Search results for: degree%20of%20dilution
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2688

Search results for: degree%20of%20dilution

2238 Study of Nucleation and Growth Processes of Ettringite in Supersaturated Diluted Solutions

Authors: E. Poupelloz, S. Gauffinet

Abstract:

Ettringite Ca₆Al₂(SO₄)₃(OH)₁₂26H₂O is one of the major hydrates formed during cement hydration. Ettringite forms in Portland cement from the reaction between tricalcium aluminate Ca₃Al₂O₆ and calcium sulfate. Ettringite is also present in calcium sulfoaluminate cement in which it is the major hydrate, formed by the reaction between yeelimite Ca₄(AlO₂)₆SO₄ and calcium sulfate. About the formation of ettringite, numerous results are available in the literature even if some issues are still under discussion. However, almost all published work about ettringite was done on cementitious systems. Yet in cement, hydration reactions are very complex, the result of dissolution-precipitation processes and are submitted to various interactions. Understanding the formation process of a phase alone, here ettringite, is the first step to later understand the much more complex reactions happening in cement. This study is crucial for the comprehension of early cement hydration and physical behavior. Indeed formation of hydrates, in particular, ettringite, will have an influence on the rheological properties of the cement paste and on the need for admixtures. To make progress toward the understanding of existing phenomena, a specific study of nucleation and growth processes of ettringite was conducted. First ettringite nucleation was studied in ionic aqueous solutions, with controlled but different experimental conditions, as different supersaturation degrees (β), different pH or presence of exogenous ions. Through induction time measurements, interfacial ettringite crystals solution energies (γ) were determined. Growth of ettringite in supersaturated solutions was also studied through chain crystallization reactions. Specific BET surface area measurements and Scanning Electron Microscopy observations seemed to prove that growth process is favored over the nucleation process when ettringite crystals are initially present in a solution with a low supersaturation degree. The influence of stirring on ettringite formation was also investigated. Observation was made that intensity and nature of stirring have a high influence on the size of ettringite needles formed. Needle sizes vary from less than 10µm long depending on the stirring to almost 100µm long without any stirring. During all previously mentioned experiments, initially present ions are consumed to form ettringite in such a way that the supersaturation degree with regard to ettringite is decreasing over time. To avoid this phenomenon a device compensating the drop of ion concentrations by adding some more solutions, and therefore always have constant ionic concentrations, was used. This constant β recreates the conditions of the beginning of cement paste hydration, when the dissolution of solid reagents compensates the consumption of ions to form hydrates. This device allowed the determination of the ettringite precipitation rate as a function of the supersaturation degree β. Taking samples at different time during ettringite precipitation and doing BET measurements allowed the determination of the interfacial growth rate of ettringite in m²/s. This work will lead to a better understanding and control of ettringite formation alone and thus during cements hydration. This study will also ultimately define the impact of ettringite formation process on the rheology of cement pastes at early age, which is a crucial parameter from a practical point of view.

Keywords: cement hydration, ettringite, morphology of crystals, nucleation-growth process

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2237 Hidden Hot Spots: Identifying and Understanding the Spatial Distribution of Crime

Authors: Lauren C. Porter, Andrew Curtis, Eric Jefferis, Susanne Mitchell

Abstract:

A wealth of research has been generated examining the variation in crime across neighborhoods. However, there is also a striking degree of crime concentration within neighborhoods. A number of studies show that a small percentage of street segments, intersections, or addresses account for a large portion of crime. Not surprisingly, a focus on these crime hot spots can be an effective strategy for reducing community level crime and related ills, such as health problems. However, research is also limited in an important respect. Studies tend to use official data to identify hot spots, such as 911 calls or calls for service. While the use of call data may be more representative of the actual level and distribution of crime than some other official measures (e.g. arrest data), call data still suffer from the 'dark figure of crime.' That is, there is most certainly a degree of error between crimes that occur versus crimes that are reported to the police. In this study, we present an alternative method of identifying crime hot spots, that does not rely on official data. In doing so, we highlight the potential utility of neighborhood-insiders to identify and understand crime dynamics within geographic spaces. Specifically, we use spatial video and geo-narratives to record the crime insights of 36 police, ex-offenders, and residents of a high crime neighborhood in northeast Ohio. Spatial mentions of crime are mapped to identify participant-identified hot spots, and these are juxtaposed with calls for service (CFS) data. While there are bound to be differences between these two sources of data, we find that one location, in particular, a corner store, emerges as a hot spot for all three groups of participants. Yet it does not emerge when we examine CFS data. A closer examination of the space around this corner store and a qualitative analysis of narrative data reveal important clues as to why this store may indeed be a hot spot, but not generate disproportionate calls to the police. In short, our results suggest that researchers who rely solely on official data to study crime hot spots may risk missing some of the most dangerous places.

Keywords: crime, narrative, video, neighborhood

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2236 Behavioral Analysis of Anomalies in Intertemporal Choices Through the Concept of Impatience and Customized Strategies for Four Behavioral Investor Profiles With an Application of the Analytic Hierarchy Process: A Case Study

Authors: Roberta Martino, Viviana Ventre

Abstract:

The Discounted Utility Model is the essential reference for calculating the utility of intertemporal prospects. According to this model, the value assigned to an outcome is the smaller the greater the distance between the moment in which the choice is made and the instant in which the outcome is perceived. This diminution determines the intertemporal preferences of the individual, the psychological significance of which is encapsulated in the discount rate. The classic model provides a discount rate of linear or exponential nature, necessary for temporally consistent preferences. Empirical evidence, however, has proven that individuals apply discount rates with a hyperbolic nature generating the phenomenon of intemporal inconsistency. What this means is that individuals have difficulty managing their money and future. Behavioral finance, which analyzes the investor's attitude through cognitive psychology, has made it possible to understand that beyond individual financial competence, there are factors that condition choices because they alter the decision-making process: behavioral bias. Since such cognitive biases are inevitable, to improve the quality of choices, research has focused on a personalized approach to strategies that combines behavioral finance with personality theory. From the considerations, it emerges the need to find a procedure to construct the personalized strategies that consider the personal characteristics of the client, such as age or gender, and his personality. The work is developed in three parts. The first part discusses and investigates the weight of the degree of impatience and impatience decrease in the anomalies of the discounted utility model. Specifically, the degree of decrease in impatience quantifies the impact that emotional factors generated by haste and financial market agitation have on decision making. The second part considers the relationship between decision making and personality theory. Specifically, four behavioral categories associated with four categories of behavioral investors are considered. This association allows us to interpret intertemporal choice as a combination of bias and temperament. The third part of the paper presents a method for constructing personalized strategies using Analytic Hierarchy Process. Briefly: the first level of the analytic hierarchy process considers the goal of the strategic plan; the second level considers the four temperaments; the third level compares the temperaments with the anomalies of the discounted utility model; and the fourth level contains the different possible alternatives to be selected. The weights of the hierarchy between level 2 and level 3 are constructed considering the degrees of decrease in impatience derived for each temperament with an experimental phase. The results obtained confirm the relationship between temperaments and anomalies through the degree of decrease in impatience and highlight that the actual impact of emotions in decision making. Moreover, it proposes an original and useful way to improve financial advice. Inclusion of additional levels in the Analytic Hierarchy Process can further improve strategic personalization.

Keywords: analytic hierarchy process, behavioral finance anomalies, intertemporal choice, personalized strategies

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2235 The Development of Quality Standards for the Qualification of Community Interpreters in Germany: A Needs Assessment

Authors: Jessica Terese Mueller, Christoph Breitsprecher, Mike Oliver Mosko

Abstract:

Due to an unusually high number of asylum seekers entering Germany over the course of the past few years, the need for community interpreters has increased dramatically, in order to make the communication between asylum seekers and various actors in social and governmental agencies possible. In the field of social work in particular, there are community interpreters who possess a wide spectrum of qualifications spanning from state-certified professional interpreters with graduate degrees to lay or ad-hoc interpreters with little to no formal training. To the best of our knowledge, Germany has no official national quality standards for the training of community interpreters at present, which would serve to professionalise this field as well as to assure a certain degree of quality in the training programmes offered. Given the current demand for trained community interpreters, there is a growing number of training programmes geared toward qualifying community interpreters who work with asylum seekers in Germany. These training programmes range from short one-day workshops to graduate programmes with specialisations in Community Interpreting. As part of a larger project to develop quality standards for the qualification of community interpreters working with asylum seekers in the field of social work, a needs assessment was performed in the city-state of Hamburg and the state of North Rhine Westphalia in the form of focus groups and individual interviews with relevant actors in the field in order to determine the content and practical knowledge needed for community interpreters from the perspectives of those who work in and rely on this field. More specifically, social workers, volunteers, certified language and cultural mediators, paid and volunteer community interpreters and asylum seekers were invited to take part in focus groups in both locations, and asylum seekers, training providers, researchers, linguists and other national and international experts were individually interviewed. The responses collected in these focus groups and interviews have been analysed using Mayring’s concept of content analysis. In general, the responses indicate a high degree of overlap related to certain categories as well as some categories which seemed to be of particular importance to certain groups individually, while showing little to no relevance for other groups. For example, the topics of accuracy and transparency of the interpretations, as well as professionalism and ethical concerns were touched on in some form in most groups. Some group-specific topics which are the focus of experts were topics related to interpreting techniques and more concretely described theoretical and practical knowledge which should be covered in training programmes. Social workers and volunteers generally concentrated on issues regarding the role of the community interpreters and the importance of setting and clarifying professional boundaries. From the perspective of service receivers, asylum seekers tended to focus on the importance of having access to interpreters who are from their home region or country and who speak the same regiolect, dialect or variety as they do in order to prevent misunderstandings or misinterpretations which might negatively affect their asylum status. These results indicate a certain degree of consensus with trainings offered internationally for community interpreters.

Keywords: asylum seekers, community interpreting, needs assessment, quality standards, training

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2234 The Effect of the Pronunciation of Emphatic Sounds on Perceived Masculinity/Femininity

Authors: M. Sayyour, M. Abdulkareem, O. Osman, S. Salmeh

Abstract:

Emphatic sounds in Arabic are /tˤ/, /sˤ/, /dˤ/, and /ðˤ/. They involve a secondary articulation in the pharynx area as opposed to their counterparts: /t/,/s/,/d/and /ð/. Although they are present in most Arabic dialects, some dialects have lost this class as a historical development, such as Maltese Arabic. It has been found that there is a difference in the pronunciation of these emphatic sounds between the two genders, arguing that males tend to produce more evident emphasis than females. This study builds on these studies by trying to investigate whether listeners perceive fully emphatic sounds as more masculine and less emphatic sounds as more feminine. Furthermore, the study aims to find out which is more important in this perception process: the emphatic consonant itself or the vowel following it. To test this, natural and manipulated tokens of two male and two female speakers were used. The natural tokens include words that have emphatic consonant and emphatic vowel and tokens that have plain consonant and plain vowel. The manipulated tokens include words that have emphatic consonant but central vowel and plain consonant followed by the same central vowel. These manipulated tokens allow us to see whether the consonant will still affect the perception even if the vowel is controlled. Another group of words that contained no emphatic sounds was used as a control group. The total number of tokens (natural, manipulated, and control) are 160 tokens. After that, 60 university students (30 males and 30 females) listened to these tokens and responded by choosing a specific character that they think is likely to produce each token. The characters’ descriptions are carefully written with two degrees of femininity and two degrees of masculinity. The preliminary results for the femininity level showed that the highest degree of femininity was for tokens that contain a plain consonant and a plain vowel. The lowest level of femininity was given for tokens that have fully emphatic consonant and vowel. For the manipulated tokens that contained plain consonant and central vowel, the femininity degree was high which indicates that the consonant is more important than the vowel, while for the manipulated tokens that contain emphatic consonant and a central vowel, the femininity level was higher than that for the tokens that have emphatic consonant and emphatic vowel, which indicates that the vowel is more important for the perception of emphatic consonants. These results are interpreted in light of feminist linguistic theories, linguistic expectations, performed gender and linguistic change theories.

Keywords: Emphatic sounds, gender studies, perception, sociophonetics

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2233 Using Geographic Information System and Analytic Hierarchy Process for Detecting Forest Degradation in Benslimane Forest, Morocco

Authors: Loubna Khalile, Hicham Lahlaoi, Hassan Rhinane, A. Kaoukaya, S. Fal

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Green spaces is an essential element, they contribute to improving the quality of lives of the towns around them. They are a place of relaxation, walk and rest a playground for sport and youths. According to United Nations Organization Forests cover 31% of the land. In Morocco in 2013 that cover 12.65 % of the total land area, still, a small proportion compared to the natural needs of forests as a green lung of our planet. The Benslimane Forest is a large green area It belongs to Chaouia-Ouardigha Region and Greater Casablanca Region, it is located geographically between Casablanca is considered the economic and business Capital of Morocco and Rabat the national political capital, with an area of 12261.80 Hectares. The essential problem usually encountered in suburban forests, is visitation and tourism pressure it is anthropogenic actions, as well as other ecological and environmental factors. In recent decades, Morocco has experienced a drought year that has influenced the forest with increasing human pressure and every day it suffers heavy losses, as well as over-exploitation. The Moroccan forest ecosystems are weak with intense ecological variation, domanial and imposed usage rights granted to the population; forests are experiencing a significant deterioration due to forgetfulness and immoderate use of forest resources which can influence the destruction of animal habitats, vegetation, water cycle and climate. The purpose of this study is to make a model of the degree of degradation of the forest and know the causes for prevention by using remote sensing and geographic information systems by introducing climate and ancillary data. Analytic hierarchy process was used to find out the degree of influence and the weight of each parameter, in this case, it is found that anthropogenic activities have a fairly significant impact has thus influenced the climate.

Keywords: analytic hierarchy process, degradation, forest, geographic information system

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2232 Parametric Studies of Ethylene Dichloride Purification Process

Authors: Sh. Arzani, H. Kazemi Esfeh, Y. Galeh Zadeh, V. Akbari

Abstract:

Ethylene dichloride is a colorless liquid with a smell like chloroform. EDC is classified in the simple hydrocarbon group which is obtained from chlorinating ethylene gas. Its chemical formula is C2H2Cl2 which is used as the main mediator in VCM production. Therefore, the purification process of EDC is important in the petrochemical process. In this study, the purification unit of EDC was simulated, and then validation was performed. Finally, the impact of process parameter was studied for the degree of EDC purity. The results showed that by increasing the feed flow, the reflux impure combinations increase and result in an EDC purity decrease.

Keywords: ethylene dichloride, purification, edc, simulation

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2231 An Inquiry on 2-Mass and Wheeled Mobile Robot Dynamics

Authors: Boguslaw Schreyer

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In this paper, a general dynamical model is derived using the Lagrange formalism. The two masses: sprang and unsprang are included in a six-degree of freedom model for a sprung mass. The unsprung mass is included and shown only in a simplified model, although its equations have also been derived by an author. The simplified equations, more suitable for the computer model of robot’s dynamics are also shown.

Keywords: dynamics, mobile, robot, wheeled mobile robots

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2230 Charged Amphiphilic Polypeptide Based Micelle Hydrogel Composite for Dual Drug Release

Authors: Monika Patel, Kazuaki Matsumura

Abstract:

Synthetic hydrogels, with their unique properties such as porosity, strength, and swelling in aqueous environment, are being used in many fields from food additives to regenerative medicines, from diagnostic and pharmaceuticals to drug delivery systems (DDS). But, hydrogels also have some limitations in terms of homogeneity of drug distribution and quantity of loaded drugs. As an alternate, polymeric micelles are extensively used as DDS. With the ease of self-assembly, and distinct stability they remarkably improve the solubility of hydrophobic drugs. However, presently, combinational therapy is the need of time and so are systems which are capable of releasing more than one drug. And it is one of the major challenges towards DDS to control the release of each drug independently, which simple DDS cannot meet. In this work, we present an amphiphilic polypeptide based micelle hydrogel composite to study the dual drug release for wound healing purposes using Amphotericin B (AmpB) and Curcumin as model drugs. Firstly, two differently charged amphiphilic polypeptide chains were prepared namely, poly L-Lysine-b-poly phenyl alanine (PLL-PPA) and poly Glutamic acid-b-poly phenyl alanine (PGA-PPA) through ring opening polymerization of amino acid N-carboxyanhydride. These polymers readily self-assemble to form micelles with hydrophobic PPA block as core and hydrophilic PLL/PGA as shell with an average diameter of about 280nm. The thus formed micelles were loaded with the model drugs. The PLL-PPA micelle was loaded with curcumin and PGA-PPA was loaded with AmpB by dialysis method. Drug loaded micelles showed a slight increase in the mean diameter and were fairly stable in solution and lyophilized forms. For forming the micelles hydrogel composite, the drug loaded micelles were dissolved and were cross linked using genipin. Genipin uses the free –NH2 groups in the PLL-PPA micelles to form a hydrogel network with free PGA-PPA micelles trapped in between the 3D scaffold formed. Different composites were tested by changing the weight ratios of the both micelles and were seen to alter its resulting surface charge from positive to negative with increase in PGA-PPA ratio. The composites with high surface charge showed a burst release of drug in initial phase, were as the composites with relatively low net charge showed a sustained release. Thus the resultant surface charge of the composite can be tuned to tune its drug release profile. Also, while studying the degree of cross linking among the PLL-PPA particles for effect on dual drug release, it was seen that as the degree of crosslinking increases, an increase in the tendency to burst release the drug (AmpB) is seen in PGA-PPA particle, were as on the contrary the PLL-PPA particles showed a slower release of Curcumin with increasing the cross linking density. Thus, two different pharmacokinetic profile of drugs were seen by changing the cross linking degree. In conclusion, a unique charged amphiphilic polypeptide based micelle hydrogel composite for dual drug delivery. This composite can be finely tuned on the basis of need of drug release profiles by changing simple parameters such as composition, cross linking and pH.

Keywords: amphiphilic polypeptide, dual drug release, micelle hydrogel composite, tunable DDS

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2229 One Pot Synthesis of Ultrasmall NiMo Catalysts Supported on Amorphous Alumina with Enhanced type 2 Sites for Hydrodesulfurization Reaction: A Combined Experimental and Theoretical Study

Authors: Shalini Arora, Sri Sivakumar

Abstract:

The deep removal of high molecular weight sulphur compounds (e.g., 4,6, dimethyl dibenzothiophene) is challenging due to their steric hindrance. Hydrogenation desulfurization (HYD) pathway is the main pathway to remove these sulfur compounds, and it is mainly governed by the number of type 2 sites. The formation of type 2 sites can be enhanced by modulating the pore structure and the interaction between the active metal and support. To this end, we report the enhanced HDS catalytic activity of ultrasmall NiMo supported on amorphous alumina (A-Al₂O₃) catalysts by one pot colloidal synthesis method followed by calcination and sulfidation. The amorphous alumina (A-Al₂O₃) was chosen as the support due to its lower surface energy, better physicochemical properties, and enhanced acidic sites (due to the dominance of tetra and penta coordinated [Al] sites) than crystalline alumina phase. At 20% metal oxide composition, NiMo supported on A-Al₂O₃ catalyst showed 1.4 and 1.2 times more reaction rate constant and turn over frequency (TOF) respectively than the conventional catalyst (wet impregnated NiMo catalysts) for HDS reaction of dibenzothiophene reactant molecule. A-Al₂O₃ supported catalysts represented enhanced type 2 sites formation (because this catalystpossesses higher sulfidation degree (80%) and NiMoS sites (19.3 x 10¹⁷ sites/mg) with desired optimum stacking degree (2.5) than wet impregnated catalyst at same metal oxide composition 20%) along with higher active metal dispersion, Mo edge site fraction. The experimental observations were also supported by DFT simulations. Lower heat of adsorption (< 4.2 ev for MoS2 interaction and < 3.15 ev for Ni doped MoS2 interaction) values for A-Al₂O₃ confirmed the presence of weaker metal-support interaction in A-Al₂O₃ in contrast to crystalline ℽ-Al₂O3. The weak metal-support interaction for prepared catalysts clearly suggests the higher formation of type 2 sites which leads to higher catalytic activity for HDS reaction.

Keywords: amorphous alumina, colloidal, desulfurization, metal-support interaction

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2228 Cellulose Extraction from Pomelo Peel: Synthesis of Carboxymethyl Cellulose

Authors: Jitlada Chumee, Drenpen Seeburin

Abstract:

The cellulose was extracted from pomelo peel and an etherification reaction used for converting cellulose to carboxymethyl cellulose (CMC). The pomelo peel was refluxed with 0.5 M HCl and 1 M NaOH solution at 90°C for 1 h and 2 h, respectively. The cellulose was bleached with calcium hypochlorite and used as precursor. The precursor was soaked in mixed solution between isopropyl alcohol and 40%w/v NaOH for 12 h. After that, chloroacetic acid was added and reacted at 55°C for 6 h. The optimum condition was 5 g of cellulose: 0.25 mole of NaOH : 0.07 mole of ClCH2COOH with 78.00% of yield. Moreover, the product had 0.54 of degree of substitution (DS).

Keywords: pomelo peel, carboxymethyl cellulose, bioplastic, extraction

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2227 Integer Programming-Based Generation of Difficulty Level for a Racing Game

Authors: Sangchul Kim, Dosaeng Park

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It is one of the important design issues to provide various levels of difficulty in order to suit the skillfulness of an individual. In this paper we propose an integer programming-based method for selecting a mixture of challenges for a racing game that meet a given degree of difficulty. The proposed method can also be used to dynamically adjust the difficulty of the game during the progression of playing. By experiments, it is shown that our method performs well enough to generate games with various degrees of difficulty that match the perception of players.

Keywords: level generation, level adjustment, racing game, ip

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2226 Chebyshev Polynomials Relad with Fibonacci and Lucas Polynomials

Authors: Vandana N. Purav

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Fibonacci and Lucas polynomials are special cases of Chebyshev polynomial. There are two types of Chebyshev polynomials, a Chebyshev polynomial of first kind and a Chebyshev polynomial of second kind. Chebyshev polynomial of second kind can be derived from the Chebyshev polynomial of first kind. Chebyshev polynomial is a polynomial of degree n and satisfies a second order homogenous differential equation. We consider the difference equations which are related with Chebyshev, Fibonacci and Lucas polynomias. Thus Chebyshev polynomial of second kind play an important role in finding the recurrence relations with Fibonacci and Lucas polynomials.

Keywords:

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2225 Modified Fractional Curl Operator

Authors: Rawhy Ismail

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Applying fractional calculus in the field of electromagnetics shows significant results. The fractionalization of the conventional curl operator leads to having additional solutions to an electromagnetic problem. This work restudies the concept of the fractional curl operator considering fractional time derivatives in Maxwell’s curl equations. In that sense, a general scheme for the wave loss term is introduced and the degree of freedom of the system is affected through imposing the new fractional parameters. The conventional case is recovered by setting all fractional derivatives to unity.

Keywords: curl operator, fractional calculus, fractional curl operators, Maxwell equations

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2224 Proposed Pattern for Fitted Men's Suit Jacket Using the Method of Draping on the Mannequin

Authors: Hazem A. Abdelfattah, Salia H. Khafaji

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Apparel industry needs to direct scientific researches to develop it , and because of the importance of a men’s suit jacket industry, the study of the basics of men’s jacket pattern making requires a high degree of accuracy and efficiency which contain a lot of technical and skill aspects to give the jacket a drape, comfort and good fitting , prompting researchers to think about the use of men’s mannequin with sizes (M-L-XL) to devise a method to draft a paper pattern for the men's suit jacket to use it in the industry easily and quickly and achieve the required good fitting.

Keywords: draping, pattern, men, jacket

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2223 Critical Thinking in the Moroccan Textbooks of English: Ticket to English as a Case Study

Authors: Mohsine Jebbour

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The ultimate aim of this study was to analyze a second-year baccalaureate textbook of English to see to what extent it includes elements of critical thinking. A further purpose was to assess the extent to which the teachers’ teaching practices help students develop some degree of critical thinking. The literature on critical thinking indicated that all the writers agree that critical thinking is skilled and dispositional oriented, and most of the definitions highlight the skill and disposition to select, collect, analyze and evaluate information effectively. In this study, two instruments were used, namely content analysis and questionnaire to ensure validity and reliability. The sample of this study, on the one hand, was a second year textbook of English, namely Ticket to English. The process of collecting data was carried out through designing a checklist to analyze the textbook of English. On the other hand, high school students (second baccalaureate grade) and teachers of English constituted the second sample. Two questionnaires were administered—One was completed by 28 high school teachers (18 males and10 females), and the other was completed by 51 students (26 males and 25 females) from Fez, Morocco. The items of the questionnaire tended to elicit both qualitative and quantitative data. An attempt was made to answer two research questions. One pertained to the extent to which the textbooks of English contain critical thinking elements (Critical thinking skills and dispositions, types of questions, language learning strategies, classroom activities); the second was concerned with whether the teaching practices of teachers of English help improve students’ critical thinking. The results demonstrated that the textbooks of English include elements of critical thinking, and the teachers’ teaching practices help the students develop some degree of critical thinking. Yet, the textbooks do not include problem-solving activities and media analysis and 86% of the teacher-respondents tended to skip activities in the textbooks, mainly the units dealing with Project Work and Study Skills which are necessary for enhancing critical thinking among the students. Therefore, the textbooks need to be designed around additional activities and the teachers are required to cover the units skipped so as to make the teaching of critical thinking effective.

Keywords: critical thinking, language learning strategies, language proficiency, teaching practices

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2222 An Empirical Study of Performance Management System: Implementation of Performance Management Cycle to Achieve High-Performance Culture at Pertamina Company, Indonesia

Authors: Arif Budiman

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Any organization or company that wishes to achieve vision, mission, and goals of the organization is required to implement a performance management system or known as the Performance Management System (PMS) in every part of the whole organization. PMS is a tool to help visualize the direction and work program of the organization to achieve the goal. The challenge is PMS should not stop merely as a visualization tool to achieve the vision and mission of the organization, but PMS should also be able to create a high-performance culture that is inherent in each individual of the organization. Establishment of a culture within an organization requires the support of top leaders and also requires a system or governance that encourages every individual in the organization to be involved in any work program of the organization. Keywords of creating a high-performance culture are the formation of communication pattern involving the whole individual, either vertically or horizontally, and performed consistently and persistently by all individuals in each line of the organization. PT Pertamina (Persero) as the state-owned national energy company holds a system to internalize the culture of high performance through a system called Performance Management System Cycle (PMS Cycle). This system has 7 stages of the cycle, those are: (1) defining vision, mission and strategic plan of the company, (2) defining key performance indicator of each line and the individual (‘expectation setting conversation’), (3) defining performance target and performance agreement, (4) monitoring performance on a monthly regular basis (‘pulse check’), (5) implementing performance dialogue between leaders and staffs periodically every 3 months (‘performance dialogue’), (6) defining rewards and consequences based on the achievement of the performance of each line and the individual, and (7) calculating the final performance value achieved by each line and individual from one period of the current year. Perform PMS is a continual communication running throughout the year, that is why any three performance discussion that should be performed, include expectation setting conversations, pulse check and performance dialogue. In addition, another significant point and necessary undertaken to complete the assessment of individual performance assessment is soft competencies through 360-degree assessment by leaders, staffs, and peers.

Keywords: 360-degree assessment, expectation setting conversation, performance management system cycle, performance dialogue, pulse check

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2221 Candida antartica Lipase Assisted Enrichment of n-3 PUFA in Indian Sardine Oil

Authors: Prasanna Belur, P. R. Ashwini, Sampath Charanyaa, I. Regupathi

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Indian oil sardine (Sardinella longiceps) are one of the richest and cheapest sources of n-3 polyunsaturated fatty acids (n-3 PUFA) such as Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA). The health benefits conferred by n-3 PUFA upon consumption, in the prevention and treatment of coronary, neuromuscular, immunological disorders and allergic conditions are well documented. Natural refined Indian Sardine oil generally contain about 25% (w/w) n-3 PUFA along with various unsaturated and saturated fatty acids in the form of mono, di, and triglycerides. Having high concentration of n-3 PUFA content in the glyceride form is most desirable for human consumption to avail maximum health benefits. Thus, enhancing the n-3 PUFA content while retaining it in the glyceride form with green technology is the need of the hour. In this study, refined Indian Sardine oil was subjected to selective hydrolysis by Candida antartica lipase to enhance n-3 PUFA content. The degree of hydrolysis and enhancement of n-3 PUFA content was estimated by determining acid value, Iodine value, EPA and DHA content (by Gas Chromatographic methods after derivitization) before and after hydrolysis. Various reaction parameters such as pH, temperature, enzyme load, lipid to aqueous phase volume ratio and incubation time were optimized by conducting trials with one parameter at a time approach. Incubating enzyme solution with refined sardine oil with a volume ratio of 1:1, at pH 7.0, for 60 minutes at 50 °C, with an enzyme load of 60 mg/ml was found to be optimum. After enzymatic treatment, the oil was subjected to refining to remove free fatty acids and moisture content using previously optimized refining technology. Enzymatic treatment at the optimal conditions resulted in 12.11 % enhancement in Degree of hydrolysis. Iodine number had increased by 9.7 % and n-3 PUFA content was enhanced by 112 % (w/w). Selective enhancement of n-3 PUFA glycerides, eliminating saturated and unsaturated fatty acids from the oil using enzyme is an interesting preposition as this technique is environment-friendly, cost effective and provide natural source of n-3 PUFA rich oil.

Keywords: Candida antartica, lipase, n-3 polyunsaturated fatty acids, sardine oil

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2220 A Post-Occupancy Evaluation of Urban Landscape Greenway– A Case Study of the Taiyuan Greenway in Taichung City

Authors: A. Yu-Chen Chien, B. Ying-Ju Su

Abstract:

Greenway is a type of linear park which links the planar parklands and connects the open spaces. In the urban environment, except for providing open spaces with recreational function as well as effectively improve the appearance of the surrounding environment, greenway and parkland also creates benefits to the social and psychological aspects of human. In 2014, the statistics of The Ministry of Home Affairs show that citizens in Taichung enjoy the green area at an average of 4.27 square kilometers per person. How to use the existing green space system effectively and enhance the quality of leisure life thus become the major issues today. The study here points out that greenway and parkland and other open spaces are closely related to the daily life of urban residents. Whether the operation could be executed in accordance with the design is our major concern. To explore the issue, we implemented the Post-Occupancy Evaluation of Taiyuan Greenway in Taichung City. In 1956, Taichung city carried out the urban plan according to Howard’s concept about “Garden City” and built the Taiyuan greenway to restrain the urban expansion. 50-year past, due to the population growth and new demands, the government started to reconstruct the program. It is a three stage modification project of “The Townspace Renaissance project in Taiwan” since 2009, of which the greenway construction is the main point. In this research, we mainly focus on the third stage of this program to investigate the user’s preference and degree of satisfaction based on the Post-Occupancy Evaluation about the finished, unfinished, and undergoing construction sectors as well as facilities. We collected and analyzed the data based on the questionnaires and explored the possible facts that might have affected the degree of satisfaction about the greenway modification project based on the chi-square test. We hope to inspect the purpose of the demonstration projects and provide reference to the Taichung government for the modification planning and the greenway design in the future.

Keywords: greenway, landscape greenway, post-occupancy evaluation, Taichung city

Procedia PDF Downloads 302
2219 A Test to Express Diagnostic Cohesion of Football Team

Authors: Alexandra O. Savinkina

Abstract:

We proposed to assess the cohesion of a football team by its subject-goal and subject-value unity according to the A.V. Petrovsky theory. Goal unity was measured by the degree of compliance of the priority targets for various players in the team. Values were estimated by the coincidence of the ideas about a perfect football player. On the basis of the provisional diagnosis of the six teams, we had made the lists of goals and values. The tests were piloted on 35 football teams. The results allowed not only to compare quantitatively the cohesion of the different teams, but also to identify subgroups within the team.

Keywords: cohesion, football, psychodiagnostic, soccer, sports team, value-orientation unity

Procedia PDF Downloads 246
2218 Design of a 4-DOF Robot Manipulator with Optimized Algorithm for Inverse Kinematics

Authors: S. Gómez, G. Sánchez, J. Zarama, M. Castañeda Ramos, J. Escoto Alcántar, J. Torres, A. Núñez, S. Santana, F. Nájera, J. A. Lopez

Abstract:

This paper shows in detail the mathematical model of direct and inverse kinematics for a robot manipulator (welding type) with four degrees of freedom. Using the D-H parameters, screw theory, numerical, geometric and interpolation methods, the theoretical and practical values of the position of robot were determined using an optimized algorithm for inverse kinematics obtaining the values of the particular joints in order to determine the virtual paths in a relatively short time.

Keywords: kinematics, degree of freedom, optimization, robot manipulator

Procedia PDF Downloads 436
2217 Digitization of European SMEs in Tourism and Hospitality: The Case of Greek Hoteliers

Authors: Joanna K. Konstantinou

Abstract:

The aim of this study is to explore the need of small and medium-sized businesses in tourism and hospitality industry to adopt technology and enhance their degree of digitalization, along with the main benefits enjoyed by technology and the main challenges that hinder its adoption. Within a hermeneutic phenomenological perspective, semi-structured interviews were conducted with three hotel owners and the focus was to identify the main reasons of adoption of technology, enablers and barriers. The findings were grouped with the goal of identifying typology of business practices in using and adopting technology.

Keywords: digitization, SMEs, tourism and hospitality, challenges, benefits

Procedia PDF Downloads 230
2216 The Effect of Three-Dimensional Morphology on Vulnerability Assessment of Atherosclerotic Plaque

Authors: M. Zareh, H. Mohammadi, B. Naser

Abstract:

Atherosclerotic plaque rupture is the main trigger of heart attack and brain stroke which are the leading cause of death in developed countries. Better understanding of rupture-prone plaque can help clinicians detect vulnerable plaques- rupture prone or instable plaques- and apply immediate medical treatment to prevent these life-threatening cardiovascular events. Therefore, there are plenty of studies addressing disclosure of vulnerable plaques properties. Necrotic core and fibrous tissue are two major tissues constituting atherosclerotic plaque; using histopathological and numerical approaches, many studies have demonstrated that plaque rupture is strongly associated with a large necrotic core and a thin fibrous cap, two morphological characteristic which can be acquired by two-dimensional imaging of atherosclerotic plaque present in coronary and carotid arteries. Plaque rupture is widely considered as a mechanical failure inside plaque tissue; this failure occurs when the stress within plaque excesses the strength of tissue material; hence, finite element method, a strong numerical approach, has been extensively applied to estimate stress distribution within plaques with different compositions which is then used for assessment of various vulnerability characteristics including plaque morphology, material properties and blood pressure. This study aims to evaluate significance of three-dimensional morphology on vulnerability degree of atherosclerotic plaque. To reach this end, different two-dimensional geometrical models of atherosclerotic plaques are considered based on available data and named Main 2D Models (M2M). Then, for each of these M2Ms, two three-dimensional idealistic models are created. These two 3D models represent two possible three-dimensional morphologies which might exist for a plaque with similar 2D morphology to one of M2Ms. Finite element method is employed to estimate stress, von-Mises stress, within each 3D models. Results indicate that for each M2Ms stress can significantly varies due to possible 3D morphological changes in that plaque. Also, our results show that an atherosclerotic plaque with thick cap may experience rupture if it has a critical 3D morphology. This study highlights the effect of 3D geometry of plaque on its instability degree and suggests that 3D morphology of plaque might be necessary to more effectively and accurately assess atherosclerotic plaque vulnerability.

Keywords: atherosclerotic plaque, plaque rupture, finite element method, 3D model

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2215 Enabling Socio Cultural Sustainability of the "Thousand and One Churches" Archaeological Site

Authors: E. Erdogan, M. Ulusoy

Abstract:

In terms of tourism, the concept of sustainability can be defined as preserving and developing natural, historical, cultural, social, and aesthetic values and enabling their permanency. Sustainable tourism aims to preserve natural, historical, cultural, and social resources, also by supporting economic progress protecting economic development and environmental values that emerge as a consequence of tourism activities. Cultural tourism feeds on sustainable cultural treasures inherently and is the most effective touristic activity. Traditional configurations and structural characteristics play an important role in generating cultural tourism in a region. Sustainable cultural tourism is related to trips upon people who embark with the aim of visiting culturally rich regions, learning about and observing fast-disappearing lifestyles and collecting cultural values as memories. With its huge tourism potential, Karadağ is the most significant cultural asset of the Karaman province, possessing unique riches in terms of cultural world history. Host to one of the most important Byzantine cities in Anatolia, Karadağ is like an open-air museum with its unparalleled architectural structures. There is a village named Madenşehir in the plain at the outskirts of Karadağ, near to which are located the “Thousand and One Churches” ruins. The 80-household house is located near the ruins in an area that been declared a 1st degree historic preservation district. stones gathered from local churches were used in the construction of these households. A ministry has assigned a new residential site near the boundaries of the 2nd degree preservation district, and the decision has been made to move the occupants to this area. The most important issue here is to enable locals’ sociocultural and socioeconomic sustainability. It is also important to build these structures in a manner compatible with the historical visual look, ecological system and environmental awareness. Therefore this new site will be planned as touristic area in terms of sustainable cultural tourism and in these new plans, shall fulfill functions oriented toward both tourists and locals. It is very important that this change be sustainable and also support cultural tourism.

Keywords: cultural tourism, new village settlement, socio cultural sustainability, “thousand and one churches” site

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2214 The Role of Twitter Bots in Political Discussion on 2019 European Elections

Authors: Thomai Voulgari, Vasilis Vasilopoulos, Antonis Skamnakis

Abstract:

The aim of this study is to investigate the effect of the European election campaigns (May 23-26, 2019) on Twitter achieving with artificial intelligence tools such as troll factories and automated inauthentic accounts. Our research focuses on the last European Parliamentary elections that took place between 23 and 26 May 2019 specifically in Italy, Greece, Germany and France. It is difficult to estimate how many Twitter users are actually bots (Echeverría, 2017). Detection for fake accounts is becoming even more complicated as AI bots are made more advanced. A political bot can be programmed to post comments on a Twitter account for a political candidate, target journalists with manipulated content or engage with politicians and artificially increase their impact and popularity. We analyze variables related to 1) the scope of activity of automated bots accounts and 2) degree of coherence and 3) degree of interaction taking into account different factors, such as the type of content of Twitter messages and their intentions, as well as the spreading to the general public. For this purpose, we collected large volumes of Twitter accounts of party leaders and MEP candidates between 10th of May and 26th of July based on content analysis of tweets based on hashtags while using an innovative network analysis tool known as MediaWatch.io (https://mediawatch.io/). According to our findings, one of the highest percentage (64.6%) of automated “bot” accounts during 2019 European election campaigns was in Greece. In general terms, political bots aim to proliferation of misinformation on social media. Targeting voters is a way that it can be achieved contribute to social media manipulation. We found that political parties and individual politicians create and promote purposeful content on Twitter using algorithmic tools. Based on this analysis, online political advertising play an important role to the process of spreading misinformation during elections campaigns. Overall, inauthentic accounts and social media algorithms are being used to manipulate political behavior and public opinion.

Keywords: artificial intelligence tools, human-bot interactions, political manipulation, social networking, troll factories

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2213 The Persistence of Abnormal Return on Assets: An Exploratory Analysis of the Differences between Industries and Differences between Firms by Country and Sector

Authors: José Luis Gallizo, Pilar Gargallo, Ramon Saladrigues, Manuel Salvador

Abstract:

This study offers an exploratory statistical analysis of the persistence of annual profits across a sample of firms from different European Union (EU) countries. To this end, a hierarchical Bayesian dynamic model has been used which enables the annual behaviour of those profits to be broken down into a permanent structural and a transitory component, while also distinguishing between general effects affecting the industry as a whole to which each firm belongs and specific effects affecting each firm in particular. This breakdown enables the relative importance of those fundamental components to be more accurately evaluated by country and sector. Furthermore, Bayesian approach allows for testing different hypotheses about the homogeneity of the behaviour of the above components with respect to the sector and the country where the firm develops its activity. The data analysed come from a sample of 23,293 firms in EU countries selected from the AMADEUS data-base. The period analysed ran from 1999 to 2007 and 21 sectors were analysed, chosen in such a way that there was a sufficiently large number of firms in each country sector combination for the industry effects to be estimated accurately enough for meaningful comparisons to be made by sector and country. The analysis has been conducted by sector and by country from a Bayesian perspective, thus making the study more flexible and realistic since the estimates obtained do not depend on asymptotic results. In general terms, the study finds that, although the industry effects are significant, more important are the firm specific effects. That importance varies depending on the sector or the country in which the firm carries out its activity. The influence of firm effects accounts for around 81% of total variation and display a significantly lower degree of persistence, with adjustment speeds oscillating around 34%. However, this pattern is not homogeneous but depends on the sector and country analysed. Industry effects depends also on sector and country analysed have a more marginal importance, being significantly more persistent, with adjustment speeds oscillating around 7-8% with this degree of persistence being very similar for most of sectors and countries analysed.

Keywords: dynamic models, Bayesian inference, MCMC, abnormal returns, persistence of profits, return on assets

Procedia PDF Downloads 378
2212 Quality Assessment of Pedestrian Streets in Iran: Case Study of Saf, Tehran

Authors: Fstemeh Rais Esmaili, Ehsan Ranjbar

Abstract:

Pedestrian streets as one type of urban public spaces have an important role in improving the quality of urban life. In Iran, planning and designing of pedestrian streets is in its primary steps. In spite of starting this approach in Iran, and designing several pedestrian streets, there are still not organized studies about quality assessment of pedestrian streets. As a result, the strength and weakness points of the initial experiences have not been utilized. This inattention to quality assessment have caused designing pedestrian streets to be limited to just vehicles traffic control and preliminary actions like paving; so that, special potentials of pedestrian streets for creating social, livable and dynamic public spaces have not been used. This article, as an organized study about quality assessment of pedestrian streets in Iran, tries to reach two main goals: first, introducing a framework for quality assessment of pedestrian streets in Iran, and second, creating a context for improving the quality of pedestrian streets especially for further experiences. The main research methods are description and context analyzing. With respect to comparative analysis of ideas about quality, considering international and local case studies and analyzing existing condition of Saf Pedestrian Street, a particular model for quality assessment has been introduced. In this model, main components and assessment criteria have been presented. On the basis of this model, questionnaire and checklist for assessment have been prepared. The questionnaire and interview have been used to assess qualities which are in direct contact with people and the checklist has been used for analyzing visual qualities by authors through observation. Some results of questionnaire and checklist show that 7 of 11 primary components, diversity, flexibility, cleanness, legibility and imaginably, identity, livability, form and physical setting are rated low and very low in quality degree. Three components, efficiency, comfort and distinctiveness, have medium and low quality degree and one component, access, linkage and permeability has high quality degree. Therefore, based on implemented analyzing process, Saf Pedestrian Street needs to be improved and these quality improvement priorities are determined based on presented criteria. Adaption of final results with existing condition illustrates the shortage of services for satisfying user’s needs, inflexibility and impossibility of using spaces in various times, lack of facilities for different climatic conditions, lack of facilities such as drinking fountain, inappropriate designing of existing urban furniture like garbage cans, and creating pollution and unsuitable view, lack of visual attractions, neglecting disabled persons in designing entrances, shortage of benches and their undesirable designing, lack of vegetation, absence of special characters making it different from other streets, preventing people taking part in the space causing lack of affiliation, lack of appropriate elements for leisure time and lack of exhilaration in the space. On the other hand, these results present high access and permeability, high safety, less sound pollution and more relief, comfortable movement along the way due to suitable pavement and economic efficiency, as the strength points of Saf pedestrian street.

Keywords: pedestrian streets, quality assessment, quality criteria, Saf Pedestrian Street

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2211 The Effectiveness of Prefabricated Vertical Drains for Accelerating Consolidation of Tunis Soft Soil

Authors: Marwa Ben Khalifa, Zeineb Ben Salem, Wissem Frikha

Abstract:

The purpose of the present work is to study the consolidation behavior of highly compressible Tunis soft soil “TSS” by means of prefabricated vertical drains (PVD’s) associated to preloading based on laboratory and field investigations. In the first hand, the field performance of PVD’s on the layer of Tunis soft soil was analysed based on the case study of the construction of embankments of “Radès la Goulette” bridge project. PVD’s Geosynthetics drains types were installed with triangular grid pattern until 10 m depth associated with step-by-step surcharge. The monitoring of the soil settlement during preloading stage for Radès La Goulette Bridge project was provided by an instrumentation composed by various type of tassometer installed in the soil. The distribution of water pressure was monitored through piezocone penetration. In the second hand, a laboratory reduced tests are performed on TSS subjected also to preloading and improved with PVD's Mebradrain 88 (Mb88) type. A specific test apparatus was designed and manufactured to study the consolidation. Two series of consolidation tests were performed on TSS specimens. The first series included consolidation tests for soil improved by one central drain. In thesecond series, a triangular mesh of three geodrains was used. The evolution of degree of consolidation and measured settlements versus time derived from laboratory tests and field data were presented and discussed. The obtained results have shown that PVD’s have considerably accelerated the consolidation of Tunis soft soil by shortening the drainage path. The model with mesh of three drains gives results more comparative to field one. A longer consolidation time is observed for the cell improved by a single central drain. A comparison with theoretical analysis, basically that of Barron (1948) and Carillo (1942), was presented. It’s found that these theories overestimate the degree of consolidation in the presence of PVD.

Keywords: tunis soft soil, prefabricated vertical drains, acceleration of consolidation, dissipation of excess pore water pressures, radès bridge project, barron and carillo’s theories

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2210 Analyzing Students’ Preferences for Academic Advising: Cases of Two Institutions in Greater Tokyo in Japan

Authors: Megumi Yamasaki, Eiko Shimizu

Abstract:

The term academic advisor system first appeared in 2012 in Japan. After ten years, it is not yet functioning. One of Japanese college students’ characteristics is that they choose an institution but may not be interested in a major and want to earn a degree for a career. When the university encourages students to develop competencies as well as students to set personal goals during college life, it is critical to support students develop self-directed attitudes and advocacy skills. This paper will analyze the students’ current stage and how academic advising supports their development.

Keywords: academic advising, student development, self-directed, self-advocacy

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2209 The K-Distance Neighborhood Polynomial of a Graph

Authors: Soner Nandappa D., Ahmed Mohammed Naji

Abstract:

In a graph G = (V, E), the distance from a vertex v to a vertex u is the length of shortest v to u path. The eccentricity e(v) of v is the distance to a farthest vertex from v. The diameter diam(G) is the maximum eccentricity. The k-distance neighborhood of v, for 0 ≤ k ≤ e(v), is Nk(v) = {u ϵ V (G) : d(v, u) = k}. In this paper, we introduce a new distance degree based topological polynomial of a graph G is called a k- distance neighborhood polynomial, denoted Nk(G, x). It is a polynomial with the coefficient of the term k, for 0 ≤ k ≤ e(v), is the sum of the cardinalities of Nk(v) for every v ϵ V (G). Some properties of k- distance neighborhood polynomials are obtained. Exact formulas of the k- distance neighborhood polynomial for some well-known graphs, Cartesian product and join of graphs are presented.

Keywords: vertex degrees, distance in graphs, graph operation, Nk-polynomials

Procedia PDF Downloads 509