Search results for: load resistant factor design
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 19172

Search results for: load resistant factor design

6752 Parametrization of Piezoelectric Vibration Energy Harvesters for Low Power Embedded Systems

Authors: Yannick Verbelen, Tim Dekegel, Ann Peeters, Klara Stinders, Niek Blondeel, Sam De Winne, An Braeken, Abdellah Touhafi

Abstract:

Matching an embedded electronic application with a cantilever vibration energy harvester remains a difficult endeavour due to the large number of factors influencing the output power. In the presented work, complementary balanced energy harvester parametrization is used as a methodology for simplification of harvester integration in electronic applications. This is achieved by a dual approach consisting of an adaptation of the general parametrization methodology in conjunction with a straight forward harvester benchmarking strategy. For this purpose, the design and implementation of a suitable user friendly cantilever energy harvester benchmarking platform is discussed. Its effectiveness is demonstrated by applying the methodology to a commercially available Mide V21BL vibration energy harvester, with excitation amplitude and frequency as variables.

Keywords: vibration energy harvesting, piezoelectrics, harvester parametrization, complementary balanced energy harvesting

Procedia PDF Downloads 342
6751 Beliefs, Attitudes, and Understanding of Childhood Cancer Among White and Latino Parents in the Phoenix Metropolitan Area: A Comparative Study

Authors: Florence Awde

Abstract:

In 2023, it was expected 350 parents in Arizona would have a child receive a cancer diagnosis (Welcome Arizona Cancer Foundation For Children, n.d.). The news of a child’s diagnosis with cancer can be overwhelming and confusing, especially for those lucky enough to lack a personal tie to the disease that takes approximately 1800 children’s lives each year in the United States (Deegan et al., n.d.). A parent’s beliefs, attitudes, and understandings surrounding cancer are vital for medical staff to provide adequate and culturally competent care for each patient, especially across cultural and ethnic lines in regions housing multicultural populations. Arizona's cultural/linguistic mosaic houses many White and Latino populations and English and Spanish speakers. Variations in insurance coverage, from those insured through public insurance programs (e.g., Medicaid) or private insurance plans (e.g., employee-sponsored insurance) versus those uninsured, also factor into health-seeking attitudes and behaviors. To further understand parental attitudes, understandings, and beliefs towards childhood cancer, 22 parents (11 of Latino ethnicity, 11 of White ethnicity) were interviewed on these facets of childhood cancer, despite 21 of the 22 never having a child receive a cancer diagnosis. The exploration of these perceptions across ethnic lines revealed a higher report of fear-orientated beliefs amongst Latino parents--hypothesized to be rooted in the starkly contrasting lack of belief in the possibility of recovering for children with cancer, compared to their white counterparts who displayed more optimism in the recovery process. Further, this study’s results lay the foundation for future scholarship to explore avenues of information dispersal to Latino parents that correct misconceptions of health outcomes and enable earlier intervention to be possible, ultimately correlating to better health and treatment outcomes by increasing parental health literacy rates for childhood cancer in the Phoenix Metropolitan.

Keywords: Childhood Cancer, Parental Beliefs, Parental Attitudes, Parental Understandings, Phoenix Metropolitan, Culturally Competent Care, Health Disparities, Health Inequities

Procedia PDF Downloads 49
6750 Piled Critical Size Bone-Biomimetic and Biominerizable Nanocomposites: Formation of Bioreactor-Induced Stem Cell Gradients under Perfusion and Compression

Authors: W. Baumgartner, M. Welti, N. Hild, S. C. Hess, W. J. Stark, G. Meier Bürgisser, P. Giovanoli, J. Buschmann

Abstract:

Perfusion bioreactors are used to solve problems in tissue engineering in terms of sufficient nutrient and oxygen supply. Such problems especially occur in critical size grafts because vascularization is often too slow after implantation ending up in necrotic cores. Biominerizable and biocompatible nanocomposite materials are attractive and suitable scaffold materials for bone tissue engineering because they offer mineral components in organic carriers – mimicking natural bone tissue. In addition, human adipose derived stem cells (ASCs) can potentially be used to increase bone healing as they are capable of differentiating towards osteoblasts or endothelial cells among others. In the present study, electrospun nanocomposite disks of poly-lactic-co-glycolic acid and amorphous calcium phosphate nanoparticles (PLGA/a-CaP) were seeded with human ASCs and eight disks were stacked in a bioreactor running with normal culture medium (no differentiation supplements). Under continuous perfusion and uniaxial cyclic compression, load-displacement curves as a function of time were assessed. Stiffness and energy dissipation were recorded. Moreover, stem cell densities in the layers of the piled scaffold were determined as well as their morphologies and differentiation status (endothelial cell differentiation, chondrogenesis and osteogenesis). While the stiffness of the cell free constructs increased over time caused by the transformation of the a-CaP nanoparticles into flake-like apatite, ASC-seeded constructs showed a constant stiffness. Stem cell density gradients were histologically determined with a linear increase in the flow direction from the bottom to the top of the 3.5 mm high pile (r2 > 0.95). Cell morphology was influenced by the flow rate, with stem cells getting more roundish at higher flow rates. Less than 1 % osteogenesis was found upon osteopontin immunostaining at the end of the experiment (9 days), while no endothelial cell differentiation and no chondrogenesis was triggered under these conditions. All ASCs had mainly remained in their original pluripotent status within this time frame. In summary, we have fabricated a critical size bone graft based on a biominerizable bone-biomimetic nanocomposite with preserved stiffness when seeded with human ASCs. The special feature of this bone graft was that ASC densities inside the piled construct varied with a linear gradient, which is a good starting point for tissue engineering interfaces such as bone-cartilage where the bone tissue is cell rich while the cartilage exhibits low cell densities. As such, this tissue-engineered graft may act as a bone-cartilage interface after the corresponding differentiation of the ASCs.

Keywords: bioreactor, bone, cartilage, nanocomposite, stem cell gradient

Procedia PDF Downloads 294
6749 Assessing the Outcomes of Collaboration with Students on Curriculum Development and Design on an Undergraduate Art History Module

Authors: Helen Potkin

Abstract:

This paper presents a practice-based case study of a project in which the student group designed and planned the curriculum content, classroom activities and assessment briefs in collaboration with the tutor. It focuses on the co-creation of the curriculum within a history and theory module, Researching the Contemporary, which runs for BA (Hons) Fine Art and Art History and for BA (Hons) Art Design History Practice at Kingston University, London. The paper analyses the potential of collaborative approaches to engender students’ investment in their own learning and to encourage reflective and self-conscious understandings of themselves as learners. It also addresses some of the challenges of working in this way, attending to the risks involved and feelings of uncertainty produced in experimental, fluid and open situations of learning. Alongside this, it acknowledges the tensions inherent in adopting such practices within the framework of the institution and within the wider of context of the commodification of higher education in the United Kingdom. The concept underpinning the initiative was to test out co-creation as a creative process and to explore the possibilities of altering the traditional hierarchical relationship between teacher and student in a more active, participatory environment. In other words, the project asked about: what kind of learning could be imagined if we were all in it together? It considered co-creation as producing different ways of being, or becoming, as learners, involving us reconfiguring multiple relationships: to learning, to each other, to research, to the institution and to our emotions. The project provided the opportunity for students to bring their own research and wider interests into the classroom, take ownership of sessions, collaborate with each other and to define the criteria against which they would be assessed. Drawing on students’ reflections on their experience of co-creation alongside theoretical considerations engaging with the processual nature of learning, concepts of equality and the generative qualities of the interrelationships in the classroom, the paper suggests that the dynamic nature of collaborative and participatory modes of engagement have the potential to foster relevant and significant learning experiences. The findings as a result of the project could be quantified in terms of the high level of student engagement in the project, specifically investment in the assessment, alongside the ambition and high quality of the student work produced. However, reflection on the outcomes of the experiment prompts a further set of questions about the nature of positionality in connection to learning, the ways our identities as learners are formed in and through our relationships in the classroom and the potential and productive nature of creative practice in education. Overall, the paper interrogates questions of what it means to work with students to invent and assemble the curriculum and it assesses the benefits and challenges of co-creation. Underpinning it is the argument that, particularly in the current climate of higher education, it is increasingly important to ask what it means to teach and to envisage what kinds of learning can be possible.

Keywords: co-creation, collaboration, learning, participation, risk

Procedia PDF Downloads 109
6748 Adaptive Process Monitoring for Time-Varying Situations Using Statistical Learning Algorithms

Authors: Seulki Lee, Seoung Bum Kim

Abstract:

Statistical process control (SPC) is a practical and effective method for quality control. The most important and widely used technique in SPC is a control chart. The main goal of a control chart is to detect any assignable changes that affect the quality output. Most conventional control charts, such as Hotelling’s T2 charts, are commonly based on the assumption that the quality characteristics follow a multivariate normal distribution. However, in modern complicated manufacturing systems, appropriate control chart techniques that can efficiently handle the nonnormal processes are required. To overcome the shortcomings of conventional control charts for nonnormal processes, several methods have been proposed to combine statistical learning algorithms and multivariate control charts. Statistical learning-based control charts, such as support vector data description (SVDD)-based charts, k-nearest neighbors-based charts, have proven their improved performance in nonnormal situations compared to that of the T2 chart. Beside the nonnormal property, time-varying operations are also quite common in real manufacturing fields because of various factors such as product and set-point changes, seasonal variations, catalyst degradation, and sensor drifting. However, traditional control charts cannot accommodate future condition changes of the process because they are formulated based on the data information recorded in the early stage of the process. In the present paper, we propose a SVDD algorithm-based control chart, which is capable of adaptively monitoring time-varying and nonnormal processes. We reformulated the SVDD algorithm into a time-adaptive SVDD algorithm by adding a weighting factor that reflects time-varying situations. Moreover, we defined the updating region for the efficient model-updating structure of the control chart. The proposed control chart simultaneously allows efficient model updates and timely detection of out-of-control signals. The effectiveness and applicability of the proposed chart were demonstrated through experiments with the simulated data and the real data from the metal frame process in mobile device manufacturing.

Keywords: multivariate control chart, nonparametric method, support vector data description, time-varying process

Procedia PDF Downloads 286
6747 An Integrated Cognitive Performance Evaluation Framework for Urban Search and Rescue Applications

Authors: Antonio D. Lee, Steven X. Jiang

Abstract:

A variety of techniques and methods are available to evaluate cognitive performance in Urban Search and Rescue (USAR) applications. However, traditional cognitive performance evaluation techniques typically incorporate either the conscious or systematic aspect, failing to take into consideration the subconscious or intuitive aspect. This leads to incomplete measures and produces ineffective designs. In order to fill the gaps in past research, this study developed a theoretical framework to facilitate the integration of situation awareness (SA) and intuitive pattern recognition (IPR) to enhance the cognitive performance representation in USAR applications. This framework provides guidance to integrate both SA and IPR in order to evaluate the cognitive performance of the USAR responders. The application of this framework will help improve the system design.

Keywords: cognitive performance, intuitive pattern recognition, situation awareness, urban search and rescue

Procedia PDF Downloads 312
6746 Societal Acceptance of Trombe Wall in Buildings in Mediterranean Region: A Case Cyprus

Authors: Soad Abokhamis Mousavi

Abstract:

The Trombe wall is an ancient technique that continues to serve as an effective feature of a passive solar system. However, in practice, architects and their clients are not opting for the Trombe wall because of the view of the Trombe wall on the facades of the buildings. Therefore, this study has two main goals, and one of the goals is to find out why the Trombe wall is not considered in the buildings in the Mediterranean region. And the second goal is to find a solution to facilitate the societal acceptance of the Trombe walls in buildings. To cover the goals, the present work attempts to develop and design a different Trombe Wall with different Materials and views in the facades of the buildings. A qualitative data method was used in this article. The qualitative method was developed based on observation and questionnaires with different clients and expert architects in the selected region. Results indicate that the view of the Trombe wall in the facade of buildings can be used with different designs in order to not affect the beauty of the buildings.

Keywords: trombe wall, societal acceptance, building, energy efficacy

Procedia PDF Downloads 67
6745 Design, Spectroscopic, Structural Characterization, and Biological Studies for New Complexes via Charge Transfer Interaction of Ciprofloxacin Drug With π Acceptors

Authors: Khaled Alshammari

Abstract:

Ciprofloxacin (CIP) is a common antibiotic drug used as a strudy electron donor that interacts with dynamic π -acceptors such as 2,3-dinitrosalsylic acid (HDNS) and Tetracyanoethylene (TCNE) for synthesizing a new model of charge transfer (CT) complexes. The synthesized complexes were identified using diverse analytical methods such as UV–vis spectra, photometric titration measurements, FT-IR, HNMR Spectroscopy, and thermogravimetric analysis techniques (TGA/DTA). The stoichiometries for all the formed complexes were found to be a 1:1 M ratio between the reactants. The characteristic spectroscopic properties such as transition dipole moment (µ), oscillator strength (f), formation constant (KCT), ionization potential (ID), standard free energy (∆G), and energy of interaction (ECT) for the CT-complexes were collected. The developed CT complexes were tested for their toxicity on main organs, antimicrobial activity, antioxidant activity, and biofilm formation.

Keywords: biological, biofilm, toxicity, thermal analysis, charge transfer, spectroscopy

Procedia PDF Downloads 39
6744 Multiple-Channel Coulter Counter for Cell Sizing and Enumeration

Authors: Yu Chen, Seong-Jin Kim, Jaehoon Chung

Abstract:

High throughput cells counting and sizing are often required for biomedical applications. Here we report design, fabrication and validating of a micro-machined Coulter counter device with multiple-channel to realize such application for low cost. Multiple vertical through-holes were fabricated on a silicon chip, combined with the PDMS micro-fluidics channel that serves as the sensing channel. In order to avoid the crosstalk introduced by the electrical connection, instead of measuring the current passing through, the potential of each channel is monitored, thus the high throughput is possible. A peak of the output potential can be captured when the cell/particle is passing through the microhole. The device was validated by counting and sizing the polystyrene beads with diameter of 6 μm, 10 μm and 15 μm. With the sampling frequency to be set at 100 kHz, up to 5000 counts/sec for each channel can be realized. The counting and enumeration of MCF7 cancer cells are also demonstrated.

Keywords: Coulter counter, cell enumeration, high through-put, cell sizing

Procedia PDF Downloads 599
6743 Governance of Inter-Organizational Research Cooperation

Authors: Guenther Schuh, Sebastian Woelk

Abstract:

Companies face increasing challenges in research due to higher costs and risks. The intensifying technology complexity and interdisciplinarity require unique know-how. Therefore, companies need to decide whether research shall be conducted internally or externally with partners. On the other hand, research institutes meet increasing efforts to achieve good financing and to maintain high research reputation. Therefore, relevant research topics need to be identified and specialization of competency is necessary. However, additional competences for solving interdisciplinary research projects are also often required. Secured financing can be achieved by bonding industry partners as well as public fundings. The realization of faster and better research drives companies and research institutes to cooperate in organized research networks, which are managed by an administrative organization. For an effective and efficient cooperation, necessary processes, roles, tools and a set of rules need to be determined. The goal of this paper is to show the state-of-art research and to propose a governance framework for organized research networks.

Keywords: interorganizational cooperation, design of network governance, research network

Procedia PDF Downloads 353
6742 Perceptions on Community Media for Effective Acculturation in Nigerian Indigenous Languages

Authors: Chima Onwukwe

Abstract:

This study examined perceptions on the effectiveness, attendant challenges and remedies of community media for effective acculturation in Nigerian languages. The qualitative survey design was adopted with Focus Group Discussions (FGD) and Key Informant Interviews (KIIs) of 50 purposively chosen informants. It was perceived that community media could serve as veritable platform for effective acculturation in Nigerian languages since they would engender the setting of acculturation in Nigerian languages as national objective or goal. It was further held that the strengths of community media for acculturation were in being goal-defined, ensuring local content and diversification. The study identified that as palatable as the proposal for community media for effective acculturation in Nigerian languages is; it would be fraught with some set-backs or challenges that were very much surmountable. Perceptions pointed towards transient nature of community media and funding as challenges, as well as multi-based funding as one remedy. Immediate establishment of community media for the purpose of acculturation in Nigerian languages was recommended.

Keywords: perception, community media, acculturation, indigenous language

Procedia PDF Downloads 254
6741 Prevalence of Urinary Tract Infections and Risk Factors among Pregnant Women Attending Ante Natal Clinics in Government Primary Health Care Centres in Akure

Authors: Adepeju Simon-Oke, Olatunji Odeyemi, Mobolanle Oniya

Abstract:

Urinary tract infection has become the most common bacterial infections in humans, both at the community and hospital settings; it has been reported in all age groups and in both sexes. This study was carried out in order to determine and evaluate the prevalence, current drug susceptibility pattern of the isolated organisms and identify the associated risk factors of UTIs among the pregnant women in Akure, Ondo State, Nigeria. A cross-sectional study was conducted on the urine of pregnant women, and socio-demographic information of the women was collected. A total of 300 clean midstream urine samples were collected, and a general urine microscopic examination and culture were carried out, the Microbact identification system was used to identify gram-negative bacteria. Out of the 300 urine samples cultured, 183(61.0%) yielded significant growth of urinary pathogens while 117(39.0%) yielded either insignificant growth or no growth of any urinary pathogen. Prevalence of UTI was significantly associated with the type of toilet used, symptoms of UTI, and previous history of urinary tract infection (p<0.05). Escherichia coli 58(31.7%) was the dominant pathogen isolated, and the least isolated uropathogens were Citrobacter freudii and Providencia retgerri 2(1.1%) respectively. Gram-negative bacteria showed 77.6%, 67.9%, and 61.2% susceptibility to ciprofloxacin, augmentin, and chloramphenicol, respectively. Resistance against septrin, chloramphenicol, sparfloxacin, amoxicillin, augmentin, gentamycin, pefloxacin, trivid, and streptomycin was observed in the range of 23.1 to 70.1%. Gram-positive uropathogens isolated showed high resistance to amoxicillin (68.4%) and high susceptibility to the remaining nine antibiotics in the range 65.8% to 89.5%. This study justifies that pregnant women are at high risk of UTI. Therefore screening of pregnant women during antenatal clinics should be considered very important to avoid complications. Health education with regular antenatal and personal hygiene is recommended as precautionary measures to UTI.

Keywords: pregnant women, prevalence, risk factor, UTIs

Procedia PDF Downloads 125
6740 Impact of Pharmacist-Led Care on Glycaemic Control in Patients with Type 2 Diabetes: A Randomised-Controlled Trial

Authors: Emmanuel A. David, Rebecca O. Soremekun, Roseline I. Aderemi-Williams

Abstract:

Background: The complexities involved in the management of diabetes mellitus require a multi-dimensional, multi-professional collaborative and continuous care by health care providers and a substantial self-care by the patients in order to achieve desired treatment outcomes. The effect of pharmacists’ care in the management of diabetes in resource-endowed nations is well documented in literature, but randomised-controlled assessment of the impact of pharmacist-led care among patients with diabetes in resource-limited settings like Nigeria and sub-Saharan Africa countries is scarce. Objective: To evaluate the impact of Pharmacist-led care on glycaemic control in patients with uncontrolled type 2 diabetes, using a randomised-controlled study design Methods: This study employed a prospective randomised controlled design, to assess the impact of pharmacist-led care on glycaemic control of 108 poorly controlled type 2 diabetic patients. A total of 200 clinically diagnosed type 2 diabetes patients were purposively selected using fasting blood glucose ≥ 7mmol/L and tested for long term glucose control using Glycated haemoglobin measure. One hundred and eight (108) patients with ≥ 7% Glycated haemoglobin were recruited for the study and assigned unique identification numbers. They were further randomly allocated to intervention and usual care groups using computer generated random numbers, with each group containing 54 subjects. Patients in the intervention group received pharmacist-structured intervention, including education, periodic phone calls, adherence counselling, referral and 6 months follow-up, while patients in usual care group only kept clinic appointments with their physicians. Data collected at baseline and six months included socio-demographic characteristics, fasting blood glucose, Glycated haemoglobin, blood pressure, lipid profile. With an intention to treat analysis, Mann-Whitney U test was used to compared median change from baseline in the primary outcome (Glycated haemoglobin) and secondary outcomes measure, effect size was computed and proportion of patients that reached target laboratory parameter were compared in both arms. Results: All enrolled participants (108) completed the study, 54 in each study. Mean age was 51±11.75 and majority were female (68.5%). Intervention patients had significant reduction in Glycated haemoglobin (-0.75%; P<0.001; η2 = 0.144), with greater proportion attaining target laboratory parameter after 6 months of care compared to usual care group (Glycated haemoglobin: 42.6% vs 20.8%; P=0.02). Furthermore, patients who received pharmacist-led care were about 3 times more likely to have better glucose control (AOR 2.718, 95%CI: 1.143-6.461) compared to usual care group. Conclusion: Pharmacist-led care significantly improved glucose control in patients with uncontrolled type 2 diabetes mellitus and should be integrated in the routine management of diabetes patients, especially in resource-limited settings.

Keywords: glycaemic control , pharmacist-led care, randomised-controlled trial , type 2 diabetes mellitus

Procedia PDF Downloads 109
6739 Optimization of Three Phase Squirrel Cage Induction Motor

Authors: Tunahan Sapmaz, Harun Etçi, İbrahim Şenol, Yasemin Öner

Abstract:

Rotor bar dimensions have a great influence on the air-gap magnetic flux density. Therefore, poor selection of this parameter during the machine design phase causes the air-gap magnetic flux density to be distorted. Thus, it causes noise, torque fluctuation, and losses in the induction motor. On the other hand, the change in rotor bar dimensions will change the resistance of the conductor, so the current will be affected. Therefore, the increase and decrease of rotor bar current affect operation, starting torque, and efficiency. The aim of this study is to examine the effect of rotor bar dimensions on the electromagnetic performance criteria of the induction motor. Modeling of the induction motor is done by the finite element method (FEM), which is a very powerful tool. In FEM, the results generally focus on performance criteria such as torque, torque fluctuation, efficiency, and current.

Keywords: induction motor, finite element method, optimization, rotor bar

Procedia PDF Downloads 112
6738 A Social Decision Support Mechanism for Group Purchasing

Authors: Lien-Fa Lin, Yung-Ming Li, Fu-Shun Hsieh

Abstract:

With the advancement of information technology and development of group commerce, people have obviously changed in their lifestyle. However, group commerce faces some challenging problems. The products or services provided by vendors do not satisfactorily reflect customers’ opinions, so that the sale and revenue of group commerce gradually become lower. On the other hand, the process for a formed customer group to reach group-purchasing consensus is time-consuming and the final decision is not the best choice for each group members. In this paper, we design a social decision support mechanism, by using group discussion message to recommend suitable options for group members and we consider social influence and personal preference to generate option ranking list. The proposed mechanism can enhance the group purchasing decision making efficiently and effectively and venders can provide group products or services according to the group option ranking list.

Keywords: social network, group decision, text mining, group commerce

Procedia PDF Downloads 477
6737 The Influence of Microsilica on the Cluster Cracks' Geometry of Cement Paste

Authors: Maciej Szeląg

Abstract:

The changing nature of environmental impacts, in which cement composites are operating, are causing in the structure of the material a number of phenomena, which result in volume deformation of the composite. These strains can cause composite cracking. Cracks are merging by propagation or intersect to form a characteristic structure of cracks known as the cluster cracks. This characteristic mesh of cracks is crucial to almost all building materials, which are working in service loads conditions. Particularly dangerous for a cement matrix is a sudden load of elevated temperature – the thermal shock. Resulting in a relatively short period of time a large value of a temperature gradient between the outer surface and the material’s interior can result in cracks formation on the surface and in the volume of the material. In the paper, in order to analyze the geometry of the cluster cracks of the cement pastes, the image analysis tools were used. Tested were 4 series of specimens made of two different Portland cement. In addition, two series include microsilica as a substitute for the 10% of the cement. Within each series, specimens were performed in three w/b indicators (water/binder): 0.4; 0.5; 0.6. The cluster cracks were created by sudden loading the samples by elevated temperature of 250°C. Images of the cracked surfaces were obtained via scanning at 2400 DPI. Digital processing and measurements were performed using ImageJ v. 1.46r software. To describe the structure of the cluster cracks three stereological parameters were proposed: the average cluster area - A ̅, the average length of cluster perimeter - L ̅, and the average opening width of a crack between clusters - I ̅. The aim of the study was to identify and evaluate the relationships between measured stereological parameters, and the compressive strength and the bulk density of the modified cement pastes. The tests of the mechanical and physical feature have been carried out in accordance with EN standards. The curves describing the relationships have been developed using the least squares method, and the quality of the curve fitting to the empirical data was evaluated using three diagnostic statistics: the coefficient of determination – R2, the standard error of estimation - Se, and the coefficient of random variation – W. The use of image analysis allowed for a quantitative description of the cluster cracks’ geometry. Based on the obtained results, it was found a strong correlation between the A ̅ and L ̅ – reflecting the fractal nature of the cluster cracks formation process. It was noted that the compressive strength and the bulk density of cement pastes decrease with an increase in the values of the stereological parameters. It was also found that the main factors, which impact on the cluster cracks’ geometry are the cement particles’ size and the general content of the binder in a volume of the material. The microsilica caused the reduction in the A ̅, L ̅ and I ̅ values compared to the values obtained by the classical cement paste’s samples, which is caused by the pozzolanic properties of the microsilica.

Keywords: cement paste, cluster cracks, elevated temperature, image analysis, microsilica, stereological parameters

Procedia PDF Downloads 237
6736 Effectiveness of Earthing System in Vertical Configurations

Authors: S. Yunus, A. Suratman, N. Mohamad Nor, M. Othman

Abstract:

This paper presents the measurement and simulation results by Finite Element Method (FEM) for earth resistance (RDC) for interconnected vertical ground rod configurations. The soil resistivity was measured using the Wenner four-pin Method, and RDC was measured using the Fall of Potential (FOP) method, as outlined in the standard. Genetic Algorithm (GA) is employed to interpret the soil resistivity to that of a 2-layer soil model. The same soil resistivity data that were obtained by Wenner four-pin method were used in FEM for simulation. This paper compares the results of RDC obtained by FEM simulation with the real measurement at field site. A good agreement was seen for RDC obtained by measurements and FEM. This shows that FEM is a reliable software to be used for design of earthing systems. It is also found that the parallel rod system has a better performance compared to a similar setup using a grid layout.

Keywords: earthing system, earth electrodes, finite element method, genetic algorithm, earth resistances

Procedia PDF Downloads 97
6735 Anti-Hypertensive Effect of Proteolysate Generated from Actinopyga lecanora in Rats

Authors: Mahdokht Sadeghvishkaei, Azizah Abdul-Hamid, Amin Ismail, Nazamid Saari

Abstract:

Hypertension is a common and serious chronic health problem and known as the most important risk factor for development of many diseases such as stroke. Since angiotensin I-converting enzyme (ACE) is the key enzyme involved in blood pressure, one of the well accepted mechanisms to control hypertension is through ACE inhibition. The ACE inhibitory effect of Actinopyga lecanora (stone fish) proteolysate in vitro had been reported. Hence, this study aimed to evaluate the ACE inhibitory potential of Actinopyga lecanora proteolysate in vivo in normotensive rats. Therefore the ACE inhibitory capability of the proteolysate to prevent increasing systolic blood pressure, after inducing hypertension by angiotensin I was examined. The pre-fed rats with the proteolysates at various doses (200, 400, 800 mg/kg body weight) revealed the significant (p ≤ 0.05) suppression effect compared with control groups. Furthermore, different doses of the proteolysate (200, 400, 800 mg/kg body weight) were examined to find its optimum effective dose. Results depicted that 800 mg proteolysate/kg body weight significantly reduced systolic blood pressure without negative effect on normal blood pressure (p ≤ 0.05). Furthermore, Sub-acute toxicity study based on OECD guideline demonstrated the safety of the proteolysate in vivo. The present study indicated that the proteolysate at a dose of 1000 mg/kg daily for 14 days did not cause toxicity signs such as death, changes in activity, or piloerection. Since there are no significant differences between treated groups and control groups, hematological and biochemical analysis confirmed safety of the proteolysate (p > 0.05). In addition, there were no significant differences between organs weights of the treated groups and the control groups. Morphologically, neither histopathological changes, nor gross abnormalities were observed. However, the proteolysate caused significant decrease in body weight in relation to the control groups (p ≤ 0.05) probably due to appetite stimulation by the proteolysate, leading to decreased food consumption in sub-acute group. It is concluded that the proteolysate generated from Actinopyga lecanora possess a significant anti-hypertensive effect and would be potentially used as natural alternative of ACE inhibitors.

Keywords: ACE inhibition, Actinopyga lecanora, anti-hypertensive activity, bioactive peptides, normotensive rats

Procedia PDF Downloads 420
6734 Analysis of Universal Mobile Telecommunications Service (UMTS) Planning Using High Altitude Platform Station (HAPS)

Authors: Yosika Dian Komala, Uke Kurniawan Usman, Yuyun Siti Rohmah

Abstract:

The enable technology fills up needs of high-speed data service is Universal Mobile Telecommunications Service (UMTS). UMTS has a data rate up to 2Mbps.UMTS terrestrial system has a coverage area about 1-2km. High Altitude Platform Station (HAPS) can be built by a macro cell that is able to serve the wider area. Design method of UMTS using HAPS is planning base on coverage and capacity. The planning method is simulated with 2.8.1 Atoll’s software. Determination of radius of the cell based on the coverage uses free space loss propagation model. While the capacity planning to determine the average cell through put is available with the Offered Bit Quantity (OBQ).

Keywords: UMTS, HAPS, coverage planning, capacity planning, signal level, Ec/Io, overlapping zone, throughput

Procedia PDF Downloads 620
6733 Relationship Between Insulin Resistance and Some Coagulation and Fibrinolytic Parameters in Subjects With Metabolic Syndrome

Authors: Amany Ragab, Nashwa Khairat Abousamra, Omayma Saleh, Asmaa Higazy

Abstract:

Insulin resistance syndrome has been shown to be associated with many coagulation and fibrinolytic proteins and these associations suggest that some coagulation and fibrinolytic proteins have a role in atherothrombotic disorders. This study was conducted to determine the levels of some of the haemostatic parameters in subjects having metabolic syndrome and to correlate these values with the anthropometric and metabolic variables associated with this syndrome. The study included 46 obese non diabetic subjects of whom 28 subjects(group1) fulfilled the ATP III criteria of the metabolic syndrome and 18 subjects (group2) did not have metabolic syndrome as well as 14 lean subjects (group 3) of matched age and sex as a control group. Clinical and laboratory evaluation of the study groups stressed on anthropometric measurements (weight, height, body mass index, waist circumference, and sagittal abdominal diameter), blood pressure, and laboratory measurements of fasting plasma glucose, fasting insulin, serum lipids, tissue plasminogen activator (t-PA), antithrombin III activity (ATIII), protein C and von Willebrand factor (vWf) antigen. There was significant increase in the concentrations of t-PA and vWf antigens in subjects having metabolic syndrome (group 1) in comparison to the other groups while there were non-significant changes in the levels of protein C antigen and AT III activity. Both t-PA and vWf showed significant correlation with HOMA-IR as a measure of insulin sensitivity. The t-PA showed also significant correlation with most of the variables of metabolic syndrome including waist circumference, BMI, systolic blood pressure, fasting plasma glucose, fasting insulin, and HDL cholesterol. On the other hand, vWf showed significant correlations with fasting plasma glucose, fasting insulin and sagital abdominal diameter, with non-significant correlations with the other variables. Haemostatic and fibrinolytic parameters should be included in the features and characterization of the insulin resistance syndrome. t-PA and vWf antigens concentrations were increased in subjects with metabolic syndrome and correlated with the HOMA-IR measure of insulin sensitivity. Taking into consideration that both t-PA and vWf are mainly released from vascular endothelium, these findings could be an indicator of endothelial dysfunction in that group of subjects.

Keywords: insulin resistance, obesity, metabolic syndrome, coagulation

Procedia PDF Downloads 125
6732 Soil/Phytofisionomy Relationship in Southeast of Chapada Diamantina, Bahia, Brazil

Authors: Marcelo Araujo da Nóbrega, Ariel Moura Vilas Boas

Abstract:

This study aims to characterize the physicochemical aspects of the soils of southeastern Chapada Diamantina - Bahia related to the phytophysiognomies of this area, rupestrian field, small savanna (savanna fields), small dense savanna (savanna fields), savanna (Cerrado), dry thorny forest (Caatinga), dry thorny forest/savanna, scrub (Carrasco - ecotone), forest island (seasonal semi-deciduous forest - Capão) and seasonal semi-deciduous forest. To achieve the research objective, soil samples were collected in each plant formation and analyzed in the soil laboratory of ESALQ - USP in order to identify soil fertility through the determination of pH, organic matter, phosphorus, potassium, calcium, magnesium, potential acidity, sum of bases, cation exchange capacity and base saturation. The composition of soil particles was also checked; that is, the texture, step made in the terrestrial ecosystems laboratory of the Department of Ecology of USP and in the soil laboratory of ESALQ. Another important factor also studied was to show the variations in the vegetation cover in the region as a function of soil moisture in the different existing physiographic environments. Another study carried out was a comparison between the average soil moisture data with precipitation data from three locations with very different phytophysiognomies. The soils found in this part of Bahia can be classified into 5 classes, with a predominance of oxisols. All of these classes have a great diversity of physical and chemical properties, as can be seen in photographs and in particle size and fertility analyzes. The deepest soils are located in the Central Pediplano of Chapada Diamantina where the dirty field, the clean field, the executioner and the semideciduous seasonal forest (Capão) are located, and the shallower soils were found in the rupestrian field, dry thorny forest, and savanna fields, the latter located on a hillside. As for the variations in water in the region's soil, the data indicate that there were large spatial variations in humidity in both the rainy and dry periods.

Keywords: Bahia, Brazil, chapada diamantina, phytophysiognomies, soils

Procedia PDF Downloads 127
6731 Analysis Rotor Bearing System Dynamic Interaction with Bearing Supports

Authors: V. T. Ngo, D. M. Xie

Abstract:

Frequently, in the design of machines, some of parameters that directly affect the rotor dynamics of the machines are not accurately known. In particular, bearing stiffness support is one such parameter. One of the most basic principles to grasp in rotor dynamics is the influence of the bearing stiffness on the critical speeds and mode shapes associated with a rotor-bearing system. Taking a rig shafting as an example, this paper studies the lateral vibration of the rotor with multi-degree-of-freedom by using Finite Element Method (FEM). The FEM model is created and the eigenvalues and eigenvectors are calculated and analyzed to find natural frequencies, critical speeds, mode shapes. Then critical speeds and mode shapes are analyzed by set bearing stiffness changes. The model permitted to identify the critical speeds and bearings that have an important influence on the vibration behavior.

Keywords: lateral vibration, finite element method, rig shafting, critical speed

Procedia PDF Downloads 324
6730 Adolescent-Parent Relationship as the Most Important Factor in Preventing Mood Disorders in Adolescents: An Application of Artificial Intelligence to Social Studies

Authors: Elżbieta Turska

Abstract:

Introduction: One of the most difficult times in a person’s life is adolescence. The experiences in this period may shape the future life of this person to a large extent. This is the reason why many young people experience sadness, dejection, hopelessness, sense of worthlessness, as well as losing interest in various activities and social relationships, all of which are often classified as mood disorders. As many as 15-40% adolescents experience depressed moods and for most of them they resolve and are not carried into adulthood. However, (5-6%) of those affected by mood disorders develop the depressive syndrome and as many as (1-3%) develop full-blown clinical depression. Materials: A large questionnaire was given to 2508 students, aged 13–16 years old, and one of its parts was the Burns checklist, i.e. the standard test for identifying depressed mood. The questionnaire asked about many aspects of the student’s life, it included a total of 53 questions, most of which had subquestions. It is important to note that the data suffered from many problems, the most important of which were missing data and collinearity. Aim: In order to identify the correlates of mood disorders we built predictive models which were then trained and validated. Our aim was not to be able to predict which students suffer from mood disorders but rather to explore the factors influencing mood disorders. Methods: The problems with data described above practically excluded using all classical statistical methods. For this reason, we attempted to use the following Artificial Intelligence (AI) methods: classification trees with surrogate variables, random forests and xgboost. All analyses were carried out with the use of the mlr package for the R programming language. Resuts: The predictive model built by classification trees algorithm outperformed the other algorithms by a large margin. As a result, we were able to rank the variables (questions and subquestions from the questionnaire) from the most to least influential as far as protection against mood disorder is concerned. Thirteen out of twenty most important variables reflect the relationships with parents. This seems to be a really significant result both from the cognitive point of view and also from the practical point of view, i.e. as far as interventions to correct mood disorders are concerned.

Keywords: mood disorders, adolescents, family, artificial intelligence

Procedia PDF Downloads 88
6729 A Hybrid Distributed Algorithm for Solving Job Shop Scheduling Problem

Authors: Aydin Teymourifar, Gurkan Ozturk

Abstract:

In this paper, a distributed hybrid algorithm is proposed for solving the job shop scheduling problem. The suggested method executes different artificial neural networks, heuristics and meta-heuristics simultaneously on more than one machine. The neural networks are used to control the constraints of the problem while the meta-heuristics search the global space and the heuristics are used to prevent the premature convergence. To attain an efficient distributed intelligent method for solving big and distributed job shop scheduling problems, Apache Spark and Hadoop frameworks are used. In the algorithm implementation and design steps, new approaches are applied. Comparison between the proposed algorithm and other efficient algorithms from the literature shows its efficiency, which is able to solve large size problems in short time.

Keywords: distributed algorithms, Apache Spark, Hadoop, job shop scheduling, neural network

Procedia PDF Downloads 373
6728 Earthquake Risk Assessment Using Out-of-Sequence Thrust Movement

Authors: Rajkumar Ghosh

Abstract:

Earthquakes are natural disasters that pose a significant risk to human life and infrastructure. Effective earthquake mitigation measures require a thorough understanding of the dynamics of seismic occurrences, including thrust movement. Traditionally, estimating thrust movement has relied on typical techniques that may not capture the full complexity of these events. Therefore, investigating alternative approaches, such as incorporating out-of-sequence thrust movement data, could enhance earthquake mitigation strategies. This review aims to provide an overview of the applications of out-of-sequence thrust movement in earthquake mitigation. By examining existing research and studies, the objective is to understand how precise estimation of thrust movement can contribute to improving structural design, analyzing infrastructure risk, and developing early warning systems. The study demonstrates how to estimate out-of-sequence thrust movement using multiple data sources, including GPS measurements, satellite imagery, and seismic recordings. By analyzing and synthesizing these diverse datasets, researchers can gain a more comprehensive understanding of thrust movement dynamics during seismic occurrences. The review identifies potential advantages of incorporating out-of-sequence data in earthquake mitigation techniques. These include improving the efficiency of structural design, enhancing infrastructure risk analysis, and developing more accurate early warning systems. By considering out-of-sequence thrust movement estimates, researchers and policymakers can make informed decisions to mitigate the impact of earthquakes. This study contributes to the field of seismic monitoring and earthquake risk assessment by highlighting the benefits of incorporating out-of-sequence thrust movement data. By broadening the scope of analysis beyond traditional techniques, researchers can enhance their knowledge of earthquake dynamics and improve the effectiveness of mitigation measures. The study collects data from various sources, including GPS measurements, satellite imagery, and seismic recordings. These datasets are then analyzed using appropriate statistical and computational techniques to estimate out-of-sequence thrust movement. The review integrates findings from multiple studies to provide a comprehensive assessment of the topic. The study concludes that incorporating out-of-sequence thrust movement data can significantly enhance earthquake mitigation measures. By utilizing diverse data sources, researchers and policymakers can gain a more comprehensive understanding of seismic dynamics and make informed decisions. However, challenges exist, such as data quality difficulties, modelling uncertainties, and computational complications. To address these obstacles and improve the accuracy of estimates, further research and advancements in methodology are recommended. Overall, this review serves as a valuable resource for researchers, engineers, and policymakers involved in earthquake mitigation, as it encourages the development of innovative strategies based on a better understanding of thrust movement dynamics.

Keywords: earthquake, out-of-sequence thrust, disaster, human life

Procedia PDF Downloads 62
6727 Investigation of Cascade Loop Heat Pipes

Authors: Nandy Putra, Atrialdipa Duanovsah, Kristofer Haliansyah

Abstract:

The aim of this research is to design a LHP with low thermal resistance and low condenser temperature. A Self-designed cascade LHP was tested by using biomaterial, sintered copper powder, and aluminum screen mesh as the wick. Using pure water as the working fluid for the first level of the LHP and 96% alcohol as the working fluid for the second level of LHP, the experiments were run with 10W, 20W, and 30W heat input. Experimental result shows that the usage of biomaterial as wick could reduce more temperature at evaporator than by using sintered copper powder and screen mesh up to 22.63% and 37.41% respectively. The lowest thermal resistance occurred during the usage of biomaterial as wick of heat pipe, which is 2.06 oC/W. The usage of cascade system could be applied to LHP to reduce the temperature at condenser and reduced thermal resistance up to 17.6%.

Keywords: biomaterial, cascade loop heat pipe, screen mesh, sintered Cu

Procedia PDF Downloads 246
6726 Fuzzy Logic Control for Flexible Joint Manipulator: An Experimental Implementation

Authors: Sophia Fry, Mahir Irtiza, Alexa Hoffman, Yousef Sardahi

Abstract:

This study presents an intelligent control algorithm for a flexible robotic arm. Fuzzy control is used to control the motion of the arm to maintain the arm tip at the desired position while reducing vibration and increasing the system speed of response. The Fuzzy controller (FC) is based on adding the tip angular position to the arm deflection angle and using their sum as a feedback signal to the control algorithm. This reduces the complexity of the FC in terms of the input variables, number of membership functions, fuzzy rules, and control structure. Also, the design of the fuzzy controller is model-free and uses only our knowledge about the system. To show the efficacy of the FC, the control algorithm is implemented on the flexible joint manipulator (FJM) developed by Quanser. The results show that the proposed control method is effective in terms of response time, overshoot, and vibration amplitude.

Keywords: fuzzy logic control, model-free control, flexible joint manipulators, nonlinear control

Procedia PDF Downloads 82
6725 Mathematical Modeling of Skin Condensers for Domestic Refrigerator

Authors: Nitin Ghule, S. G. Taji

Abstract:

A mathematical model of hot-wall condensers used in refrigerators is presented. The model predicts the heat transfer characteristics of condenser and the effects of various design and operating parameters on condenser tube length and capacity. A finite element approach was used to model the condenser. The condenser tube is divided into elemental units, with each element consisting of adhesive tape, refrigerant tube and outer metal sheet. The heat transfer characteristics of each section are then analyzed by considering the heat transfer through the tube wall, tape and the outer sheet. Variations in inner heat transfer coefficient and pressure drop are considered depending on temperature, fluid phase, type of flow and orientation of tube. Variation in outer heat transfer coefficient is also taken into account. Various materials were analysed for the tube, tape and outer sheet.

Keywords: condenser, domestic refrigerator, heat transfer, mathematical model

Procedia PDF Downloads 441
6724 Closed-Form Sharma-Mittal Entropy Rate for Gaussian Processes

Authors: Septimia Sarbu

Abstract:

The entropy rate of a stochastic process is a fundamental concept in information theory. It provides a limit to the amount of information that can be transmitted reliably over a communication channel, as stated by Shannon's coding theorems. Recently, researchers have focused on developing new measures of information that generalize Shannon's classical theory. The aim is to design more efficient information encoding and transmission schemes. This paper continues the study of generalized entropy rates, by deriving a closed-form solution to the Sharma-Mittal entropy rate for Gaussian processes. Using the squeeze theorem, we solve the limit in the definition of the entropy rate, for different values of alpha and beta, which are the parameters of the Sharma-Mittal entropy. In the end, we compare it with Shannon and Rényi's entropy rates for Gaussian processes.

Keywords: generalized entropies, Sharma-Mittal entropy rate, Gaussian processes, eigenvalues of the covariance matrix, squeeze theorem

Procedia PDF Downloads 499
6723 Using a Design Structure Method to Support Technology Roadmapping for Product-Service Integrated Systems

Authors: Heungwook Son, Sungjoo Lee

Abstract:

Recently, due to intensifying competition in several industries, the importance of meeting customer requirements has increased. The role that service plays in satisfying customer‘s requirements is key area of focus. Thus, the concept of using product development-research in the service system has been actively practiced. As strategic decision making tool, various types of the technology roadmap were suggested in the product-service system (PSS). However, the technology roadmap was configured a top-down form around the technologies of the elements. The limitation is that it hard for it to indicate a variety of interrelations. In response, this paper suggests using the planning support tool of PSS for a DSM for the technology roadmap; it consists of the relationship of product-service-technology as a bottom-up form. Therefore, nine types of the technology roadmap of PSS exist. The first defines the relationship of product-service-technology. The second phase identifies output when of the technology roadmaps are adapted to the DSM process. Finally, the DSM-based forms of each type of technology roadmap are presented through case studies.

Keywords: DSM, technology roadmap, PSS, product-service system, bottom-up

Procedia PDF Downloads 362