Search results for: functional core
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4768

Search results for: functional core

4768 Competencies and Training Needs for School Sport Managers in the North West Province, South Africa

Authors: Elriena Eksteen, Yolandi Willemse, Dawie D. J. Malan, Suria Ellis

Abstract:

It is important to understand which competencies are needed for managerial and administrative effectiveness of school sport managers with regard to the design, delivery and direction of school sport programmes. The purpose of this study was to determine the competencies and training needs for secondary school sport managers in the North West Province. Data were gathered from 79 school sport managers in the North West Province by means of a validated self-compiled questionnaire. Descriptive statistics, factor analysis and a dependent t-test were used to compare which competencies school sport managers perceive as important in their work with the competencies they actually perform. Functional competencies and core competencies were both found to be important for managing school sport effectively. There were statistically significant differences between the perceived importance of competencies and the frequency with which competencies were actually performed. Respondents attached greater importance to functional and core competencies than the proportion of time spent actually performing them. Furthermore, results indicated the need to train teachers in managing sport finance, sport facilities and human resources, as well as presenting workshops in public relations, sport marketing and sport organisation.

Keywords: competencies, functional competencies, core competencies, school sport manager, training needs

Procedia PDF Downloads 427
4767 Seismic Behavior of Short Core Buckling Restrained Braces

Authors: Nader Hoveidae

Abstract:

This paper investigates the seismic behavior of a new type of buckling restrained braces (BRBs) called "Short Core BRBs" in which a shorter core segment is used as an energy dissipating part and an elastic part is serially connected to the core. It seems that a short core BRB is easy to be fabricated, inspected and replaced after a severe earthquake. In addition, the energy dissipating capacity in a short core BRB is higher because of larger core strains. However, higher core strain demands result in high potential of low-cycle fatigue fracture. In this paper, a strategy is proposed to estimate the minimum core length in a short core BRBs. The seismic behavior of short core buckling restrained brace is experimentally examined. The results revealed that the short core buckling restrained brace is able to sustain large inelastic strains without any significant instability or strength degradation.

Keywords: short core, Buckling Restrained Brace, finite element analysis, cyclic test

Procedia PDF Downloads 360
4766 Estimation of Functional Response Model by Supervised Functional Principal Component Analysis

Authors: Hyon I. Paek, Sang Rim Kim, Hyon A. Ryu

Abstract:

In functional linear regression, one typical problem is to reduce dimension. Compared with multivariate linear regression, functional linear regression is regarded as an infinite-dimensional case, and the main task is to reduce dimensions of functional response and functional predictors. One common approach is to adapt functional principal component analysis (FPCA) on functional predictors and then use a few leading functional principal components (FPC) to predict the functional model. The leading FPCs estimated by the typical FPCA explain a major variation of the functional predictor, but these leading FPCs may not be mostly correlated with the functional response, so they may not be significant in the prediction for response. In this paper, we propose a supervised functional principal component analysis method for a functional response model with FPCs obtained by considering the correlation of the functional response. Our method would have a better prediction accuracy than the typical FPCA method.

Keywords: supervised, functional principal component analysis, functional response, functional linear regression

Procedia PDF Downloads 75
4765 NFC Kenaf Core Graphene Paper: In-situ Method Application

Authors: M. A. Izzati, R. Rosazley, A. W. Fareezal, M. Z. Shazana, I. Rushdan, M. Jani

Abstract:

Ultrasonic probe were using to produce nanofibrillated cellulose (NFC) kenaf core. NFC kenaf core and graphene was mixed using in-situ method with the 5V voltage for 24 hours. The resulting NFC graphene paper was characterized by field emission scanning electron microscopy (FESEM), fourier transformed infrared (FTIR) spectra and thermogavimetric analysis (TGA). The properties of NFC kenaf core graphene paper are compared with properties of pure NFC kenaf core paper.

Keywords: NFC, kenaf core, graphene, in-situ method

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4764 Classifying the Role of Technology in Technology Development

Authors: Hyun Joung No, Chul Lee

Abstract:

Even though technology evolves and develops through interaction with each other, not all technologies contribute to the development of technology equally. While some technologies play a central role in developing technology, others play a secondary role. The role of the technological components can be classified as core or non-core (peripheral) technology. The core technologies have a considerable knowledge interaction with other technological components while the non-core technologies barely interact with others within the system. This study introduces the concept that classifies the technological components into core or peripheral technology according to their role and importance in the technology field. The study adapted the social network analysis to examine the relationship between technological components. Using a continuous core-periphery analysis, it identifies the technological network structure and classifies the core and peripheral nodes. Based on their knowledge inflow/outflow direction and their dependence/influence on core technologies, the technological clusters are classified into four categories: (1) high dependence and high influence on core technology, (2) high dependence and low influence on core technology, (3) low dependence and high influence on core technology, and (4) low dependence and low influence on core technology.

Keywords: core technology, periphery technology, technological components, technological role

Procedia PDF Downloads 538
4763 Testifying in Court as a Victim of Crime for Persons with Little or No Functional Speech: Vocabulary Implications

Authors: Robyn White, Juan Bornman, Ensa Johnson

Abstract:

People with disabilities are at a high risk of becoming victims of crime. Individuals with little or no functional speech (LNFS) face an even higher risk. One way of reducing the risk of remaining a victim of crime is to face the alleged perpetrator in court as a witness – therefore it is important for a person with LNFS who has been a victim of crime to have the required vocabulary to testify in court. The aim of this study was to identify and describe the core and fringe legal vocabulary required by illiterate victims of crime, who have little or no functional speech, to testify in court as witnesses. A mixed-method, the exploratory sequential design consisting of two distinct phases was used to address the aim of the research. The first phase was of a qualitative nature and included two different data sources, namely in-depth semi-structured interviews and focus group discussions. The overall aim of this phase was to identify and describe core and fringe legal vocabulary and to develop a measurement instrument based on these results. Results from Phase 1 were used in Phase 2, the quantitative phase, during which the measurement instrument (a custom-designed questionnaire) was socially validated. The results produced six distinct vocabulary categories that represent the legal core vocabulary and 99 words that represent the legal fringe vocabulary. The findings suggested that communication boards should be individualised to the individual and the specific crime. It is believed that the vocabulary lists developed in this study act as a valid and reliable springboard from which communication boards can be developed. Recommendations were therefore made to develop an Alternative and Augmentative Communication Resource Tool Kit to assist the legal justice system.

Keywords: augmentative and alternative communication, person with little or no functional speech, sexual crimes, testifying in court, victim of crime, witness competency

Procedia PDF Downloads 480
4762 Flexural Test of Diversing Foam Core Sandwich Composites

Authors: Santhana Krishnan R, Preetha C

Abstract:

Sandwich construction with strong and stiffness facing and light weight cores is increasingly cores being used in structures where the predominant loads are flexural. The objective of this study is to improve the flexural performances of foam core sandwich composite via structural core modifications considering the ease of application. The performances of single core perforated and divided core perforated sandwich composites are compared with each other. The future demands of sandwich composites in recent years on aeronautics and marine industries are being increasing in their research needs and these materials has their superior properties for upgrading engineering products.

Keywords: sandwich composites, perforated cores, flexural test, single and divided core perforated

Procedia PDF Downloads 160
4761 Biocompatibility and Sensing Ability of Highly Luminescent Synthesized Core-Shell Quantum Dots

Authors: Mohan Singh Mehata, R. K. Ratnesh

Abstract:

CdSe, CdSe/ZnS, and CdSe/CdS core-shell quantum dots (QDs) of 3-4 nm were developed by using chemical route and following successive ion layer adsorption and reaction (SILAR) methods. The prepared QDs have been examined by using X-ray diffraction, high-resolution electron microscopy and optical spectroscopy. The photoluminescence (PL) quantum yield (QY) of core-shell QDs increases with respect to the core, indicating that the radiative rate increases by the formation of shell around core, as evident by the measurement of PL lifetime. Further, the PL of bovine serum albumin is quenched strongly by the presence of core-shall QDs and follow the Stern-Volmer (S-V) relation, whereas the lifetime does not follow the S-V relation, demonstrating that the observed quenching is predominantly static in nature. Among all the QDs, the CdSe/ZnS QDs shows the least cytotoxicity hence most biocompatibility.

Keywords: biocompatibility, core-shell quantum dots, photoluminescence and lifetime, sensing ability

Procedia PDF Downloads 236
4760 Local Buckling of Web-Core and Foam-Core Sandwich Panels

Authors: Ali N. Suri, Ahmad A. Al-Makhlufi

Abstract:

Sandwich construction is widely accepted as a method of construction especially in the aircraft industry. It is a type of stressed skin construction formed by bonding two thin faces to a thick core, the faces resist all of the applied edge loads and provide all or nearly all of the required rigidities, the core spaces the faces to increase cross section moment of inertia about common neutral axis and transmit shear between them provides a perfect bond between core and faces is made. Material for face sheets can be of metal or reinforced plastics laminates, core material can be metallic cores of thin sheets forming corrugation or honeycomb, or non-metallic core of Balsa wood, plastic foams, or honeycomb made of reinforced plastics. For in plane axial loading web core and web-foam core Sandwich panels can fail by local buckling of plates forming the cross section with buckling wave length of the order of length of spacing between webs. In this study local buckling of web core and web-foam core Sandwich panels is carried out for given materials of facing and core, and given panel overall dimension for different combinations of cross section geometries. The Finite Strip Method is used for the analysis, and Fortran based computer program is developed and used.

Keywords: local buckling, finite strip, sandwich panels, web and foam core

Procedia PDF Downloads 351
4759 Identification of Transformer Core Vibrations and the Effect of Third Harmonic in the Electricity Grid

Authors: Setareh Gorji Ghalamestani, Lieven Vandevelde, Jan Melkebeek

Abstract:

In this work, an experimental technique is applied for the measurements of the vibrations and deformation of a test transformer core. Since the grid voltage contains some higher harmonics, in addition to a purely sinusoidal magnetisation of the core the presence of third harmonic is also studied. The vibrations of the transformer core for points as well as the surface scan of the leg show more deformation in the corners of the leg than the middle of the leg. The influence of the higher harmonic of the magnetisation on the core deformation is also more significant in the corners of the leg. The core deformation shape under a sinusoidal magnetisation with a higher harmonic is more wavy and fluctuating than that under a purely sinusoidal magnetisation.

Keywords: vibrations and noise, transformer, vibration measurements, laser vibrometer, higher harmonic

Procedia PDF Downloads 368
4758 Functional Neural Network for Decision Processing: A Racing Network of Programmable Neurons Where the Operating Model Is the Network Itself

Authors: Frederic Jumelle, Kelvin So, Didan Deng

Abstract:

In this paper, we are introducing a model of artificial general intelligence (AGI), the functional neural network (FNN), for modeling human decision-making processes. The FNN is composed of multiple artificial mirror neurons (AMN) racing in the network. Each AMN has a similar structure programmed independently by the users and composed of an intention wheel, a motor core, and a sensory core racing at a specific velocity. The mathematics of the node’s formulation and the racing mechanism of multiple nodes in the network will be discussed, and the group decision process with fuzzy logic and the transformation of these conceptual methods into practical methods of simulation and in operations will be developed. Eventually, we will describe some possible future research directions in the fields of finance, education, and medicine, including the opportunity to design an intelligent learning agent with application in AGI. We believe that FNN has a promising potential to transform the way we can compute decision-making and lead to a new generation of AI chips for seamless human-machine interactions (HMI).

Keywords: neural computing, human machine interation, artificial general intelligence, decision processing

Procedia PDF Downloads 125
4757 Study on Clarification of the Core Technology in a Monozukuri Company

Authors: Nishiyama Toshiaki, Tadayuki Kyountani, Nguyen Huu Phuc, Shigeyuki Haruyama, Oke Oktavianty

Abstract:

It is important to clarify the company’s core technology in product development process to strengthen their power in providing technology that meets the customer requirement. QFD method is adopted to clarify the core technology through identifying the high element technologies that are related to the voice of customer, and offer the most delightful features for customer. AHP is used to determine the importance of evaluating factors. A case study was conducted by using this approach in Japan’s Monozukuri Company (so called manufacturing company) to clarify their core technology based on customer requirements.

Keywords: core technology, QFD, voices of customer, analysis procedure

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4756 A Comprehensive Review of Yoga and Core Strength: Strengthening Core Muscles as Important Method for Injury Prevention (Lower Back Pain) and Performance Enhancement in Sports

Authors: Pintu Modak

Abstract:

The core strength is essential not only for athletes but also for everyone to perform everyday's household chores with ease and efficiency. Core strength means to strengthen the muscles deep within the abdomen which connect to the spine and pelvis which control the position and movement of the central portion of the body. Strengthening of core muscles is important for injury prevention (lower back pain) and performance enhancement in sports. The purpose of the study was to review the literature and findings on the effects of Yoga exercise as a part of sports training method and fitness programs. Fifteen papers were found to be relevant for this review. There are five simple yoga poses: Ardha Phalakasana (Low plank), Vasisthasana (side plank), Purvottanasana (inclined plane), Sarvangasana (shoulder stand), and Virabhadrasana (Warrior) are found to be very effective for strengthening core muscles. They are the most effective poses to build core strength and flexibility to the core muscles. The study suggests that sports and fitness trainers should include these yoga exercises in their programs to strengthen core muscles.

Keywords: core strength, yoga, injuries, lower back

Procedia PDF Downloads 276
4755 Effect of Core Puncture Diameter on Bio-Char Kiln Efficiency

Authors: W. Intagun, T. Khamdaeng, P. Prom-ngarm, N. Panyoyai

Abstract:

Biochar has been used as a soil amendment since it has high porous structure and has proper nutrients and chemical properties for plants. Product yields produced from biochar kiln are dependent on process parameters and kiln types used. The objective of this research is to investigate the effect of core puncture diameter on biochar kiln efficiency, i.e., yields of biochar and produced gas. Corncobs were used as raw material to produce biochar. Briquettes from agricultural wastes were used as fuel. Each treatment was performed by changing the core puncture diameter. From the experiment, it is revealed that the yield of biochar at the core puncture diameter of 3.18 mm, 4.76 mm, and 6.35 mm was 10.62 wt. %, 24.12 wt. %, and 12.24 wt. %, of total solid yields, respectively. The yield of produced gas increased with increasing the core puncture diameter. The maximum percentage by weight of the yield of produced gas was 81.53 wt. % which was found at the core puncture diameter of 6.35 mm. The core puncture diameter was furthermore found to affect the temperature distribution inside the kiln and its thermal efficiency. In conclusion, the high efficient biochar kiln can be designed and constructed by using the proper core puncture diameter.

Keywords: anila stove, bio-char, soil conditioning materials, temperature distribution

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4754 Chitosan-Whey Protein Isolate Core-Shell Nanoparticles as Delivery Systems

Authors: Zahra Yadollahi, Marjan Motiei, Natalia Kazantseva, Petr Saha

Abstract:

Chitosan (CS)-whey protein isolate (WPI) core-shell nanoparticles were synthesized through self-assembly of whey protein isolated polyanions and chitosan polycations in the presence of tripolyphosphate (TPP) as a crosslinker. The formation of this type of nanostructures with narrow particle size distribution is crucial for developing delivery systems since the functional characteristics highly depend on their sizes. To achieve this goal, the nanostructure was optimized by varying the concentrations of WPI, CS, and TPP in the reaction mixture. The chemical characteristics, surface morphology, and particle size of the nanoparticles were evaluated.

Keywords: whey protein isolated, chitosan, nanoparticles, delivery system

Procedia PDF Downloads 93
4753 A Fundamental Functional Equation for Lie Algebras

Authors: Ih-Ching Hsu

Abstract:

Inspired by the so called Jacobi Identity (x y) z + (y z) x + (z x) y = 0, the following class of functional equations EQ I: F [F (x, y), z] + F [F (y, z), x] + F [F (z, x), y] = 0 is proposed, researched and generalized. Research methodologies begin with classical methods for functional equations, then evolve into discovering of any implicit algebraic structures. One of this paper’s major findings is that EQ I, under two additional conditions F (x, x) = 0 and F (x, y) + F (y, x) = 0, proves to be a fundamental functional equation for Lie Algebras. Existence of non-trivial solutions for EQ I can be proven by defining F (p, q) = [p q] = pq –qp, where p and q are quaternions, and pq is the quaternion product of p and q. EQ I can be generalized to the following class of functional equations EQ II: F [G (x, y), z] + F [G (y, z), x] + F [G (z, x), y] = 0. Concluding Statement: With a major finding proven, and non-trivial solutions derived, this research paper illustrates and provides a new functional equation scheme for studies in two major areas: (1) What underlying algebraic structures can be defined and/or derived from EQ I or EQ II? (2) What conditions can be imposed so that conditional general solutions to EQ I and EQ II can be found, investigated and applied?

Keywords: fundamental functional equation, generalized functional equations, Lie algebras, quaternions

Procedia PDF Downloads 223
4752 Microstructural Investigations of Metal Oxides Encapsulated Thermochromic Materials

Authors: Yusuf Emirov, Abdullatif Hakami, Prasanta K Biswas, Elias K Stefanakos, Sesha S Srinivasan

Abstract:

This study is aimed to develop microencapsulated thermochromic materials and the analysis of core-shell formation using high resolution electron microscopy. The candidate metal oxides (e.g., titanium oxide and silicon oxide) used for the microencapsulation of thermochromic materials are based on the microemulsion route that involves the micelle formation using different surfactants. The effectiveness of the core-shell microstructure formationrevealed the influence of surfactants and the metal oxide precursor concentrations. Additionally, a detailed thermal and color chromic behavior of these core-shell microcapsules are evaluated with the pristine thermochromic dye particles.

Keywords: core-shell thermochromic materials, core-shell microstructure formation, thermal and color chromic behavior of core-shell microcapsules, development micro-capsulated thermochromic materials

Procedia PDF Downloads 158
4751 Consumer Choice Determinants in Context of Functional Food

Authors: E. Grochowska-Niedworok, K. Brukało, M. Kardas

Abstract:

The aim of this study was to analyze and evaluate the consumption of functional food by consumers by: age, sex, formal education level, place of residence and diagnosed diseases. The study employed an ad hoc questionnaire in a group of 300 inhabitants of Upper Silesia voivodship. Knowledge of functional food among the group covered in the study was far from satisfactory. The choice of functional food was of intuitive character. In addition, the group covered was more likely to choose pharmacotherapy instead of diet-related prevention then, which can be associated with presumption of too distant effects and a long period of treatment.

Keywords: consumer choice, functional food, healthy lifestyle, consumer knowledge

Procedia PDF Downloads 256
4750 A Study on the Pulse Transformer Design Considering Inrush Current in the Welding Machine

Authors: In-Gun Kim, Hyun-Seok Hong, Dong-Woo Kang, Ju Lee

Abstract:

An Inverter type arc-welding machine is inclined to be designed for higher frequency in order to reduce the size and cost. The need of the core material reconsideration for high frequency pulse transformer is more important since core loss grows as the frequency rises. An arc welding machine’s pulse transformer is designed using an Area Product (Ap) method and is considered margin air gap core design in order to prevent the burning of the IGBT by the inrush current. Finally, the reduction of the core weight and the core size are compared according to different materials for 30kW inverter type arc welding machine.

Keywords: pulse transformers, welding, inrush current, air gaps

Procedia PDF Downloads 459
4749 The Predictors of Head and Neck Cancer-Head and Neck Cancer-Related Lymphedema in Patients with Resected Advanced Head and Neck Cancer

Authors: Shu-Ching Chen, Li-Yun Lee

Abstract:

The purpose of the study was to identify the factors associated with head and neck cancer-related lymphoedema (HNCRL)-related symptoms, body image, and HNCRL-related functional outcomes among patients with resected advanced head and neck cancer. A cross-sectional correlational design was conducted to examine the predictors of HNCRL-related functional outcomes in patients with resected advanced head and neck cancer. Eligible patients were recruited from a single medical center in northern Taiwan. Consecutive patients were approached and recruited from the Radiation Head and Neck Outpatient Department of this medical center. Eligible subjects were assessed for the Symptom Distress Scale–Modified for Head and Neck Cancer (SDS-mhnc), Brief International Classification of Functioning, Disability and Health (ICF) Core Set for Head and Neck Cancer (BCSQ-H&N), Body Image Scale–Modified (BIS-m), The MD Anderson Head and Neck Lymphedema Rating Scale (MDAHNLRS), The Foldi’s Stages of Lymphedema (Foldi’s Scale), Patterson’s Scale, UCLA Shoulder Rating Scale (UCLA SRS), and Karnofsky’s Performance Status Index (KPS). The results showed that the worst problems with body HNCRL functional outcomes. Patients’ HNCRL symptom distress and performance status are robust predictors across over for overall HNCRL functional outcomes, problems with body HNCRL functional outcomes, and activity and social functioning HNCRL functional outcomes. Based on the results of this period research program, we will develop a Cancer Rehabilitation and Lymphedema Care Program (CRLCP) to use in the care of patients with resected advanced head and neck cancer.

Keywords: head and neck cancer, resected, lymphedema, symptom, body image, functional outcome

Procedia PDF Downloads 258
4748 The Effect of Honeycomb Core Thickness on the Repeated Low-Velocity Impact Behavior of Sandwich Beams

Authors: S. H. Abo Sabah, A. B. H. Kueh, M. A. Megat Johari, T. A. Majid

Abstract:

In a recent study, a new bio-inspired honeycomb sandwich beam (BHSB) mimicking the head configuration of the woodpecker was developed. The beam consists of two carbon/epoxy composite face sheets, aluminum honeycomb core, and rubber core to enhance the repeated low-velocity impact resistance of sandwich structures. This paper aims to numerically enhance the repeated low-velocity impact resistance of the BHSB via optimizing the aluminum honeycomb core thickness. The beam was investigated employing three core thicknesses: 20 mm, 25 mm, and 30 mm at three impact energy levels (13.5 J, 15.55 J, 21.43 J). The results revealed that increasing the thickness of the aluminum honeycomb core to a certain level enhances the sandwich beam stiffness. The beam with the 25 mm honeycomb core thickness was the only beam that can sustain five repeated impacts achieving the highest impact resistance efficiency index, especially at high energy levels. Furthermore, the bottom face sheet of this beam developed the lowest stresses indicating that this thickness has a relatively better performance during impact events since it allowed minimal stress to reach the bottom face sheet. Overall, increasing the aluminum core thickness will increase the height of its cells subjecting it to buckling phenomenon. Therefore, this study suggests that the optimal thickness of the aluminum honeycomb core should be 65 % of the overall thickness of the sandwich beam to have the best impact resistance.

Keywords: sandwich beams, core thickness, impact behavior, finite element analysis, modeling

Procedia PDF Downloads 153
4747 Synthesis of Nano Iron Copper Core-Shell by Using K-M Reactor

Authors: Mohamed Ahmed AbdelKawy, A. H. El-Shazly

Abstract:

In this study, Nano iron-copper core-shell was synthesized by using Kinetic energy micro reactor ( K-M reactor). The reaction between nano-pure iron with copper sulphate pentahydrate (CuSO4.5H2O) beside NaCMC as a stabilizer at K-M reactor gives many advantages in comparison with the traditional chemical method for production of nano iron-Copper core-shell in batch reactor. Many factors were investigated for its effect on the process performance such as initial concentrations of nano iron and copper sulphate pentahydrate solution. Different techniques were used for investigation and characterization of the produced nano iron particles such as SEM, XRD, UV-Vis, XPS, TEM and PSD. The produced Nano iron-copper core-shell particle using micro mixer showed better characteristics than those produced using batch reactor in different aspects such as homogeneity of the produced particles, particle size distribution and size, as core diameter 10nm particle size were obtained. The results showed that 10 nm core diameter were obtained using Micro mixer as compared to 80 nm core diameter in one-fourth the time required by using traditional batch reactor and high thickness of copper shell and good stability.

Keywords: nano iron, core-shell, reduction reaction, K-M reactor

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4746 Phase Transition in Iron Storage Protein Ferritin

Authors: Navneet Kaur, S. D. Tiwari

Abstract:

Ferritin is a protein which present in the blood of mammals. It maintains the need of iron inside the body. It has an antiferromagnetic iron core, 7-8 nm in size, which is encapsulated inside a protein cage. The thickness of this protein shell is about 2-3 nm. This protein shell reduces the interaction among particles and make ferritin a model superparamagnet. The major composition of ferritin core is mineral ferrihydrite. The molecular formula of ferritin core is (FeOOH)8[FeOOPO3H2]. In this study, we discuss the phase transition of ferritin. We characterized ferritin using x-ray diffractometer, transmission electron micrograph, thermogravimetric analyzer and vibrating sample magnetometer. It is found that ferritin core is amorphous in nature with average particle size of 8 nm. The thermogravimetric and differential thermogravimetric analysis curves shows mass loss at different temperatures. We heated ferritin at these temperatures. It is found that ferritin core starts decomposing after 390^o C. At 1020^o C, the ferritin core is finally converted to alpha phase of iron oxide. Magnetization behavior of final sample clearly shows the iron oxyhydroxide core is completely converted to alpha iron oxide.

Keywords: Antiferromagnetic, Ferritin, Phase, Superparamagnetic

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4745 Investigating what Effects Aviation Fluids Have on the Flatwise Compressive Strength of Nomex® Honeycomb Core Material

Authors: G. Kim, R. Sterkenburg

Abstract:

One of the disadvantages of honeycomb sandwich structure is that they are prone to fluid intrusion. The purpose of this study is to determine if the structural properties of honeycomb core are affected by contact with a fluid. The test specimens were manufactured of fiberglass prepreg for the facesheets and Nomex® honeycomb core for the core material in accordance with ASTM C-365/365M. Test specimens were soaked in several different kinds of fluids, such as aircraft fuel, turbine engine oil, hydraulic fluid, and water for a period of 60 days. A flatwise compressive test was performed, and the test results were analyzed to determine how the contact with aircraft fluids affected the compressive strength of the Nomex® honeycomb core and how the strength was recovered when the specimens were dry. In addition, the investigation of de-bonding between facesheet and core material after soaking were performed to support the study.

Keywords: sandwich structure, honeycomb, environmental degradation, debonding

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4744 Monotonicity of the Jensen Functional for f-Divergences via the Zipf-Mandelbrot Law

Authors: Neda Lovričević, Đilda Pečarić, Josip Pečarić

Abstract:

The Jensen functional in its discrete form is brought in relation to the Csiszar divergence functional, this time via its monotonicity property. This approach presents a generalization of the previously obtained results that made use of interpolating Jensen-type inequalities. Thus the monotonicity property is integrated with the Zipf-Mandelbrot law and applied to f-divergences for probability distributions that originate from the Csiszar divergence functional: Kullback-Leibler divergence, Hellinger distance, Bhattacharyya distance, chi-square divergence, total variation distance. The Zipf-Mandelbrot and the Zipf law are widely used in various scientific fields and interdisciplinary and here the focus is on the aspect of the mathematical inequalities.

Keywords: Jensen functional, monotonicity, Csiszar divergence functional, f-divergences, Zipf-Mandelbrot law

Procedia PDF Downloads 142
4743 On Compression Properties of Honeycomb Structures Using Flax/PLA Composite as Core Material

Authors: S. Alsubari, M. Y. M. Zuhri, S. M. Sapuan, M. R. Ishaks

Abstract:

Sandwich structures based on cellular cores are increasingly being utilized as energy-absorbing components in the industry. However, determining ideal structural configurations remains challenging. This chapter compares the compression properties of flax fiber-reinforced polylactic acid (PLA) of empty honeycomb core, foam-filled honeycomb and double cell wall square interlocking core sandwich structure under quasi-static compression loading. The square interlocking core is fabricated through a slotting technique, whereas the honeycomb core is made using a corrugated mold that was initially used to create the corrugated core composite profile, which is then cut into corrugated webs and assembled to form the honeycomb core. The sandwich structures are tested at a crosshead displacement rate of 2 mm/min. The experimental results showed that honeycomb outperformed the square interlocking core in terms of their strength capability and SEA by around 14% and 34%, respectively. It is observed that the foam-filled honeycomb collapse in a progressive mode, exhibiting noticeable advantages over the empty honeycomb; this is attributed to the interaction between the honeycomb wall and foam filler. Interestingly, the average SEAs of foam-filled and empty honeycomb cores have no significant difference, around 8.7kJ/kg and 8.2kJ/kg, respectively. In contrast, its strength capability is clearly pronounced, in which the foam-filled core outperforms the empty counterparts by around 33%. Finally, the results for empty and foam-filled cores were significantly superior to aluminum cores published in the literature.

Keywords: compressive strength, flax, honeycomb core, specific energy absorption

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4742 Diagnostic Accuracy Of Core Biopsy In Patients Presenting With Axillary Lymphadenopathy And Suspected Non-Breast Malignancy

Authors: Monisha Edirisooriya, Wilma Jack, Dominique Twelves, Jennifer Royds, Fiona Scott, Nicola Mason, Arran Turnbull, J. Michael Dixon

Abstract:

Introduction: Excision biopsy has been the investigation of choice for patients presenting with pathological axillary lymphadenopathy without a breast abnormality. Core biopsy of nodes can provide sufficient tissue for diagnosis and has advantages in terms of morbidity and speed of diagnosis. This study evaluates the diagnostic accuracy of core biopsy in patients presenting with axillary lymphadenopathy. Methods: Between 2009 and 2019, 165 patients referred to the Edinburgh Breast Unit had a total of 179 axillary lymph node core biopsies. Results: 152 (92%) of the 165 initial core biopsies were deemed to contain adequate nodal tissue. Core biopsy correctly established malignancy in 75 of the 78 patients with haematological malignancy (96%) and in all 28 patients with metastatic carcinoma (100%) and correctly diagnosed benign changes in 49 of 57 (86%) patients with benign conditions. There were no false positives and no false negatives. In 67 (85.9%) of the 78 patients with hematological malignancy, there was sufficient material in the first core biopsy to allow the pathologist to make an actionable diagnosis and not ask for more tissue sampling prior to treatment. There were no complications of core biopsy. On follow up, none of the patients with benign cores has been shown to have malignancy in the axilla and none with lymphoma had their initial disease incorrectly classified. Conclusions: This study shows that core biopsy is now the investigation of choice for patients presenting with axillary lymphadenopathy even in those suspected as having lymphoma.

Keywords: core biopsy, excision biopsy, axillary lymphadenopathy, non-breast malignancy

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4741 Natural Emergence of a Core Structure in Networks via Clique Percolation

Authors: A. Melka, N. Slater, A. Mualem, Y. Louzoun

Abstract:

Networks are often presented as containing a “core” and a “periphery.” The existence of a core suggests that some vertices are central and form the skeleton of the network, to which all other vertices are connected. An alternative view of graphs is through communities. Multiple measures have been proposed for dense communities in graphs, the most classical being k-cliques, k-cores, and k-plexes, all presenting groups of tightly connected vertices. We here show that the edge number thresholds for such communities to emerge and for their percolation into a single dense connectivity component are very close, in all networks studied. These percolating cliques produce a natural core and periphery structure. This result is generic and is tested in configuration models and in real-world networks. This is also true for k-cores and k-plexes. Thus, the emergence of this connectedness among communities leading to a core is not dependent on some specific mechanism but a direct result of the natural percolation of dense communities.

Keywords: cliques, core structure, percolation, phase transition

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4740 Functional Dyspepsia and Irritable Bowel Syndrome: Life sketches of Functional Illnesses (Non-Organic) in West Bengal, India

Authors: Urmita Chakraborty

Abstract:

To start with, Organic Illnesses are no longer considered as only health difficulties. Functional Illnesses that are emotional in origin have become the search areas in many investigations. In the present study, an attempt has made to study the psychological nature of Functional Gastro-Intestinal Disorders (FGID) in West Bengal. In the specialty of Gastroenterology, the medically unexplained symptom-based conditions are known as Functional Gastrointestinal Disorder (FGID). In the present study, Functional Dyspepsia (FD) and Irritable Bowel Syndrome (IBS) have been taken for investigations. 72 cases have been discussed in this context. Results of the investigation have been analyzed in terms of a qualitative framework. Theoretical concepts on persistent thoughts and behaviors will be delineated in the analysis. Processes of self-categorization will be implemented too. Aspects of Attachments and controlling of affect as well as meta-cognitive appraisals are further considered for the depiction.

Keywords: functional dyspepsia, irritable bowel syndrome, self-categorization

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4739 Social Discussion Networks during the Covid-19 Pandemic: A Study of College Students Core Discussion Groups

Authors: Regan Harper, Song Yang, Douglas Adams

Abstract:

During the historically unprecedent time of Covid-19 pandemic, we survey college students with social issue generators to measure their core discussion groups. For the total 191 students, we elicit 847 conversation partners (alters) with our five social issue generators such as school closing, facemasks, collegiate sports, race and policing, and social inequality, producing an average of 4.43 alters per respondent. The core discussion groups of our sample are very gender balanced, with female alters slightly outnumbering male alters. However, the core discussion groups are racially homogenous, consisting of mostly white students (around or above 80 percent). Explanatory analyses reveal that gender and race of respondents significantly impact the size, gender composition, and racial composition of their core discussion networks. We discuss those major findings and implications of future studies in our conclusion section.

Keywords: core discussion groups, social issue generators, ego-centric network, Covid-19 pandemic

Procedia PDF Downloads 91