study the linear free symmetric vibration of three-layer sandwich beam using the energy method. The zigzag model is used to describe the displacement field. The theoretical model is based on the top and bottom layers behave like Euler-Bernoulli beams while the core layer like a Timoshenko beam. Based on Hamilton’s principle, the governing equation of motion sandwich beam is obtained in order to calculate the linear frequency parameters for a clamped-clamped and simple supported-simple-supported beams. The effects of material properties and geometric parameters on the natural frequencies are also investigated.

Keywords: linear vibration, sandwich, shear deformation, Timoshenko zig-zag model

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11702 Performance Evaluation of Iar Multi Crop Thresher

Authors: Idris Idris Sunusi, U.S. Muhammed, N.A. Sale, I.B. Dalha, N.A. Adam

Abstract:

Threshing efficiency and mechanical grain damages are among the important parameters used in rating the performance of agricultural threshers. To be acceptable to farmers, threshers should have high threshing efficiency and low grain. The objective of the research is to evaluate the performances of the thresher using sorghum and millet, the performances parameters considered are; threshing efficiency and mechanical grain damage. For millet, four drum speed levels; 700, 800, 900 and 1000 rpm were considered while for sorghum; 600, 700, 800 and 900 rpm were considered. The feed rate levels were 3, 4, 5 and 6 kg/min for both sorghum and millet; the levels of moisture content were 8.93 and 10.38% for sorghum and 9.21 and 10.81% for millet. For millet the test result showed a maximum of 98.37 threshing efficiencies and a minimum of 0.24% mechanical grain damage while for sorghum the test result indicated a maximum of 99.38 threshing efficiencies, and a minimum of 0.75% mechanical grain damage. In comparison to the previous thresher, the threshing efficiency and mechanical grain damage of the modified machine has improved by 2.01% and 330.56% for millet and 5.31%, 287.64% for sorghum. Also analysis of variance (ANOVA) showed that, the effect of drum speed, feed rate and moisture content were significant on the performance parameters.

Keywords: Threshing Efficiency, Mechanical Grain Damages, Sorghum and Millet, Multi Crop Thresher

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11701 Predatory Rule and the Rise of Military Coups: Insights From the 2020 Malian Case

Authors: Deretha Bester

Abstract:

This research employs a theoretical framework to investigate the interplay between factors that lead from predatory governance and predatory rule to military coups, utilizing the frustration-aggression theory as its guiding lens. It adopts a case-oriented approach and employs thematic analysis to examine the socio-economic, governance, and political environment that precipitated the August 2020 Malian military coup. Presenting seven key themes, it reveals how predatory rule and its manifestation in the Malian context was a critical factor in paving the way for the military coup. The study provides critical reflections into the historical, regional, and political dynamics reshaping Africa’s changing political landscape. It presents a conceptual model to comprehend how predatory governance fosters conditions favorable for military coups. Insights from the Malian case study offer valuable perspectives for analyzing events in comparable contexts. This understanding is crucial for grasping the precursors and impact of predatory rule and popular frustrations in contexts where military coups emerge.

Keywords: predatory rule, military coups, socio-political analysis, frustration-aggression theory, Mali

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11700 Multiple Relaxation Times in the Gibbs Ensemble Monte Carlo Simulation of Phase Separation

Authors: Bina Kumari, Subir K. Sarkar, Pradipta Bandyopadhyay

Abstract:

The autocorrelation function of the density fluctuation is studied in each of the two phases in a Gibbs Ensemble Monte Carlo (GEMC) simulation of the problem of phase separation for a square well potential with various values of its range. We find that the normalized autocorrelation function is described very well as a linear combination of an exponential function with a time scale τ₂ and a stretched exponential function with a time scale τ₁ and an exponent α. Dependence of (α, τ₁, τ₂) on the parameters of the GEMC algorithm and the range of the square well potential is investigated and interpreted. We also analyse the issue of how to choose the parameters of the GEMC simulation optimally.

Keywords: autocorrelation function, density fluctuation, GEMC, simulation

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11699 Enhancement in Digester Efficiency and Numerical Analysis for Optimal Design Parameters of Biogas Plant Using Design of Experiment Approach

Authors: Rajneesh, Priyanka Singh

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Biomass resources have been one of the main energy sources for mankind since the dawn of civilization. There is a vast scope to convert these energy sources into biogas which is a clean, low carbon technology for efficient management and conversion of fermentable organic wastes into a cheap and versatile fuel and bio/organic manure. Thus, in order to enhance the performance of anaerobic digester, an optimizing analysis of resultant parameters (organic dry matter (oDM) content, methane percentage, and biogas yield) has been done for a plug flow anaerobic digester having mesophilic conditions (20-40°C) with the wet fermentation process. Based on the analysis, correlations for oDM, methane percentage, and biogas yield are derived using multiple regression analysis. A statistical model is developed to correlate the operating variables using the design of experiment approach by selecting central composite design (CCD) of a response surface methodology. Results shown in the paper indicates that as the operating temperature increases the efficiency of digester gets improved provided that the pH and hydraulic retention time (HRT) remains constant. Working in an optimized range of carbon-nitrogen ratio for the plug flow digester, the output parameters show a positive change with the variation of dry matter content (DM).

Keywords: biogas, digester efficiency, design of experiment, plug flow digester

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11698 The Composer’s Hand: An Analysis of Arvo Pärt’s String Orchestral Work, Psalom

Authors: Mark K. Johnson

Abstract:

Arvo Pärt has composed over 80 text-based compositions based on nine different languages. But prior to 2015, it was not publicly known what texts the composer used in composing a number of his non-vocal works, nor the language of those texts. Because of this lack of information, few if any musical scholars have illustrated in any detail how textual structure applies to any of Pärt’s instrumental compositions. However, in early 2015, the Arvo Pärt Centre in Estonia published In Principio, a compendium of the texts Pärt has used to derive many of the parameters of his text-based compositions. This paper provides the first detailed analysis of the relationship between structural aspects of the Church Slavonic Eastern Orthodox text of Psalm 112 and the musical parameters that Pärt used when composing the string orchestral work Psalom. It demonstrates that Pärt’s text-based compositions are carefully crafted works, and that evidence of the presence of the ‘invisible’ hand of the composer can be found within every aspect of the underpinning structures, at the more elaborate middle ground level, and even within surface aspects of these works. Based on the analysis of Psalom, it is evident that the text Pärt selected for Psalom informed many of his decisions regarding the musical structures, parameters and processes that he deployed in composing this non-vocal text-based work. Many of these composerly decisions in relation to these various aspects cannot be fathomed without access to, and an understanding of, the text associated with the work.

Keywords: Arvo Pärt, minimalism, psalom, text-based process music

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11697 Impact of the Operation and Infrastructure Parameters to the Railway Track Capacity

Authors: Martin Kendra, Jaroslav Mašek, Juraj Čamaj, Matej Babin

Abstract:

The railway transport is considered as a one of the most environmentally friendly mode of transport. With future prediction of increasing of freight transport there are lines facing problems with demanded capacity. Increase of the track capacity could be achieved by infrastructure constructive adjustments. The contribution shows how the travel time can be minimized and the track capacity increased by changing some of the basic infrastructure and operation parameters, for example, the minimal curve radius of the track, the number of tracks, or the usable track length at stations. Calculation of the necessary parameter changes is based on the fundamental physical laws applied to the train movement, and calculation of the occupation time is dependent on the changes of controlling the traffic between the stations.

Keywords: curve radius, maximum curve speed, track mass capacity, reconstruction

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11696 Evaluation of Patients’ Quality of Life After Lumbar Disc Surgery and Movement Limitations

Authors: Shirin Jalili, Ramin Ghasemi

Abstract:

Lumbar microdiscectomy is the most commonly performed spinal surgery strategy; it is regularly performed to lighten the indications and signs of sciatica within the lower back and leg caused by a lumbar disc herniation. This surgery aims to progress leg pain, reestablish function, and enable a return to ordinary day-by-day exercises. Rates of lumbar disc surgery show critical geographic varieties recommending changing treatment criteria among working specialists. Few population-based considers have investigated the hazard of reoperation after disc surgery, and regional or inter specialty varieties within the reoperations are obscure. The conventional approach to recouping from lumbar microdiscectomy has been to restrain bending, lifting, or turning for a least 6 weeks in arrange to anticipate the disc from herniating once more. Traditionally, patients were exhorted to limit post-operative action, which was accepted to decrease the hazard of disc herniation and progressive insecurity. In modern hone, numerous specialists don't limit understanding of postoperative action due to the discernment this practice is pointless. There's a need of thinks about highlighting the result by distinctive scores or parameters after surgery for repetitive circle herniations of the lumbar spine at the starting herniation location. This study will evaluate the quality of life after surgical treatment of recurrent herniations with distinctive standardized approved result instruments.

Keywords: post-operative activity, disc, quality of life, treatment, movements

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11695 Analysis of Non-Conventional Roundabout Performance in Mixed Traffic Conditions

Authors: Guneet Saini, Shahrukh, Sunil Sharma

Abstract:

Traffic congestion is the most critical issue faced by those in the transportation profession today. Over the past few years, roundabouts have been recognized as a measure to promote efficiency at intersections globally. In developing countries like India, this type of intersection still faces a lot of issues, such as bottleneck situations, long queues and increased waiting times, due to increasing traffic which in turn affect the performance of the entire urban network. This research is a case study of a non-conventional roundabout, in terms of geometric design, in a small town in India. These types of roundabouts should be analyzed for their functionality in mixed traffic conditions, prevalent in many developing countries. Microscopic traffic simulation is an effective tool to analyze traffic conditions and estimate various measures of operational performance of intersections such as capacity, vehicle delay, queue length and Level of Service (LOS) of urban roadway network. This study involves analyzation of an unsymmetrical non-circular 6-legged roundabout known as “Kala Aam Chauraha” in a small town Bulandshahr in Uttar Pradesh, India using VISSIM simulation package which is the most widely used software for microscopic traffic simulation. For coding in VISSIM, data are collected from the site during morning and evening peak hours of a weekday and then analyzed for base model building. The model is calibrated on driving behavior and vehicle parameters and an optimal set of calibrated parameters is obtained followed by validation of the model to obtain the base model which can replicate the real field conditions. This calibrated and validated model is then used to analyze the prevailing operational traffic performance of the roundabout which is then compared with a proposed alternative to improve efficiency of roundabout network and to accommodate pedestrians in the geometry. The study results show that the alternative proposed is an advantage over the present roundabout as it considerably reduces congestion, vehicle delay and queue length and hence, successfully improves roundabout performance without compromising on pedestrian safety. The study proposes similar designs for modification of existing non-conventional roundabouts experiencing excessive delays and queues in order to improve their efficiency especially in the case of developing countries. From this study, it can be concluded that there is a need to improve the current geometry of such roundabouts to ensure better traffic performance and safety of drivers and pedestrians negotiating the intersection and hence this proposal may be considered as a best fit.

Keywords: operational performance, roundabout, simulation, VISSIM

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11694 A Comparative Case Study on the Relationship between Solar Energy Potential and Block Typology and Density in Shanghai Context

Authors: Dan Zhu, Jie Shi

Abstract:

This study explores the relationship between solar potential and block typology and density by analyzing sixteen existing typical street blocks with different topologies and densities in Shanghai, a representative high-density urban in China. Several indicators are proposed to quantify, and a methodology is conducted to evaluate and compare the solar potential both on façade and roof across various selected urban forms. 1) The importance of appropriate solar energy indicators and geometric parameters to be used in comparative studies, and 2) the relationship between urban typology, density, and solar performance are discussed. In this way, the results reveal the key design attributes contributing to increasing solar potential.

Keywords: block typology, geometric parameters, high-density urban, solar potential

Procedia PDF Downloads 322
11693 Determination of Safe Ore Extraction Methodology beneath Permanent Extraction in a Lead Zinc Mine with the Help of FLAC3D Numerical Model

Authors: Ayan Giri, Lukaranjan Phukan, Shantanu Karmakar

Abstract:

Structure and tectonics play a vital role in ore genesis and deposition. The existence of a swelling structure below the current level of a mine leads to the discovery of ores below some permeant developments of the mine. The discovery and the extraction of the ore body are very critical to sustain the business requirement of the mine. The challenge was to extract the ore without hampering the global stability of the mine. In order to do so, different mining options were considered and analysed by numerical modelling in FLAC3d software. The constitutive model prepared for this simulation is the improved unified constitutive model, which can better and more accurately predict the stress-strain relationships in a continuum model. The IUCM employs the Hoek-Brown criterion to determine the instantaneous Mohr-Coulomb parameters cohesion (c) and friction (ɸ) at each level of confining stress. The extra swelled part can be dimensioned as north-south strike width 50m, east-west strike width 50m. On the north side, already a stope (P1) is excavated of the dimension of 25m NS width. The different options considered were (a) Open stoping of extraction of southern part (P0) of 50m to the full extent, (b) Extraction of the southern part of 25m, then filling of both the primaries and extraction of secondary (S0) 25m in between. (c) Extraction of the southern part (P0) completely, preceded by backfill and modify the design of the secondary (S0) for the overall stability of the permanent excavation above the stoping.

Keywords: extraction, IUCM, FLAC 3D, stoping, tectonics

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11692 Stability Bound of Ruin Probability in a Reduced Two-Dimensional Risk Model

Authors: Zina Benouaret, Djamil Aissani

Abstract:

In this work, we introduce the qualitative and quantitative concept of the strong stability method in the risk process modeling two lines of business of the same insurance company or an insurance and re-insurance companies that divide between them both claims and premiums with a certain proportion. The approach proposed is based on the identification of the ruin probability associate to the model considered, with a stationary distribution of a Markov random process called a reversed process. Our objective, after clarifying the condition and the perturbation domain of parameters, is to obtain the stability inequality of the ruin probability which is applied to estimate the approximation error of a model with disturbance parameters by the considered model. In the stability bound obtained, all constants are explicitly written.

Keywords: Markov chain, risk models, ruin probabilities, strong stability analysis

Procedia PDF Downloads 238
11691 Comparative Evaluation of Pharmacologically Guided Approaches (PGA) to Determine Maximum Recommended Starting Dose (MRSD) of Monoclonal Antibodies for First Clinical Trial

Authors: Ibraheem Husain, Abul Kalam Najmi, Karishma Chester

Abstract:

First-in-human (FIH) studies are a critical step in clinical development of any molecule that has shown therapeutic promise in preclinical evaluations, since preclinical research and safety studies into clinical development is a crucial step for successful development of monoclonal antibodies for guidance in pharmaceutical industry for the treatment of human diseases. Therefore, comparison between USFDA and nine pharmacologically guided approaches (PGA) (simple allometry, maximum life span potential, brain weight, rule of exponent (ROE), two species methods and one species methods) were made to determine maximum recommended starting dose (MRSD) for first in human clinical trials using four drugs namely Denosumab, Bevacizumab, Anakinra and Omalizumab. In our study, the predicted pharmacokinetic (pk) parameters and the estimated first-in-human dose of antibodies were compared with the observed human values. The study indicated that the clearance and volume of distribution of antibodies can be predicted with reasonable accuracy in human and a good estimate of first human dose can be obtained from the predicted human clearance and volume of distribution. A pictorial method evaluation chart was also developed based on fold errors for simultaneous evaluation of various methods.

Keywords: clinical pharmacology (CPH), clinical research (CRE), clinical trials (CTR), maximum recommended starting dose (MRSD), clearance and volume of distribution

Procedia PDF Downloads 362