Search results for: direct steam generation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6814

Search results for: direct steam generation

874 Development and Structural Characterization of a Snack Food with Added Type 4 Extruded Resistant Starch

Authors: Alberto A. Escobar Puentes, G. Adriana García, Luis F. Cuevas G., Alejandro P. Zepeda, Fernando B. Martínez, Susana A. Rincón

Abstract:

Snack foods are usually classified as ‘junk food’ because have little nutritional value. However, due to the increase on the demand and third generation (3G) snacks market, low price and easy to prepare, can be considered as carriers of compounds with certain nutritional value. Resistant starch (RS) is classified as a prebiotic fiber it helps to control metabolic problems and has anti-cancer colon properties. The active compound can be developed by chemical cross-linking of starch with phosphate salts to obtain a type 4 resistant starch (RS4). The chemical reaction can be achieved by extrusion, a process widely used to produce snack foods, since it's versatile and a low-cost procedure. Starch is the major ingredient for snacks 3G manufacture, and the seeds of sorghum contain high levels of starch (70%), the most drought-tolerant gluten-free cereal. Due to this, the aim of this research was to develop a snack (3G), with RS4 in optimal conditions extrusion (previously determined) from sorghum starch, and carry on a sensory, chemically and structural characterization. A sample (200 g) of sorghum starch was conditioned with 4% sodium trimetaphosphate/ sodium tripolyphosphate (99:1) and set to 28.5% of moisture content. Then, the sample was processed in a single screw extruder equipped with rectangular die. The inlet, transport and output temperatures were 60°C, 134°C and 70°C, respectively. The resulting pellets were expanded in a microwave oven. The expansion index (EI), penetration force (PF) and sensory analysis were evaluated in the expanded pellets. The pellets were milled to obtain flour and RS content, degree of substitution (DS), and percentage of phosphorus (% P) were measured. Spectroscopy [Fourier Transform Infrared (FTIR)], X-ray diffraction, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) analysis were performed in order to determine structural changes after the process. The results in 3G were as follows: RS, 17.14 ± 0.29%; EI, 5.66 ± 0.35 and PF, 5.73 ± 0.15 (N). Groups of phosphate were identified in the starch molecule by FTIR: DS, 0.024 ± 0.003 and %P, 0.35±0.15 [values permitted as food additives (<4 %P)]. In this work an increase of the gelatinization temperature after the crosslinking of starch was detected; the loss of granular and vapor bubbles after expansion were observed by SEM; By using X-ray diffraction, loss of crystallinity was observed after extrusion process. Finally, a snack (3G) was obtained with RS4 developed by extrusion technology. The sorghum starch was efficient for snack 3G production.

Keywords: extrusion, resistant starch, snack (3G), Sorghum

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873 Relationship between Leadership and Emotional Intelligence in Educational Supervision in Saudi Arabia

Authors: Jawaher Bakheet Almudarra

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The Saudi Arabian educational system shared the philosophical principles, in its foundation, which concentrated on the achievement of goals, thereby taking up authoritative styles of leadership. However, organisations are beginning to be more liberal in today’s environment than in the 1940s and 1950s, and appealing to emotional intelligence as a tool and skill are needed for effective leadership. In the Saudi Arabian case, such developments are characterised by changes such as that of the educational supervisor having the role redefined to that of a director. This review tracks several parts: the first section helps western reader to understand the subtleties, complexities, and intricacies of the Saudi Arabia education system and its approach to leadership system of education, history, culture and political contribution. This can lead to the larger extent understand if emotional intelligence is a provocation for better leadership of Saudi Arabian education sector or not. The second part is the growth of educational supervision in Saudi Arabia, focusing on the education system, and evaluates the impact of emotional intelligence as a necessary skill in leadership. The third section looks at emotions and emotional intelligence, gender roles, and contributions by emotional intelligence in the education system. The education system of Saudi Arabia has undergone significant transformation. To fully understand the current climate of Saudi Arabia, it is essential to review this process of transformation in terms of the historical, cultural, political and social positions and transformations. Over the years, the education system in Saudi Arabia has undergone significant metamorphosis. The Saudi government has instituted a wide range of reforms in an attempt to improve education standards and outcomes, facilitate improvements and ensure that high standards of education standards are upheld to keep pace with the global environment and knowledge economy. Leadership itself has become an increasingly prominent aspect of educational reform worldwide. Emotional intelligence is often considered a significant aspect of leadership, but it is in its early stages in Saudi Arabia. Its recognition and adoption may improve leadership practices, particularly among educational supervisors and contribute to national and international understandings of leadership in Saudi Arabia. Studying leadership in the Saudi Arabian context is imperative as the new generation of leaders need to cultivate pertinent skills that will allow them to become fundamentally and positively involved in the regions’ decision making processes in order to impact the progression of the Saudi Arabian education system. Understanding leadership in the education context will allow for suitable inculcation of leadership skills. These skills include goal-setting, sound decision-making as well as problem-solving within the education system of Saudi Arabia.

Keywords: educational supervision, educational administration, emotional intelligence, educational leadership

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872 Anatomical and Histochemical Investigation of the Leaf of Vitex agnus-castus L.

Authors: S. Mamoucha, J. Rahul, N. Christodoulakis

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Introduction: Nature has been the source of medicinal agents since the dawn of the human existence on Earth. Currently, millions of people, in the developing world, rely on medicinal plants for primary health care, income generation and lifespan improvement. In Greece, more than 5500 plant taxa are reported while about 250 of them are considered to be of great pharmaceutical importance. Among the plants used for medical purposes, Vitex agnus-castus L. (Verbenaceae) is known since ancient times. It is a small tree or shrub, widely distributed in the Mediterranean basin up to the Central Asia. It is also known as chaste tree or monks pepper. Theophrastus mentioned the shrub several times, as ‘agnos’ in his ‘Enquiry into Plants’. Dioscorides mentioned the use of V. agnus-castus for the stimulation of lactation in nursing mothers and the treatment of several female disorders. The plant has important medicinal properties and a long tradition in folk medicine as an antimicrobial, diuretic, digestive and insecticidal agent. Materials and methods: Leaves were cleaned, detached, fixed, sectioned and investigated with light and Scanning Electron Microscopy (SEM). Histochemical tests were executed as well. Specific histochemical reagents (osmium tetroxide, H2SO4, vanillin/HCl, antimony trichloride, Wagner’ s reagent, Dittmar’ s reagent, potassium bichromate, nitroso reaction, ferric chloride and di methoxy benzaldehyde) were used for the sub cellular localization of secondary metabolites. Results: Light microscopical investigations of the elongated leaves of V. agnus-castus revealed three layers of palisade parenchyma, just below the single layered adaxial epidermis. The spongy parenchyma is rather loose. Adaxial epidermal cells are larger in magnitude, compared to those of the abaxial epidermis. Four different types of capitate, secreting trichomes, were localized among the abaxial epidermal cells. Stomata were observed at the abaxial epidermis as well. SEM revealed the interesting arrangement of trichomes. Histochemical treatment on fresh and plastic embedded tissue sections revealed the nature and the sites of secondary metabolites accumulation (flavonoids, steroids, terpenes). Acknowledgment: This work was supported by IKY - State Scholarship Foundation, Athens, Greece.

Keywords: Vitex agnus-castus, leaf anatomy, histochemical reagents, secondary metabolites

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871 Variability of the Speaker's Verbal and Non-Verbal Behaviour in the Process of Changing Social Roles in the English Marketing Discourse

Authors: Yuliia Skrynnik

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This research focuses on the interaction of verbal, non-verbal, and super-verbal communicative components used by the speaker changing social roles in the marketing discourse. The changing/performing of social roles is implemented through communicative strategies and tactics, the structural, semantic, and linguo-pragmatic means of which are characterized by specific features and differ for the performance of either a role of a supplier or a customer. Communication within the marketing discourse is characterized by symmetrical roles’ relation between communicative opponents. The strategy of a supplier’s social role realization and the strategy of a customer’s role realization influence the discursive personality's linguistic repertoire in the marketing discourse. This study takes into account that one person can be both a supplier and a customer under different circumstances, thus, exploring the one individual who can be both a supplier and a customer. Cooperative and non-cooperative tactics are the instruments for the implementation of these strategies. In the marketing discourse, verbal and non-verbal behaviour of the speaker performing a customer’s social role is highly informative for speakers who perform the role of a supplier. The research methods include discourse, context-situational, pragmalinguistic, pragmasemantic analyses, the method of non-verbal components analysis. The methodology of the study includes 5 steps: 1) defining the configurations of speakers’ social roles on the selected material; 2) establishing the type of the discourse (marketing discourse); 3) describing the specific features of a discursive personality as a subject of the communication in the process of social roles realization; 4) selecting the strategies and tactics which direct the interaction in different roles configurations; 5) characterizing the structural, semantic and pragmatic features of the strategies and tactics realization, including the analysis of interaction between verbal and non-verbal components of communication. In the marketing discourse, non-verbal behaviour is usually spontaneous but not purposeful. Thus, the adequate decoding of a partner’s non-verbal behavior provides more opportunities both for the supplier and the customer. Super-verbal characteristics in the marketing discourse are crucial in defining the opponent's social status and social role at the initial stage of interaction. The research provides the scenario of stereotypical situations of the play of a supplier and a customer. The performed analysis has perspectives for further research connected with the study of discursive variativity of speakers' verbal and non-verbal behaviour considering the intercultural factor influencing the process of performing the social roles in the marketing discourse; and the formation of the methods for the scenario construction of non-stereotypical situations of social roles realization/change in the marketing discourse.

Keywords: discursive personality, marketing discourse, non-verbal component of communication, social role, strategy, super-verbal component of communication, tactic, verbal component of communication

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870 Flow Links Curiosity and Creativity: The Mediating Role of Flow

Authors: Nicola S. Schutte, John M. Malouff

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Introduction: Curiosity is a positive emotion and motivational state that consists of the desire to know. Curiosity consists of several related dimensions, including a desire for exploration, deprivation sensitivity, and stress tolerance. Creativity involves generating novel and valuable ideas or products. How curiosity may prompt greater creativity remains to be investigated. The phenomena of flow may link curiosity and creativity. Flow is characterized by intense concentration and absorption and gives rise to optimal performance. Objective of Study: The objective of the present study was to investigate whether the phenomenon of flow may link curiosity with creativity. Methods and Design: Fifty-seven individuals from Australia (45 women and 12 men, mean age of 35.33, SD=9.4) participated. Participants were asked to design a program encouraging residents in a local community to conserve water and to record the elements of their program in writing. Participants were then asked to rate their experience as they developed and wrote about their program. Participants rated their experience on the Dimensional Curiosity Measure sub-scales assessing the exploration, deprivation sensitivity, and stress tolerance facets of curiosity, and the Flow Short Scale. Reliability of the measures as assessed by Cronbach's alpha was as follows: Exploration Curiosity =.92, Deprivation Sensitivity Curiosity =.66, Stress Tolerance Curiosity =.93, and Flow=.96. Two raters independently coded each participant’s water conservation program description on creativity. The mixed-model intraclass correlation coefficient for the two sets of ratings was .73. The mean of the two ratings produced the final creativity score for each participant. Results: During the experience of designing the program, all three types of curiosity were significantly associated with the flow. Pearson r correlations were as follows: Exploration Curiosity and flow, r =.68 (higher Exploration Curiosity was associated with more flow); Deprivation Sensitivity Curiosity and flow, r =.39 (higher Deprivation Sensitivity Curiosity was associated with more flow); and Stress Tolerance Curiosity and flow, r = .44 (more stress tolerance in relation to novelty and exploration was associated with more flow). Greater experience of flow was significantly associated with greater creativity in designing the water conservation program, r =.39. The associations between dimensions of curiosity and creativity did not reach significance. Even though the direct relationships between dimensions of curiosity and creativity were not significant, indirect relationships through the mediating effect of the experience of flow between dimensions of curiosity and creativity were significant. Mediation analysis using PROCESS showed that flow linked Exploration Curiosity with creativity, standardized beta=.23, 95%CI [.02,.25] for the indirect effect; Deprivation Sensitivity Curiosity with creativity, standardized beta=.14, 95%CI [.04,.29] for the indirect effect; and Stress Tolerance Curiosity with creativity, standardized beta=.13, 95%CI [.02,.27] for the indirect effect. Conclusions: When engaging in an activity, higher levels of curiosity are associated with greater flow. More flow is associated with higher levels of creativity. Programs intended to increase flow or creativity might build on these findings and also explore causal relationships.

Keywords: creativity, curiosity, flow, motivation

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869 The Situation of Transgender Individuals Was Worsened During Covid-19

Authors: Kajal Attri

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Introduction: Transgender people are considered third gender in India, although they still face identification issues and alienated from society. Furthermore, they face several challenges, including discrimination in employment, resources, education, and property as a result, most transgender people make a living through begging at traffic lights, trains, and buses; attending auspicious occasions such as childbirth and weddings; and engaging in sex work, which includes both home-based and street-based sex work. During COVID-19, maintaining social distance exacerbates transgender people's circumstances and prevents them from accessing health care services, sexual reassignment surgery, identity-based resources, government security, and financial stability. Nonetheless, the pandemic raised unfavorable attitudes about transgender persons, such as unsupportive family members and trouble forming emotional relationships. This study focuses on how we missed transgender people during COVID-19 to provide better facilities to cope with this situation when they are already the most vulnerable segment of the society. Methodology: The research was conducted using secondary data from published publications and grey literature obtained from four databases: Pubmed, Psychinfo, Science direct, and Google scholar. The literature included total 25 articles that met the inclusion criteria for a review. Result and Discussion: Transgender people, who are considered the most vulnerable sector of society, have already faced several obstacles as a result of the outbreak. The analysis underscores the difficulties that transgender persons faced during COVID-19, such as, They had trouble accessing the government's social security programmes during the lockdown, which provide rations and pensions since they lack the necessary identifying cards. The impact of COVID-19 leaves transgender people at heightened risk of poverty and ill health because they exist on the margins of society, those livelihood base on sex work, begging, and participation on auspicious occasions. They had a significant risk of contracting SARS-CoV2 because they lived in congested areas or did not have permanent shelter, and they were predominantly infected with HIV, cancer, and other non-communicable illnesses. The pandemic raised unfavorable attitudes about transgender persons, such as unsupportive family members and trouble forming emotional relationships. Conclusion: The study comes forward with useful suggestions based on content analysis and information to reduce the existing woes of transgenders during any pandemic like COVID-19.

Keywords: COVID-19, transgender, lockdown, transwomen, stigmatization

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868 Identification of Damage Mechanisms in Interlock Reinforced Composites Using a Pattern Recognition Approach of Acoustic Emission Data

Authors: M. Kharrat, G. Moreau, Z. Aboura

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The latest advances in the weaving industry, combined with increasingly sophisticated means of materials processing, have made it possible to produce complex 3D composite structures. Mainly used in aeronautics, composite materials with 3D architecture offer better mechanical properties than 2D reinforced composites. Nevertheless, these materials require a good understanding of their behavior. Because of the complexity of such materials, the damage mechanisms are multiple, and the scenario of their appearance and evolution depends on the nature of the exerted solicitations. The AE technique is a well-established tool for discriminating between the damage mechanisms. Suitable sensors are used during the mechanical test to monitor the structural health of the material. Relevant AE-features are then extracted from the recorded signals, followed by a data analysis using pattern recognition techniques. In order to better understand the damage scenarios of interlock composite materials, a multi-instrumentation was set-up in this work for tracking damage initiation and development, especially in the vicinity of the first significant damage, called macro-damage. The deployed instrumentation includes video-microscopy, Digital Image Correlation, Acoustic Emission (AE) and micro-tomography. In this study, a multi-variable AE data analysis approach was developed for the discrimination between the different signal classes representing the different emission sources during testing. An unsupervised classification technique was adopted to perform AE data clustering without a priori knowledge. The multi-instrumentation and the clustered data served to label the different signal families and to build a learning database. This latter is useful to construct a supervised classifier that can be used for automatic recognition of the AE signals. Several materials with different ingredients were tested under various solicitations in order to feed and enrich the learning database. The methodology presented in this work was useful to refine the damage threshold for the new generation materials. The damage mechanisms around this threshold were highlighted. The obtained signal classes were assigned to the different mechanisms. The isolation of a 'noise' class makes it possible to discriminate between the signals emitted by damages without resorting to spatial filtering or increasing the AE detection threshold. The approach was validated on different material configurations. For the same material and the same type of solicitation, the identified classes are reproducible and little disturbed. The supervised classifier constructed based on the learning database was able to predict the labels of the classified signals.

Keywords: acoustic emission, classifier, damage mechanisms, first damage threshold, interlock composite materials, pattern recognition

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867 Heat Transfer Performance of a Small Cold Plate with Uni-Directional Porous Copper for Cooling Power Electronics

Authors: K. Yuki, R. Tsuji, K. Takai, S. Aramaki, R. Kibushi, N. Unno, K. Suzuki

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A small cold plate with uni-directional porous copper is proposed for cooling power electronics such as an on-vehicle inverter with the heat generation of approximately 500 W/cm2. The uni-directional porous copper with the pore perpendicularly orienting the heat transfer surface is soldered to a grooved heat transfer surface. This structure enables the cooling liquid to evaporate in the pore of the porous copper and then the vapor to discharge through the grooves. In order to minimize the cold plate, a double flow channel concept is introduced for the design of the cold plate. The cold plate consists of a base plate, a spacer, and a vapor discharging plate, totally 12 mm in thickness. The base plate has multiple nozzles of 1.0 mm in diameter for the liquid supply and 4 slits of 2.0 mm in width for vapor discharging, and is attached onto the top surface of the porous copper plate of 20 mm in diameter and 5.0 mm in thickness. The pore size is 0.36 mm and the porosity is 36 %. The cooling liquid flows into the porous copper as an impinging jet flow from the multiple nozzles, and then the vapor, which is generated in the pore, is discharged through the grooves and the vapor slits outside the cold plate. A heated test section consists of the cold plate, which was explained above, and a heat transfer copper block with 6 cartridge heaters. The cross section of the heat transfer block is reduced in order to increase the heat flux. The top surface of the block is the grooved heat transfer surface of 10 mm in diameter at which the porous copper is soldered. The grooves are fabricated like latticework, and the width and depth are 1.0 mm and 0.5 mm, respectively. By embedding three thermocouples in the cylindrical part of the heat transfer block, the temperature of the heat transfer surface ant the heat flux are extrapolated in a steady state. In this experiment, the flow rate is 0.5 L/min and the flow velocity at each nozzle is 0.27 m/s. The liquid inlet temperature is 60 °C. The experimental results prove that, in a single-phase heat transfer regime, the heat transfer performance of the cold plate with the uni-directional porous copper is 2.1 times higher than that without the porous copper, though the pressure loss with the porous copper also becomes higher than that without the porous copper. As to the two-phase heat transfer regime, the critical heat flux increases by approximately 35% by introducing the uni-directional porous copper, compared with the CHF of the multiple impinging jet flow. In addition, we confirmed that these heat transfer data was much higher than that of the ordinary single impinging jet flow. These heat transfer data prove high potential of the cold plate with the uni-directional porous copper from the view point of not only the heat transfer performance but also energy saving.

Keywords: cooling, cold plate, uni-porous media, heat transfer

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866 Subjective Temporal Resources: On the Relationship Between Time Perspective and Chronic Time Pressure to Burnout

Authors: Diamant Irene, Dar Tamar

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Burnout, conceptualized within the framework of stress research, is to a large extent a result of a threat on resources of time or a feeling of time shortage. In reaction to numerous tasks, deadlines, high output, management of different duties encompassing work-home conflicts, many individuals experience ‘time pressure’. Time pressure is characterized as the perception of a lack of available time in relation to the amount of workload. It can be a result of local objective constraints, but it can also be a chronic attribute in coping with life. As such, time pressure is associated in the literature with general stress experience and can therefore be a direct, contributory burnout factor. The present study examines the relation of chronic time pressure – feeling of time shortage and of being rushed, with another central aspect in subjective temporal experience - time perspective. Time perspective is a stable personal disposition, capturing the extent to which people subjectively remember the past, live the present and\or anticipate the future. Based on Hobfoll’s Conservation of Resources Theory, it was hypothesized that individuals with chronic time pressure would experience a permanent threat on their time resources resulting in relatively increased burnout. In addition, it was hypothesized that different time perspective profiles, based on Zimbardo’s typology of five dimensions – Past Positive, Past Negative, Present Hedonistic, Present Fatalistic, and Future, would be related to different magnitudes of chronic time pressure and of burnout. We expected that individuals with ‘Past Negative’ or ‘Present Fatalist’ time perspectives would experience more burnout, with chronic time pressure being a moderator variable. Conversely, individuals with a ‘Present Hedonistic’ - with little concern with the future consequences of actions, would experience less chronic time pressure and less burnout. Another temporal experience angle examined in this study is the difference between the actual distribution of time (as in a typical day) versus desired distribution of time (such as would have been distributed optimally during a day). It was hypothesized that there would be a positive correlation between the gap between these time distributions and chronic time pressure and burnout. Data was collected through an online self-reporting survey distributed on social networks, with 240 participants (aged 21-65) recruited through convenience and snowball sampling methods from various organizational sectors. The results of the present study support the hypotheses and constitute a basis for future debate regarding the elements of burnout in the modern work environment, with an emphasis on subjective temporal experience. Our findings point to the importance of chronic and stable temporal experiences, as time pressure and time perspective, in occupational experience. The findings are also discussed with a view to the development of practical methods of burnout prevention.

Keywords: conservation of resources, burnout, time pressure, time perspective

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865 Self-Assembling Layered Double Hydroxide Nanosheets on β-FeOOH Nanorods for Reducing Fire Hazards of Epoxy Resin

Authors: Wei Wang, Yuan Hu

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Epoxy resins (EP), one of the most important thermosetting polymers, is widely applied in various fields due to its desirable properties, such as excellent electrical insulation, low shrinkage, outstanding mechanical stiffness, satisfactory adhesion and solvent resistance. However, like most of the polymeric materials, EP has the fatal drawbacks including inherent flammability and high yield of toxic smoke, which restricts its application in the fields requiring fire safety. So, it is still a challenge and an interesting subject to develop new flame retardants which can not only remarkably improve the flame retardancy, but also render modified resins low toxic gases generation. In recent work, polymer nanocomposites based on nanohybrids that contain two or more kinds of nanofillers have drawn intensive interest, which can realize performance enhancements. The realization of previous hybrids of carbon nanotubes (CNTs) and molybdenum disulfide provides us a novel route to decorate layered double hydroxide (LDH) nanosheets on the surface of β-FeOOH nanorods; the deposited LDH nanosheets can fill the network and promote the work efficiency of β-FeOOH nanorods. Moreover, the synergistic effects between LDH and β-FeOOH can be anticipated to have potential applications in reducing fire hazards of EP composites for the combination of condense-phase and gas-phase mechanism. As reported, β-FeOOH nanorods can act as a core to prepare hybrid nanostructures combining with other nanoparticles through electrostatic attraction through layer-by-layer assembly technique. In this work, LDH nanosheets wrapped β-FeOOH nanorods (LDH-β-FeOOH) hybrids was synthesized by a facile method, with the purpose of combining the characteristics of one dimension (1D) and two dimension (2D), to improve the fire resistance of epoxy resin. The hybrids showed a well dispersion in EP matrix and had no obvious aggregation. Thermogravimetric analysis and cone calorimeter tests confirmed that LDH-β-FeOOH hybrids into EP matrix with a loading of 3% could obviously improve the fire safety of EP composites. The plausible flame retardancy mechanism was explored by thermogravimetric infrared (TG-IR) and X-ray photoelectron spectroscopy. The reasons were concluded: condense-phase and gas-phase. Nanofillers were transferred to the surface of matrix during combustion, which could not only shield EP matrix from external radiation and heat feedback from the fire zone, but also efficiently retard transport of oxygen and flammable pyrolysis.

Keywords: fire hazards, toxic gases, self-assembly, epoxy

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864 The Effects of Geographical and Functional Diversity of Collaborators on Quality of Knowledge Generated

Authors: Ajay Das, Sandip Basu

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Introduction: There is increasing recognition that diverse streams of knowledge can often be recombined in novel ways to generate new knowledge. However, knowledge recombination theory has not been applied to examine the effects of collaborator diversity on the quality of knowledge such collaborators produce. This is surprising because one would expect that a collaborative team with certain aspects of diversity should be able to recombine process elements related to knowledge development, which are relatively tacit, but also complementary because of the collaborator’s varying backgrounds. Theory and Hypotheses: We propose to examine two aspects of diversity in the environments of collaborative teams to try and capture such potential recombinations of relatively tacit, process knowledge. The first aspect of diversity in team members’ environments is geographical. Collaborators with more geographical distance between them (perhaps working in different countries) often have more autonomy in the processes they adopt for knowledge development. In the absence of overt monitoring, such collaborators are likely to adopt differing approaches to knowledge development. The sharing of such varying approaches among collaborators is likely to result in greater quality of the common collaborative pursuit. The second aspect is diversity in the work backgrounds of team members. Such diversity can also increase the potential for knowledge recombination. For example, if one or more members are from a manufacturing center (versus all of them being from a purely R&D center), such members will provide unique perspectives on the implementation of innovative ideas. Again, knowledge that has been evaluated from these diverse perspectives is likely to be of a higher quality. In addition to the above aspects of environmental diversity among team members, we also plan to examine the extent to which individual collaborators are in different environments from the primary innovation center of their employing firms. Proposed Methods: We will test our model on a sample of firms in the semiconductor industry. Our level of analysis will be individual patents generated by these firms and the teams involved in the generation of these. Information on manufacturing activities of our sample firms will be obtained from SEMI, a proprietary database of the semiconductor industry, as well as company 10-K reports. Conclusion: We believe that our results will represent a preliminary attempt to understand how various forms of diversity in collaborative teams impact the knowledge development process. Our dependent variable of knowledge quality is important to study since higher values of this variable can not only drive firm performance but the broader development of regions and societies through spillover impacts on future innovation. The results of this study will, therefore, inform future research and practice in innovation, geographical location, and vertical integration.

Keywords: innovation, manufacturing strategy, knowledge, diversity

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863 Integrating Machine Learning and Rule-Based Decision Models for Enhanced B2B Sales Forecasting and Customer Prioritization

Authors: Wenqi Liu, Reginald Bailey

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This study proposes a comprehensive and effective approach to business-to-business (B2B) sales forecasting by integrating advanced machine learning models with a rule-based decision-making framework. The methodology addresses the critical challenge of optimizing sales pipeline performance and improving conversion rates through predictive analytics and actionable insights. The first component involves developing a classification model to predict the likelihood of conversion, aiming to outperform traditional methods such as logistic regression in terms of accuracy, precision, recall, and F1 score. Feature importance analysis highlights key predictive factors, such as client revenue size and sales velocity, providing valuable insights into conversion dynamics. The second component focuses on forecasting sales value using a regression model, designed to achieve superior performance compared to linear regression by minimizing mean absolute error (MAE), mean squared error (MSE), and maximizing R-squared metrics. The regression analysis identifies primary drivers of sales value, further informing data-driven strategies. To bridge the gap between predictive modeling and actionable outcomes, a rule-based decision framework is introduced. This model categorizes leads into high, medium, and low priorities based on thresholds for conversion probability and predicted sales value. By combining classification and regression outputs, this framework enables sales teams to allocate resources effectively, focus on high-value opportunities, and streamline lead management processes. The integrated approach significantly enhances lead prioritization, increases conversion rates, and drives revenue generation, offering a robust solution to the declining pipeline conversion rates faced by many B2B organizations. Our findings demonstrate the practical benefits of blending machine learning with decision-making frameworks, providing a scalable, data-driven solution for strategic sales optimization. This study underscores the potential of predictive analytics to transform B2B sales operations, enabling more informed decision-making and improved organizational outcomes in competitive markets.

Keywords: machine learning, XGBoost, regression, decision making framework, system engineering

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862 Robust Electrical Segmentation for Zone Coherency Delimitation Base on Multiplex Graph Community Detection

Authors: Noureddine Henka, Sami Tazi, Mohamad Assaad

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The electrical grid is a highly intricate system designed to transfer electricity from production areas to consumption areas. The Transmission System Operator (TSO) is responsible for ensuring the efficient distribution of electricity and maintaining the grid's safety and quality. However, due to the increasing integration of intermittent renewable energy sources, there is a growing level of uncertainty, which requires a faster responsive approach. A potential solution involves the use of electrical segmentation, which involves creating coherence zones where electrical disturbances mainly remain within the zone. Indeed, by means of coherent electrical zones, it becomes possible to focus solely on the sub-zone, reducing the range of possibilities and aiding in managing uncertainty. It allows faster execution of operational processes and easier learning for supervised machine learning algorithms. Electrical segmentation can be applied to various applications, such as electrical control, minimizing electrical loss, and ensuring voltage stability. Since the electrical grid can be modeled as a graph, where the vertices represent electrical buses and the edges represent electrical lines, identifying coherent electrical zones can be seen as a clustering task on graphs, generally called community detection. Nevertheless, a critical criterion for the zones is their ability to remain resilient to the electrical evolution of the grid over time. This evolution is due to the constant changes in electricity generation and consumption, which are reflected in graph structure variations as well as line flow changes. One approach to creating a resilient segmentation is to design robust zones under various circumstances. This issue can be represented through a multiplex graph, where each layer represents a specific situation that may arise on the grid. Consequently, resilient segmentation can be achieved by conducting community detection on this multiplex graph. The multiplex graph is composed of multiple graphs, and all the layers share the same set of vertices. Our proposal involves a model that utilizes a unified representation to compute a flattening of all layers. This unified situation can be penalized to obtain (K) connected components representing the robust electrical segmentation clusters. We compare our robust segmentation to the segmentation based on a single reference situation. The robust segmentation proves its relevance by producing clusters with high intra-electrical perturbation and low variance of electrical perturbation. We saw through the experiences when robust electrical segmentation has a benefit and in which context.

Keywords: community detection, electrical segmentation, multiplex graph, power grid

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861 Training 'Green Ambassadors' in the Community-Action Learning Course

Authors: Friman Hen, Banner Ifaa, Shalom-Tuchin Bosmat, Einav Yulia

Abstract:

The action learning course is an academic course which involves academic learning and social activities. The courses deal with processes and social challenges, reveal different ideologies, and develop critical thinking and pragmatic ideas. Students receive course credits and a grade for being part of such courses. Participating students enroll in courses that involve action and activities to engage in the experiential learning process, thereby creating a dialogue and cross-fertilization between being taught in the classroom and experiencing the reality in the real world. A learning experience includes meeting with social organizations, institutions, and state authorities and carrying out practical work with diverse populations. Through experience, students strengthen their academic skills, formulate ethical attitudes toward reality, develop professional and civilian perspectives, and realize how they can influence their surrounding in the present and the hereafter. Under the guidance and supervision of Dr. Hen Friman, H.I.T. has built an innovative course that combines action and activities to increase the awareness and accessibility of the community in an experiential way. The end goal is to create Green Ambassadors—children with a high level of environmental awareness. This course is divided into two parts. The first part, focused on frontal teaching, delivers knowledge from extensive environmental fields to students. These areas include introduction to ecology, the process of electricity generation, air pollution, renewable energy, water economy, waste and recycling, and energy efficiency (first stage). In addition to the professional content in the environment field, students learn the method of effective and experiential teaching to younger learners (4 to 8 years old). With the attainment of knowledge, students are divided into operating groups. The second part of the course shows how the theory becomes practical and concrete. At this stage, students are asked to introduce to the first- and second-graders of ‘Revivim’ School in Holon a lesson of 90 minutes focused on presenting the issues and their importance during the course (second stage). This course is the beginning of a paradigm shift regarding energy usage in the modern society in Israel. The objective of the course is to expand worldwide and train the first and second-graders, and even pre-schoolers, in a wide scope to increase population awareness rate, both in Israel and all over the world, for a green future.

Keywords: air pollution, green ambassador, recycling, renewable energy

Procedia PDF Downloads 242
860 User Expectations and Opinions Related to Campus Wayfinding and Signage Design: A Case Study of Kastamonu University

Authors: Güllü Yakar, Adnan Tepecik

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A university campus resembles an independent city that is spread over a wide area. Campuses that incorporate thousands of new domestic and international users at the beginning of every academic period also host scientific, cultural and sportive events, in addition to embodying regular users such as students and staff. Wayfinding and signage systems are necessary for the regulation of vehicular traffic, and they enable users’ to navigate without losing time or feeling anxiety. While designing the system or testing the functionality of it, opinions of existing users or likely behaviors of typical user profiles (personas) provide designers with insight. The purpose of this study is to identify the wayfinding attitudes and expectations of Kastamonu University Kuzeykent Campus users. This study applies a mixed method in which a questionnaire, developed by the researcher, constitute the quantitative phase of the study. The survey was carried out with 850 participants who filled a questionnaire form which was tested in terms of construct validity by using Exploratory Factor Analysis. While interpreting the data obtained, Chi-Square, T- Test and ANOVA analyses were applied as well as descriptive analyses such as frequency (f) and percentage (%) values. The results of this survey, which was conducted during the absence of systematic wayfinding signs in the campus, reveals the participants expectations for insertion of floor plans and wayfinding signs to indoors, maps to outdoors, symbols and color codes to the existing signs and for the adequate arrangement of those for the use of visually impaired people. The fact that there is a direct proportional relation between the length of institution membership and wayfinding competency within campus, leads to the conclusion that especially the new comers are in need of wayfinding signs. In order to determine the effectiveness of campus-wide wayfinding system implemented after the survey and in order to identify the further expectations of users in this respect, a semi-structured interview form developed by the researcher and assessments of 20 participants are compiled. Subjected to content analysis, this data constitute the qualitative dimension of the study. Research results indicate that despite the presence of the signs, the participants experienced either inability or stress while finding their way, showed tendency to receive help from others and needed outdoor maps and signs, in addition to bigger-sized texts.

Keywords: environmental graphic design, environmental perception, wayfinding and signage design, wayfinding system

Procedia PDF Downloads 237
859 Improvement in Oral Health-Related Quality of Life of Adult Patients After Rehabilitation With Partial Dentures: A Systematic Review and Meta-Analysis

Authors: Adama NS Bah

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Background: Loss of teeth has a negative influence on essential oral functions such as phonetics, mastication, and aesthetics. Dentists treat people with prosthodontic rehabilitation to recover essential oral functions. The oral health quality of life inventory reflects the success of prosthodontic rehabilitation. In many countries, the current conventional care delivered to replace missing teeth for adult patients involves the provision of removable partial dentures. Aim: The aim of this systematic review and meta-analysis is to gather the best available evidence to determine patients’ oral health-related quality of life improvement after treatment with partial dentures. Methods: We searched electronic databases from January 2010 to September 2019, including PubMed, ProQuest, Science Direct, Scopus and Google Scholar. In this paper, studies were included only if the average age was 30 years and above and also published in English. Two reviewers independently screened and selected all the references based on inclusion criteria using the PRISMA guideline, and assessed the quality of the included references using the Joanna Briggs Institute quality assessment tools. Data extracted were analyzed in RevMan 5.0 software, the heterogeneity between the studies was assessed using Forest plot, I2 statistics and chi-square test with a statistical P value less than 0.05 to indicate statistical significance. Random effect models were used in case of moderate or high heterogeneity. Four studies were included in the systematic review and three studies were pooled for meta-analysis. Results: Four studies included in the systematic review and three studies included in the meta-analysis with a total of 285 patients comparing the improvement in oral health-related quality of life before and after rehabilitation with partial denture, the pooled results showed a better improvement of oral health-related quality of life after treatment with partial dentures (mean difference 5.25; 95% CI [3.81, 6.68], p < 0.00001) favoring the wearing of partial dentures. In order to ascertain the reliability of the included studies for meta-analysis risk of bias was assessed and found to be low in all included studies for meta-analysis using the Cochrane collaboration tool for risk of bias assessment. Conclusion: There is high evidence that rehabilitation with partial dentures can improve the patient’s oral health-related quality of life measured with Oral Health Impact Profile 14. This review has clinical evidence value for dentists treating the expanding vulnerable adult population.

Keywords: meta-analysis, oral health impact profile, partial dentures, systematic review

Procedia PDF Downloads 107
858 Greenhouse Gasses’ Effect on Atmospheric Temperature Increase and the Observable Effects on Ecosystems

Authors: Alexander J. Severinsky

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Radiative forces of greenhouse gases (GHG) increase the temperature of the Earth's surface, more on land, and less in oceans, due to their thermal capacities. Given this inertia, the temperature increase is delayed over time. Air temperature, however, is not delayed as air thermal capacity is much lower. In this study, through analysis and synthesis of multidisciplinary science and data, an estimate of atmospheric temperature increase is made. Then, this estimate is used to shed light on current observations of ice and snow loss, desertification and forest fires, and increased extreme air disturbances. The reason for this inquiry is due to the author’s skepticism that current changes cannot be explained by a "~1 oC" global average surface temperature rise within the last 50-60 years. The only other plausible cause to explore for understanding is that of atmospheric temperature rise. The study utilizes an analysis of air temperature rise from three different scientific disciplines: thermodynamics, climate science experiments, and climactic historical studies. The results coming from these diverse disciplines are nearly the same, within ± 1.6%. The direct radiative force of GHGs with a high level of scientific understanding is near 4.7 W/m2 on average over the Earth’s entire surface in 2018, as compared to one in pre-Industrial time in the mid-1700s. The additional radiative force of fast feedbacks coming from various forms of water gives approximately an additional ~15 W/m2. In 2018, these radiative forces heated the atmosphere by approximately 5.1 oC, which will create a thermal equilibrium average ground surface temperature increase of 4.6 oC to 4.8 oC by the end of this century. After 2018, the temperature will continue to rise without any additional increases in the concentration of the GHGs, primarily of carbon dioxide and methane. These findings of the radiative force of GHGs in 2018 were applied to estimates of effects on major Earth ecosystems. This additional force of nearly 20 W/m2 causes an increase in ice melting by an additional rate of over 90 cm/year, green leaves temperature increase by nearly 5 oC, and a work energy increase of air by approximately 40 Joules/mole. This explains the observed high rates of ice melting at all altitudes and latitudes, the spread of deserts and increases in forest fires, as well as increased energy of tornadoes, typhoons, hurricanes, and extreme weather, much more plausibly than the 1.5 oC increase in average global surface temperature in the same time interval. Planned mitigation and adaptation measures might prove to be much more effective when directed toward the reduction of existing GHGs in the atmosphere.

Keywords: greenhouse radiative force, greenhouse air temperature, greenhouse thermodynamics, greenhouse historical, greenhouse radiative force on ice, greenhouse radiative force on plants, greenhouse radiative force in air

Procedia PDF Downloads 104
857 Discourse Analysis: Where Cognition Meets Communication

Authors: Iryna Biskub

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The interdisciplinary approach to modern linguistic studies is exemplified by the merge of various research methods, which sometimes causes complications related to the verification of the research results. This methodological confusion can be resolved by means of creating new techniques of linguistic analysis combining several scientific paradigms. Modern linguistics has developed really productive and efficient methods for the investigation of cognitive and communicative phenomena of which language is the central issue. In the field of discourse studies, one of the best examples of research methods is the method of Critical Discourse Analysis (CDA). CDA can be viewed both as a method of investigation, as well as a critical multidisciplinary perspective. In CDA the position of the scholar is crucial from the point of view exemplifying his or her social and political convictions. The generally accepted approach to obtaining scientifically reliable results is to use a special well-defined scientific method for researching special types of language phenomena: cognitive methods applied to the exploration of cognitive aspects of language, whereas communicative methods are thought to be relevant only for the investigation of communicative nature of language. In the recent decades discourse as a sociocultural phenomenon has been the focus of careful linguistic research. The very concept of discourse represents an integral unity of cognitive and communicative aspects of human verbal activity. Since a human being is never able to discriminate between cognitive and communicative planes of discourse communication, it doesn’t make much sense to apply cognitive and communicative methods of research taken in isolation. It is possible to modify the classical CDA procedure by means of mapping human cognitive procedures onto the strategic communicative planning of discourse communication. The analysis of the electronic petition 'Block Donald J Trump from UK entry. The signatories believe Donald J Trump should be banned from UK entry' (584, 459 signatures) and the parliamentary debates on it has demonstrated the ability to map cognitive and communicative levels in the following way: the strategy of discourse modeling (communicative level) overlaps with the extraction of semantic macrostructures (cognitive level); the strategy of discourse management overlaps with the analysis of local meanings in discourse communication; the strategy of cognitive monitoring of the discourse overlaps with the formation of attitudes and ideologies at the cognitive level. Thus, the experimental data have shown that it is possible to develop a new complex methodology of discourse analysis, where cognition would meet communication, both metaphorically and literally. The same approach may appear to be productive for the creation of computational models of human-computer interaction, where the automatic generation of a particular type of a discourse could be based on the rules of strategic planning involving cognitive models of CDA.

Keywords: cognition, communication, discourse, strategy

Procedia PDF Downloads 254
856 Spatial and Temporal Analysis of Forest Cover Change with Special Reference to Anthropogenic Activities in Kullu Valley, North-Western Indian Himalayan Region

Authors: Krisala Joshi, Sayanta Ghosh, Renu Lata, Jagdish C. Kuniyal

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Throughout the world, monitoring and estimating the changing pattern of forests across diverse landscapes through remote sensing is instrumental in understanding the interactions of human activities and the ecological environment with the changing climate. Forest change detection using satellite imageries has emerged as an important means to gather information on a regional scale. Kullu valley in Himachal Pradesh, India is situated in a transitional zone between the lesser and the greater Himalayas. Thus, it presents a typical rugged mountainous terrain with moderate to high altitude which varies from 1200 meters to over 6000 meters. Due to changes in agricultural cropping patterns, urbanization, industrialization, hydropower generation, climate change, tourism, and anthropogenic forest fire, it has undergone a tremendous transformation in forest cover in the past three decades. The loss and degradation of forest cover results in soil erosion, loss of biodiversity including damage to wildlife habitats, and degradation of watershed areas, and deterioration of the overall quality of nature and life. The supervised classification of LANDSAT satellite data was performed to assess the changes in forest cover in Kullu valley over the years 2000 to 2020. Normalized Burn Ratio (NBR) was calculated to discriminate between burned and unburned areas of the forest. Our study reveals that in Kullu valley, the increasing number of forest fire incidents specifically, those due to anthropogenic activities has been on a rise, each subsequent year. The main objective of the present study is, therefore, to estimate the change in the forest cover of Kullu valley and to address the various social aspects responsible for the anthropogenic forest fires. Also, to assess its impact on the significant changes in the regional climatic factors, specifically, temperature, humidity, and precipitation over three decades, with the help of satellite imageries and ground data. The main outcome of the paper, we believe, will be helpful for the administration for making a quantitative assessment of the forest cover area changes due to anthropogenic activities and devising long-term measures for creating awareness among the local people of the area.

Keywords: Anthropogenic Activities, Forest Change Detection, Normalized Burn Ratio (NBR), Supervised Classification

Procedia PDF Downloads 173
855 Analysis of Sea Waves Characteristics and Assessment of Potential Wave Power in Egyptian Mediterranean Waters

Authors: Ahmed A. El-Gindy, Elham S. El-Nashar, Abdallah Nafaa, Sameh El-Kafrawy

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The generation of energy from marine energy became one of the most preferable resources since it is a clean source and friendly to environment. Egypt has long shores along Mediterranean with important cities that need energy resources with significant wave energy. No detailed studies have been done on wave energy distribution in the Egyptian waters. The objective of this paper is to assess the energy wave power available in the Egyptian waters for the choice of the most suitable devices to be used in this area. This paper deals the characteristics and power of the offshore waves in the Egyptian waters. Since the field observations of waves are not frequent and need much technical work, the European Centre for Medium-Range Weather Forecasts (ECMWF) interim reanalysis data in Mediterranean, with a grid size 0.75 degree, which is a relatively course grid, are considered in the present study for preliminary assessment of sea waves characteristics and power. The used data covers the period from 2012 to 2014. The data used are significant wave height (swh), mean wave period (mwp) and wave direction taken at six hourly intervals, at seven chosen stations, and at grid points covering the Egyptian waters. The wave power (wp) formula was used to calculate energy flux. Descriptive statistical analysis including monthly means and standard deviations of the swh, mwp, and wp. The percentiles of wave heights and their corresponding power are done, as a tool of choice of the best technology suitable for the site. The surfer is used to show spatial distributions of wp. The analysis of data at chosen 7 stations determined the potential of wp off important Egyptian cities. Offshore of Al Saloum and Marsa Matruh, the highest wp occurred in January and February (16.93-18.05) ± (18.08-22.12) kw/m while the lowest occurred in June and October (1.49-1.69) ± (1.45-1.74) kw/m. In front of Alexandria and Rashid, the highest wp occurred in January and February (16.93-18.05) ± (18.08-22.12) kw/m while the lowest occurred in June and September (1.29-2.01) ± (1.31-1.83) kw/m. In front of Damietta and Port Said, the highest wp occurred in February (14.29-17.61) ± (21.61-27.10) kw/m and the lowest occurred in June (0.94-0.96) ± (0.71-0.72) kw/m. In winter, the probabilities of waves higher than 0.8 m in percentage were, at Al Saloum and Marsa Matruh (76.56-80.33) ± (11.62-12.05), at Alexandria and Rashid (73.67-74.79) ± (16.21-18.59) and at Damietta and Port Said (66.28-68.69) ± (17.88-17.90). In spring, the percentiles were, at Al Saloum and Marsa Matruh, (48.17-50.92) ± (5.79-6.56), at Alexandria and Rashid, (39.38-43.59) ± (9.06-9.34) and at Damietta and Port Said, (31.59-33.61) ± (10.72-11.25). In summer, the probabilities were, at Al Saloum and Marsa Matruh (57.70-66.67) ± (4.87-6.83), at Alexandria and Rashid (59.96-65.13) ± (9.14-9.35) and at Damietta and Port Said (46.38-49.28) ± (10.89-11.47). In autumn, the probabilities were, at Al Saloum and Marsa Matruh (58.75-59.56) ± (2.55-5.84), at Alexandria and Rashid (47.78-52.13) ± (3.11-7.08) and at Damietta and Port Said (41.16-42.52) ± (7.52-8.34).

Keywords: distribution of sea waves energy, Egyptian Mediterranean waters, waves characteristics, waves power

Procedia PDF Downloads 192
854 Startup Ecosystem in India: Development and Impact

Authors: Soham Chakraborty

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This article examines the development of start-up culture in India, its development as well as related impact on the Indian society. Another vibrant synonym of start-up in the present century can be starting afresh. Startups have become the new flavor of this decade. A startup ecosystem is formed by mainly the new generation in the making. A startup ecosystem involves a variety of elements without which a startup can never prosper, they are—ideas, inventions, innovations as well as authentic research in the field into which one is interested, mentors, advisors, funding bodies, service provider organizations, angel, venture and so on. The culture of startup is quiet nascent but rampant in India. This is largely due to the widespread of media as a medium through which the newfangled entrepreneurs can spread their word of mouth far and wide. Different kinds of media such as Television, Radio, Internet, Print media and so on, act as the weapon to any startup company in India. The article explores how there is a sudden shift in the growing Indian economy due to the rise of startup ecosystem. There are various reasons, which are the result of the growing success of startup in India, firstly, entrepreneurs are building up startup ideas on the basis of various international startup but giving them a pinch of Indian flavor; secondly, business models are framed based on the current problems that people face in the modern century; thirdly, balance between social and technological entrepreneurs and lastly, quality of mentorship. The Government of India boasts startup as a flagship initiative. Bunch full of benefits and assistance was declared in an event named as 'Start Up India, Stand Up India' on 16th January 2016 by the current Prime Minister of India Mr. Narendra Modi. One of the biggest boon that increasing startups are creating in the society is the proliferation of self-employment. Noted Startups which are thriving in India are like OYO, Where’s The Food (WTF), TVF Pitchers, Flipkart and so on are examples of India is getting covered up by various innovative startups. The deep impact can be felt by each Indian after a few years as various governmental and non-governmental policies and agendas are helping in the sprawling up of startups and have mushroom growth in India. The impact of startup uprising in India is also possible due to increasing globalization which is leading to the eradication of national borders, thereby creating the environment to enlarge one’s business model. To conclude, this article points out on the correlation between rising startup in Indian market and its increasing developmental benefits for the people at large. Internationally, various business portals are tagging India to be the world’s fastest growing startup ecosystem.

Keywords: business, ecosystem, entrepreneurs, media, globalization, startup

Procedia PDF Downloads 268
853 A Microwave and Millimeter-Wave Transmit/Receive Switch Subsystem for Communication Systems

Authors: Donghyun Lee, Cam Nguyen

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Multi-band systems offer a great deal of benefit in modern communication and radar systems. In particular, multi-band antenna-array radar systems with their extended frequency diversity provide numerous advantages in detection, identification, locating and tracking a wide range of targets, including enhanced detection coverage, accurate target location, reduced survey time and cost, increased resolution, improved reliability and target information. An accurate calibration is a critical issue in antenna array systems. The amplitude and phase errors in multi-band and multi-polarization antenna array transceivers result in inaccurate target detection, deteriorated resolution and reduced reliability. Furthermore, the digital beam former without the RF domain phase-shifting is less immune to unfiltered interference signals, which can lead to receiver saturation in array systems. Therefore, implementing integrated front-end architecture, which can support calibration function with low insertion and filtering function from the farthest end of an array transceiver is of great interest. We report a dual K/Ka-band T/R/Calibration switch module with quasi-elliptic dual-bandpass filtering function implementing a Q-enhanced metamaterial transmission line. A unique dual-band frequency response is incorporated in the reception and calibration path of the proposed switch module utilizing the composite right/left-handed meta material transmission line coupled with a Colpitts-style negative generation circuit. The fabricated fully integrated T/R/Calibration switch module in 0.18-μm BiCMOS technology exhibits insertion loss of 4.9-12.3 dB and isolation of more than 45 dB in the reception, transmission and calibration mode of operation. In the reception and calibration mode, the dual-band frequency response centered at 24.5 and 35 GHz exhibits out-of-band rejection of more than 30 dB compared to the pass bands below 10.5 GHz and above 59.5 GHz. The rejection between the pass bands reaches more than 50 dB. In all modes of operation, the IP1-dB is between 4 and 11 dBm. Acknowledgement: This paper was made possible by NPRP grant # 6-241-2-102 from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors.

Keywords: microwaves, millimeter waves, T/R switch, wireless communications, wireless communications

Procedia PDF Downloads 160
852 Exploring the Contribution of Dynamic Capabilities to a Firm's Value Creation: The Role of Competitive Strategy

Authors: Mona Rashidirad, Hamid Salimian

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Dynamic capabilities, as the most considerable capabilities of firms in the current fast-moving economy may not be sufficient for performance improvement, but their contribution to performance is undeniable. While much of the extant literature investigates the impact of dynamic capabilities on organisational performance, little attention has been devoted to understand whether and how dynamic capabilities create value. Dynamic capabilities as the mirror of competitive strategies should enable firms to search and seize new ideas, integrate and coordinate the firm’s resources and capabilities in order to create value. A careful investigation to the existing knowledge base remains us puzzled regarding the relationship among competitive strategies, dynamic capabilities and value creation. This study thus attempts to fill in this gap by empirically investigating the impact of dynamic capabilities on value creation and the mediating impact of competitive strategy on this relationship. We aim to contribute to dynamic capability view (DCV), in both theoretical and empirical senses, by exploring the impact of dynamic capabilities on firms’ value creation and whether competitive strategy can play any role in strengthening/weakening this relationship. Using a sample of 491 firms in the UK telecommunications market, the results demonstrate that dynamic sensing, learning, integrating and coordinating capabilities play a significant role in firm’s value creation, and competitive strategy mediates the impact of dynamic capabilities on value creation. Adopting DCV, this study investigates whether the value generating from dynamic capabilities depends on firms’ competitive strategy. This study argues a firm’s competitive strategy can mediate its ability to derive value from its dynamic capabilities and it explains the extent a firm’s competitive strategy may influence its value generation. The results of the dynamic capabilities-value relationships support our expectations and justify the non-financial value added of the four dynamic capability processes in a highly turbulent market, such as UK telecommunications. Our analytical findings of the relationship among dynamic capabilities, competitive strategy and value creation provide further evidence of the undeniable role of competitive strategy in deriving value from dynamic capabilities. The results reinforce the argument for the need to consider the mediating impact of organisational contextual factors, such as firm’s competitive strategy to examine how they interact with dynamic capabilities to deliver value. The findings of this study provide significant contributions to theory. Unlike some previous studies which conceptualise dynamic capabilities as a unidimensional construct, this study demonstrates the benefits of understanding the details of the link among the four types of dynamic capabilities, competitive strategy and value creation. In terms of contributions to managerial practices, this research draws attention to the importance of competitive strategy in conjunction with development and deployment of dynamic capabilities to create value. Managers are now equipped with solid empirical evidence which explains why DCV has become essential to firms in today’s business world.

Keywords: dynamic capabilities, resource based theory, value creation, competitive strategy

Procedia PDF Downloads 241
851 Synthesis and Characterizations of Lead-free BaO-Doped TeZnCaB Glass Systems for Radiation Shielding Applications

Authors: Rezaul K. Sk., Mohammad Ashiq, Avinash K. Srivastava

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The use of radiation shielding technology ranging from EMI to high energy gamma rays in various areas such as devices, medical science, defense, nuclear power plants, medical diagnostics etc. is increasing all over the world. However, exposure to different radiations such as X-ray, gamma ray, neutrons and EMI above the permissible limits is harmful to living beings, the environment and sensitive laboratory equipment. In order to solve this problem, there is a need to develop effective radiation shielding materials. Conventionally, lead and lead-based materials are used in making shielding materials, as lead is cheap, dense and provides very effective shielding to radiation. However, the problem associated with the use of lead is its toxic nature and carcinogenic. So, to overcome these drawbacks, there is a great need for lead-free radiation shielding materials and that should also be economically sustainable. Therefore, it is necessary to look for the synthesis of radiation-shielding glass by using other heavy metal oxides (HMO) instead of lead. The lead-free BaO-doped TeZnCaB glass systems have been synthesized by the traditional melt-quenching method. X-ray diffraction analysis confirmed the glassy nature of the synthesized samples. The densities of the developed glass samples were increased by doping the BaO concentration, ranging from 4.292 to 4.725 g/cm3. The vibrational and bending modes of the BaO-doped glass samples were analyzed by Raman spectroscopy, and FTIR (Fourier-transform infrared spectroscopy) was performed to study the functional group present in the samples. UV-visible characterization revealed the significance of optical parameters such as Urbach’s energy, refractive index and optical energy band gap. The indirect and direct energy band gaps were decreased with the BaO concentration whereas the refractive index was increased. X-ray attenuation measurements were performed to determine the radiation shielding parameters such as linear attenuation coefficient (LAC), mass attenuation coefficient (MAC), half value layer (HVL), tenth value layer (TVL), mean free path (MFP), attenuation factor (Att%) and lead equivalent thickness of the lead-free BaO-doped TeZnCaB glass system. It was observed that the radiation shielding characteristics were enhanced with the addition of BaO content in the TeZnCaB glass samples. The glass samples with higher contents of BaO have the best attenuation performance. So, it could be concluded that the addition of BaO into TeZnCaB glass samples is a significant technique to improve the radiation shielding performance of the glass samples. The best lead equivalent thickness was 2.626 mm, and these glasses could be good materials for medical diagnostics applications.

Keywords: heavy metal oxides, lead-free, melt-quenching method, x-ray attenuation

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850 Gas-Phase Nondestructive and Environmentally Friendly Covalent Functionalization of Graphene Oxide Paper with Amines

Authors: Natalia Alzate-Carvajal, Diego A. Acevedo-Guzman, Victor Meza-Laguna, Mario H. Farias, Luis A. Perez-Rey, Edgar Abarca-Morales, Victor A. Garcia-Ramirez, Vladimir A. Basiuk, Elena V. Basiuk

Abstract:

Direct covalent functionalization of prefabricated free-standing graphene oxide paper (GOP) is considered as the only approach suitable for systematic tuning of thermal, mechanical and electronic characteristics of this important class of carbon nanomaterials. At the same time, the traditional liquid-phase functionalization protocols can compromise physical integrity of the paper-like material up to its total disintegration. To avoid such undesirable effects, we explored the possibility of employing an alternative, solvent-free strategy for facile and nondestructive functionalization of GOP with two representative aliphatic amines, 1-octadecylamine (ODA) and 1,12-diaminododecane (DAD), as well as with two aromatic amines, 1-aminopyrene (AP) and 1,5-diaminonaphthalene (DAN). The functionalization was performed under moderate heating at 150-180 °C in vacuum. Under such conditions, it proceeds through both amidation and epoxy ring opening reactions. Comparative characterization of pristine and amine-functionalized GOP mats was carried out by using Fourier-transform infrared, Raman, and X-ray photoelectron spectroscopy (XPS), thermogravimetric (TGA) and differential thermal analysis, scanning electron and atomic force microscopy (SEM and AFM, respectively). Besides that, we compared the stability in water, wettability, electrical conductivity and elastic (Young's) modulus of GOP mats before and after amine functionalization. The highest content of organic species was obtained in the case of GOP-ODA, followed by GOP-DAD, GOP-AP and GOP-DAN samples. The covalent functionalization increased mechanical and thermal stability of GOP, as well as its electrical conductivity. The magnitude of each effect depends on the particular chemical structure of amine employed, which allows for tuning a given GOP property. Morphological characterization by using SEM showed that, compared to pristine graphene oxide paper, amine-modified GOP mats become relatively ordered layered assemblies, in which individual GO sheets are organized in a near-parallel pattern. Financial support from the National Autonomous University of Mexico (grants DGAPA-IN101118 and IN200516) and from the National Council of Science and Technology of Mexico (CONACYT, grant 250655) is greatly appreciated. The authors also thank David A. Domínguez (CNyN of UNAM) for XPS measurements and Dr. Edgar Alvarez-Zauco (Faculty of Science of UNAM) for the opportunity to use TGA equipment.

Keywords: amines, covalent functionalization, gas-phase, graphene oxide paper

Procedia PDF Downloads 182
849 The Environmental Impact Assessment of Land Use Planning (Case Study: Tannery Industry in Al-Garma District)

Authors: Husam Abdulmuttaleb Hashim

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The environmental pollution problems represent a great challenge to the world, threatening to destroy all the evolution that mankind has reached, the organizations and associations that cares about environment are trying to warn the world from the forthcoming danger resulted from excessive use of nature resources and consuming it without looking to the damage happened as a result of unfair use of it. Most of the urban centers suffers from the environmental pollution problems and health, economic, and social dangers resulted from this pollution, and while the land use planning is responsible for distributing different uses in urban centers and controlling the interactions between these uses to reach a homogeneous and perfect state for the different activities in cities, the occurrence of environmental problems in the shade of existing land use planning operation refers to the disorder or insufficiency in this operation which leads to presence of such problems, and this disorder lays in lack of sufficient importance to the environmental considerations during the land use planning operations and setting up the master plan, so the research start to study this problem and finding solutions for it, the research assumes that using accurate and scientific methods in early stages of land use planning operation will prevent occurring of environmental pollution problems in the future, the research aims to study and show the importance of the environmental impact assessment method (EIA) as an important planning tool to investigate and predict the pollution ranges of the land use that has a polluting pattern in land use planning operation. This research encompasses the concept of environmental assessment and its kinds and clarifies environmental impact assessment and its contents, the research also dealt with urban planning concept and land use planning, it also dealt with the current situation of the case study (Al-Garma district) and the land use planning in it and explain the most polluting use on the environment which is the industrial land use represented in the tannery industries and then there was a stating of current situation of this land use and explaining its contents and environmental impacts resulted from it, and then we analyzed the tests applied by the researcher for water and soil, and perform environmental evaluation through applying environmental impact assessment matrix using the direct method to reveal the pollution ranges on the ambient environment of industrial land use, and we also applied the environmental and site limits and standards by using (GIS) and (AUTOCAD) to select the site of the best alternative of the industrial region in Al-Garma district after the research approved the unsuitability of its current site location for the environmental and site limitations, the research conducted some conclusions and recommendations regard clarifying the concluded facts and to set the proper solutions.

Keywords: EIA, pollution, tannery industry, land use planning

Procedia PDF Downloads 449
848 Prenatal Paraben Exposure Impacts Infant Overweight Development and in vitro Adipogenesis

Authors: Beate Englich, Linda Schlittenbauer, Christiane Pfeifer, Isabel Kratochvil, Michael Borte, Gabriele I. Stangl, Martin von Bergen, Thorsten Reemtsma, Irina Lehmann, Kristin M. Junge

Abstract:

The worldwide production of endocrine disrupting compounds (EDC) has risen dramatically over the last decades, as so has the prevalence for obesity. Many EDCs are believed to contribute to this obesity epidemic, by enhancing adipogenesis or disrupting relevant metabolism. This effect is most tremendous in the early prenatal period when priming effects find a highly vulnerable time window. Therefore, we investigate the impact of parabens on childhood overweight development and adipogenesis in general. Parabens are ester of 4-hydroxy-benzoic acid and part of many cosmetic products or food packing. Therefore, ubiquitous exposure can be found in the westernized world, with exposure already starting during the sensitive prenatal period. We assessed maternal cosmetic product consumption, prenatal paraben exposure and infant BMI z-scores in the prospective German LINA cohort. In detail, maternal urinary concentrations (34 weeks of gestation) of methyl paraben (MeP), ethyl paraben (EtP), n-propyl paraben (PrP) and n-butyl paraben (BuP) were quantified using UPLC-MS/MS. Body weight and height of their children was assessed during annual clinical visits. Further, we investigated the direct influence of those parabens on adipogenesis in-vitro using a human mesenchymal stem cell (MSC) differentiation assay to mimic a prenatal exposure scenario. MSC were exposed to 0.1 – 50 µM paraben during the entire differentiation period. Differentiation outcome was monitored by impedance spectrometry, real-time PCR and triglyceride staining. We found that maternal cosmetic product consumption was highly correlated with urinary paraben concentrations at pregnancy. Further, prenatal paraben exposure was linked to higher BMI Z-scores in children. Our in-vitro analysis revealed that especially the long chained paraben BuP stimulates adipogenesis by increasing the expression of adipocyte specific genes (PPARγ, ADIPOQ, LPL, etc.) and triglyceride storage. Moreover, we found that adiponectin secretion is increased whereas leptin secretion is reduced under BuP exposure in-vitro. Further mechanistic analysis for receptor binding and activation of PPARγ and other key players in adipogenesis are currently in process. We conclude that maternal cosmetic product consumption is linked to prenatal paraben exposure of children and contributes to the development of infant overweight development by triggering key pathways of adipogenesis.

Keywords: adipogenesis, endocrine disruptors, paraben, prenatal exposure

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847 Mathematical Model to Simulate Liquid Metal and Slag Accumulation, Drainage and Heat Transfer in Blast Furnace Hearth

Authors: Hemant Upadhyay, Tarun Kumar Kundu

Abstract:

It is utmost important for a blast furnace operator to understand the mechanisms governing the liquid flow, accumulation, drainage and heat transfer between various phases in blast furnace hearth for a stable and efficient blast furnace operation. Abnormal drainage behavior may lead to high liquid build up in the hearth. Operational problems such as pressurization, low wind intake, and lower material descent rates, normally be encountered if the liquid levels in the hearth exceed a critical limit when Hearth coke and Deadman start to float. Similarly, hot metal temperature is an important parameter to be controlled in the BF operation; it should be kept at an optimal level to obtain desired product quality and a stable BF performance. It is not possible to carry out any direct measurement of above due to the hostile conditions in the hearth with chemically aggressive hot liquids. The objective here is to develop a mathematical model to simulate the variation in hot metal / slag accumulation and temperature during the tapping of the blast furnace based on the computed drainage rate, production rate, mass balance, heat transfer between metal and slag, metal and solids, slag and solids as well as among the various zones of metal and slag itself. For modeling purpose, the BF hearth is considered as a pressurized vessel, filled with solid coke particles. Liquids trickle down in hearth from top and accumulate in voids between the coke particles which are assumed thermally saturated. A set of generic mass balance equations gives the amount of metal and slag intake in hearth. A small drainage (tap hole) is situated at the bottom of the hearth and flow rate of liquids from tap hole is computed taking in account the amount of both the phases accumulated their level in hearth, pressure from gases in the furnace and erosion behaviors of tap hole itself. Heat transfer equations provide the exchange of heat between various layers of liquid metal and slag, and heat loss to cooling system through refractories. Based on all that information a dynamic simulation is carried out which provides real time information of liquids accumulation in hearth before and during tapping, drainage rate and its variation, predicts critical event timings during tapping and expected tapping temperature of metal and slag on preset time intervals. The model is in use at JSPL, India BF-II and its output is regularly cross-checked with actual tapping data, which are in good agreement.

Keywords: blast furnace, hearth, deadman, hotmetal

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846 Finite Element Analysis of the Drive Shaft and Jacking Frame Interaction in Micro-Tunneling Method: Case Study of Tehran Sewerage

Authors: B. Mohammadi, A. Riazati, P. Soltan Sanjari, S. Azimbeik

Abstract:

The ever-increasing development of civic demands on one hand; and the urban constrains for newly establish of infrastructures, on the other hand, perforce the engineering committees to apply non-conflicting methods in order to optimize the results. One of these optimized procedures to establish the main sewerage networks is the pipe jacking and micro-tunneling method. The raw information and researches are based on the experiments of the slurry micro-tunneling project of the Tehran main sewerage network that it has executed by the KAYSON co. The 4985 meters route of the mentioned project that is located nearby the Azadi square and the most vital arteries of Tehran is faced to 45% physical progress nowadays. The boring machine is made by the Herrenknecht and the diameter of the using concrete-polymer pipes are 1600 and 1800 millimeters. Placing and excavating several shafts on the ground and direct Tunnel boring between the axes of issued shafts is one of the requirements of the micro-tunneling. Considering the stream of the ground located shafts should care the hydraulic circumstances, civic conditions, site geography, traffic cautions and etc. The profile length has to convert to many shortened segment lines so the generated angle between the segments will be based in the manhole centers. Each segment line between two continues drive and receive the shaft, displays the jack location, driving angle and the path straight, thus, the diversity of issued angle causes the variety of jack positioning in the shaft. The jacking frame fixing conditions and it's associated dynamic load direction produces various patterns of Stress and Strain distribution and creating fatigues in the shaft wall and the soil surrounded the shaft. This pattern diversification makes the shaft wall transformed, unbalanced subsidence and alteration in the pipe jacking Stress Contour. This research is based on experiments of the Tehran's west sewerage plan and the numerical analysis the interaction of the soil around the shaft, shaft walls and the Jacking frame direction and finally, the suitable or unsuitable location of the pipe jacking shaft will be determined.

Keywords: underground structure, micro-tunneling, fatigue analysis, dynamic-soil–structure interaction, underground water, finite element analysis

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845 The Moderating Role of Test Anxiety in the Relationships Between Self-Efficacy, Engagement, and Academic Achievement in College Math Courses

Authors: Yuqing Zou, Chunrui Zou, Yichong Cao

Abstract:

Previous research has revealed relationships between self-efficacy (SE), engagement, and academic achievement among students in Western countries, but these relationships remain unknown in college math courses among college students in China. In addition, previous research has shown that test anxiety has a direct effect on engagement and academic achievement. However, how test anxiety affects the relationships between SE, engagement, and academic achievement is still unknown. In this study, the authors aimed to explore the mediating roles of behavioral engagement (BE), emotional engagement (EE), and cognitive engagement (CE) in the association between SE and academic achievement and the moderating role of test anxiety in college math courses. Our hypotheses are that the association between SE and academic achievement was mediated by engagement and that test anxiety played a moderating role in the association. To explore the research questions, the authors collected data through self-reported surveys among 147 students at a northwestern university in China. Self-reported surveys were used to collect data. The motivated strategies for learning questionnaire (MSLQ) (Pintrich, 1991), the metacognitive strategies questionnaire (Wolters, 2004), and the engagement versus disaffection with learning scale (Skinner et al., 2008) were used to assess SE, CE, and BE and EE, respectively. R software was used to analyze the data. The main analyses used were reliability and validity analysis of scales, descriptive statistics analysis of measured variables, correlation analysis, regression analysis, and structural equation modeling (SEM) analysis and moderated mediation analysis to look at the structural relationships between variables at the same time. The SEM analysis indicated that student SE was positively related to BE, EE, and CE and academic achievement. BE, EE, and CE were all positively associated with academic achievement. That is, as the authors expected, higher levels of SE led to higher levels of BE, EE, and CE, and greater academic achievement. Higher levels of BE, EE, and CE led to greater academic achievement. In addition, the moderated mediation analysis found that the path of SE to academic achievement in the model was as significant as expected, as was the moderating effect of test anxiety in the SE-Achievement association. Specifically, test anxiety was found to moderate the association between SE and BE, the association between SE and CE, and the association between EE and Achievement. The authors investigated possible mediating effects of BE, EE, and CE in the associations between SE and academic achievement, and all indirect effects were found to be significant. As for the magnitude of mediations, behavioral engagement was the most important mediator in the SE-Achievement association. This study has implications for college teachers, educators, and students in China regarding ways to promote academic achievement in college math courses, including increasing self-efficacy and engagement and lessening test anxiety toward math.

Keywords: academic engagement, self-efficacy, test anxiety, academic achievement, college math courses, behavioral engagement, cognitive engagement, emotional engagement

Procedia PDF Downloads 93