Search results for: mixed effect logistic regression model
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 32130

Search results for: mixed effect logistic regression model

9900 Content-Based Mammograms Retrieval Based on Breast Density Criteria Using Bidimensional Empirical Mode Decomposition

Authors: Sourour Khouaja, Hejer Jlassi, Nadia Feddaoui, Kamel Hamrouni

Abstract:

Most medical images, and especially mammographies, are now stored in large databases. Retrieving a desired image is considered of great importance in order to find previous similar cases diagnosis. Our method is implemented to assist radiologists in retrieving mammographic images containing breast with similar density aspect as seen on the mammogram. This is becoming a challenge seeing the importance of density criteria in cancer provision and its effect on segmentation issues. We used the BEMD (Bidimensional Empirical Mode Decomposition) to characterize the content of images and Euclidean distance measure similarity between images. Through the experiments on the MIAS mammography image database, we confirm that the results are promising. The performance was evaluated using precision and recall curves comparing query and retrieved images. Computing recall-precision proved the effectiveness of applying the CBIR in the large mammographic image databases. We found a precision of 91.2% for mammography with a recall of 86.8%.

Keywords: BEMD, breast density, contend-based, image retrieval, mammography

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9899 Effect in Animal Nutrition of Genetical Modified Plant(GM)

Authors: Abdullah Özbilgin, Oguzhan Kahraman, Mustafa Selçuk Alataş

Abstract:

Plant breeders have made and will continue to make important contributions toward meeting the need for more and better feed and food. The use of new techniques to modify the genetic makeup of plants to improve their properties has led to a new generation of crops, grains and their by-products for feed. Plant breeders have made and will continue to make important contributions toward meeting the need for more and better feed and food. The use of new techniques to modify the genetic makeup of plants to improve their properties has led to a new generation of crops, grains and their by-products for feed. The land area devoted to the cultivation of genetically modified (GM) plants has increased in recent years: in 2012 such plants were grown on over 170 million hectares globally, in 28 different countries, and are at resent used by 17.3 million farmers worldwide. The majority of GM plants are used as feed material for food-producing farm animals. Despite the facts that GM plants have been used as feed for years and a number of feeding studies have proved their safety for animals, they still give rise to emotional public discussion.

Keywords: crops, genetical modified plant(GM), plant, safety

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9898 An Exposition of Principles of Islamic Fiscal Policy

Authors: Muhammad A. Ishaq, S. U. R. Aliyu

Abstract:

This paper on an exposition of Islamic fiscal policy attempts to discuss the basic principles of Islamic fiscal policy in an Islamic economy. The paper presents a number of definitions of the subject matter, its nature and its tools of application. Government spending, taxation and public borrowings were identified as the tools of the policy. The paper identifies zakat both as a veritable source of revenue and a major instrument of economic stabilization. Furthermore, the paper presents an algebraic 2-sector and 3-sector models from the basic Keynesian model. The paper posits that in view of uniqueness of its instruments, absence of interest rate in the economy and the policy’s derive towards socioeconomic justice and redistribution, Islamic fiscal policy is capable of stabilizing Islamic economy and ushering it into the path of long term economic growth and prosperity.

Keywords: automatic built-in-stabilizers, government spending, Islamic fiscal policy, taxation, zakat

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9897 Experiences of Students in a Cultural Competence Learning Project in Hong Kong- Themes from Qualitative Analysis

Authors: Diana Kwok

Abstract:

Introduction: There is a rising concern on the educational needs of school guidance teachers, counselors, and sex educators to work effectively with students from multicultural groups, such as racial minorities, gender minorities, sexual minorities, and disability groups etc., and to respect cultural diversities. A specialized training model, the multicultural framework based on contact theory is recognized as necessary training model for professional training programs. Methodology: While the major focus of this project is on improving teaching and learning in teacher training courses within the department of Special Education and Counselling, it specifically aims to enhance the cultural competence of 102 participants enrolled in counseling and sexuality education courses by integrating the following teaching and learning strategies: 1) Panel presentation; 2) Case studies; 3) Experiential learning. Data sources from the participants consisted of the following: (a) questionnaires (MCKAS and ATLG) administered in classes; (b) weekly reflective journals, and c) focus group interviews with panel members. The focus group interviews with panel members were documented. Qualitatively, the weekly reflections were content analyzed. The presentation in this specific conference put focus on themes we found from qualitative content analysis of weekly reflective journals from 102 participants. Findings: Content analysis had found the following preliminary emergent themes: Theme I) Cultural knowledge and challenges to personal limitation. Students had gained a new perspective that specific cultural knowledge involved unique values and worldview. Awareness of limitation of counsellors is very important after actively acquiring the cultural knowledge. Theme 2 - Observation, engagement and active learning. Through the sharing and case studies, as well as visits to the communities, students recognized that observation and listening to the needs of cultural group members were the essential steps before taking any intervention steps. Theme 3 - Curiosity and desire for further inter-group dialogue. All students expressed their desire, curiosity, and motivation to have further inter-group dialogue in their future work settings. Theme 4: Experience with teaching and learning strategies. Students shared their perspectives on how teaching and learning strategies had facilitated their acquisition of cultural competence. Results of this analysis suggests that diverse teaching and learning strategies based on contact perspective had stimulated their curiosity to re-examine their values and motivated them to acquire cultural knowledge relevant to the cultural groups. Acknowledgment: The teaching and learning project was funded by the Teaching and Development Grant, Hong Kong Institute of Education (Project Number T0142).

Keywords: cultural competence, Chinese teacher students, teaching and learning, contacts

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9896 Survey of Corrosion and Scaling of Urban Drinking Water Supply Reservoirs (Case Study: Ilam City)

Authors: Ehsan Derikvand, Hamid Kaykha, Rooholah Mansoori Yekta, Taleb Javanmard, Mohsen Mehdi Zadeh

Abstract:

Corrosion and scaling are one of the most complicated and costly problems of drinking water supply. Corrosion has adverse effect on general health and public acceptance of water source and drinking water supply costs. The present study aimed to determine the potentials of corrosion and scaling of potable water supply reservoirs of Ilam city in June 2013 and August 2014 by Langelier Index (LI) and Reynar. The results of experiments and calculations show that the mean index of LSI in the first and second sampling stages is 0.34, 0.2, respectively and the mean index RSI in the first and second stages of sampling is 7.15 and 7.22, respectively. Based on LSI index of reservoirs water in the first phase, none of stations are corrosive and only one station in the second sampling phase has corrosive tendency. According to RSI index, there is no corrosive tendency in two phases. Based on the results, the water of drinking water reservoirs in Ilam city has no corrosion tendency and the analyses and results of Langelier Index (LI) and Ryznar are in relatively good condition.

Keywords: corrosion, scaling, water reservoirs, langelier and ryznar indices, Ilam city

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9895 Surface Acoustic Wave (SAW)-Induced Mixing Enhances Biomolecules Kinetics in a Novel Phase-Interrogation Surface Plasmon Resonance (SPR) Microfluidic Biosensor

Authors: M. Agostini, A. Sonato, G. Greco, M. Travagliati, G. Ruffato, E. Gazzola, D. Liuni, F. Romanato, M. Cecchini

Abstract:

Since their first demonstration in the early 1980s, surface plasmon resonance (SPR) sensors have been widely recognized as useful tools for detecting chemical and biological species, and the interest of the scientific community toward this technology has known a rapid growth in the past two decades owing to their high sensitivity, label-free operation and possibility of real-time detection. Recent works have suggested that a turning point in SPR sensor research would be the combination of SPR strategies with other technologies in order to reduce human handling of samples, improve integration and plasmonic sensitivity. In this light, microfluidics has been attracting growing interest. By properly designing microfluidic biochips it is possible to miniaturize the analyte-sensitive areas with an overall reduction of the chip dimension, reduce the liquid reagents and sample volume, improve automation, and increase the number of experiments in a single biochip by multiplexing approaches. However, as the fluidic channel dimensions approach the micron scale, laminar flows become dominant owing to the low Reynolds numbers that typically characterize microfluidics. In these environments mixing times are usually dominated by diffusion, which can be prohibitively long and lead to long-lasting biochemistry experiments. An elegant method to overcome these issues is to actively perturb the liquid laminar flow by exploiting surface acoustic waves (SAWs). With this work, we demonstrate a new approach for SPR biosensing based on the combination of microfluidics, SAW-induced mixing and the real-time phase-interrogation grating-coupling SPR technology. On a single lithium niobate (LN) substrate the nanostructured SPR sensing areas, interdigital transducer (IDT) for SAW generation and polydimethylsiloxane (PDMS) microfluidic chambers were fabricated. SAWs, impinging on the microfluidic chamber, generate acoustic streaming inside the fluid, leading to chaotic advection and thus improved fluid mixing, whilst analytes binding detection is made via SPR method based on SPP excitation via gold metallic grating upon azimuthal orientation and phase interrogation. Our device has been fully characterized in order to separate for the very first time the unwanted SAW heating effect with respect to the fluid stirring inside the microchamber that affect the molecules binding dynamics. Avidin/biotin assay and thiol-polyethylene glycol (bPEG-SH) were exploited as model biological interaction and non-fouling layer respectively. Biosensing kinetics time reduction with SAW-enhanced mixing resulted in a ≈ 82% improvement for bPEG-SH adsorption onto gold and ≈ 24% for avidin/biotin binding—≈ 50% and 18% respectively compared to the heating only condition. These results demonstrate that our biochip can significantly reduce the duration of bioreactions that usually require long times (e.g., PEG-based sensing layer, low concentration analyte detection). The sensing architecture here proposed represents a new promising technology satisfying the major biosensing requirements: scalability and high throughput capabilities. The detection system size and biochip dimension could be further reduced and integrated; in addition, the possibility of reducing biological experiment duration via SAW-driven active mixing and developing multiplexing platforms for parallel real-time sensing could be easily combined. In general, the technology reported in this study can be straightforwardly adapted to a great number of biological system and sensing geometry.

Keywords: biosensor, microfluidics, surface acoustic wave, surface plasmon resonance

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9894 The Study of Indigenous Communities in Sefidkuh Makran, the Showcase of Prehistoric Societies in the 21st Century, Based on Ethnoarchaeological Studies

Authors: Hossein Vahedi, Zahra Soleymani Fard

Abstract:

SefidKuh area in Baluchistan, Iran, is one of the impossible areas which the focused archeological investigations have not been on it. In the Sefidkuh area, there are colonies as if they were stopped in the Neolithic and Chalcolithic ages. These colonies exhibit culturally specific behaviors, which their study can reveal much of the cultural nature of the Neolithic, Chalcolithic inhabitants of the region. In the villages of this area, still, circular architecture is used in different types. The political management of the villages in the region is also the responsibility of Khan, whose characteristics can be compared to the prehistoric era. These people's livelihoods include hunting, animal husbandry, horticulture, and limited crop storage. Residents of Sefidkuh use the exchange of goods to obtain needed supplies that they themselves cannot produce. In this area, there are central location villages that are quite similar to the cluster model, and the Great Khan leads the surrounding villages.

Keywords: archaeology, social structure, neolithic, chalcolithic, Sefidkuh, Baluchistan

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9893 Numerical Study of Heat Transfer in Square Duct with Turbulators

Authors: M. H. Alhajeri, Hamad M. Alhajeri, A. H. Alenezi

Abstract:

Computational fluid dynamics (CFD) investigation of heat transfer in U-duct with turbulators is presented in this paper. The duct passages used to cool internally the blades in gas turbine. The study is focused in the flow behavior and the Nusselt number (Nu) distributions. The model of the u-duct contains two square legs that are connected by 180* turn. Four turbulators are located in each surface of the leg and distributed in a staggered arrangement. The turbulator height and width are equal to 0.1 of the duct width, and the turbulator height is 0.1 of the distance between the turbulators. The Reynolds number (Re) used in this study is 95000 and the inlet velocity is 10 m/s. It was noticed that, after the flow resettles from the interruptions generated by the first turbulator or the turn, the flow construct two eddies, one large and the other is small after and before the turbulator, respectively. The maximum values of the Nu are found at a distance of approximately one turbulator width w before of the flow reattachment point.

Keywords: computational fluid dynamics, CFD, rib, heat transfer, blade

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9892 Investigation on The Feasibility of a Solar Desiccant Cooling System in Libya

Authors: A. S. Zgalei, B. T. Al-Mabrouk

Abstract:

With a particularly significant growth rate observed in the Libyan commercial and residential buildings coupled with a growth in energy demand, solar desiccant evaporative cooling offers energy savings and promises a good sharing for sustainable buildings where the availability of solar radiation matches with the cooling load demand. The paper presents a short introduction for the desiccant systems. A mathematical model of a selected system has been developed and a simulation has been performed in order to investigate the system performance at different working conditions and an optimum design of the system structure is established. The results showed a technical feasibility of the system working under the Libyan climatic conditions with a reasonable COP at temperatures that can be obtained through the solar reactivation system. Discussion of the results and the recommendations for future work are proposed.

Keywords: computer program, solar desiccant wheel cooling, system modelling, simulation, technical feasibility

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9891 Numerical Investigation of Electrohydrodynamics: Enhanced Heat Transfer in a Solid Sample

Authors: Suwimon Saneewong Na Ayuttaya

Abstract:

This paper presents a numerical investigation of electrically driven flow for enhancing convective heat transfer in a channel flow. This study focuses on the electrode arrangements, number of electrode and electrical voltage on Electrohydrodynamics (EHD) and effect of airflow driven on solid sample surface. The inlet airflow and inlet temperature are 0.35 m/s and 60 oC, respectively. High electrical voltage is tested in the range of 0-30 kV and number of electrode is tested in the range of 1-5. The numerical results show that electric field intensity is depended on electrical voltage and number of electrode. Increasing number of electrodes is increased shear flow, so swirling flow is increased. The swirling flows from aligned and staggered arrangements are affecting within the solid sample. When electrical voltage is increased, temperature distribution and convective heat transfer on the solid sample are significantly increased due to the electric force much stronger.

Keywords: electrohydrodynamics (EHD), swirling flow, convective heat transfer, solid sample

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9890 An Appraisal of Maintenance Management Practices in Federal University Dutse and Jigawa State Polytechnic Dutse, Nigeria

Authors: Aminu Mubarak Sadis

Abstract:

This study appraised the maintenance management practice in Federal University Dutse and Jigawa State Polytechnic Dutse, in Nigeria. The Physical Planning, Works and Maintenance Departments of the two Higher Institutions (Federal University Dutse and Jigawa State Polytechnic) are responsible for production and maintenance management of their physical assets. Over–enrollment problem has been a common feature in the higher institutions in Nigeria, Data were collected by the administered questionnaires and subsequent oral interview to authenticate the completed questionnaires. Random sampling techniques was used in selecting 150 respondents across the various institutions (Federal University Dutse and Jigawa State Polytechnic Dutse). Data collected was analyzed using Statistical Package for Social Science (SPSS) and t-test statistical techniques The conclusion was that maintenance management activities are yet to be given their appropriate attention on functions of the university and polytechnic which are crucial to improving teaching, learning and research. The unit responsible for maintenance and managing facilities should focus on their stated functions and effect changes were possible.

Keywords: appraisal, maintenance management, university, Polytechnic, practices

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9889 Seismic Performance of Micropiles in Sand with Predrilled Oversized Holes

Authors: Cui Fu, Yi-Zhou Zhuang, Sheng-Zhi Wang

Abstract:

Full scale tests of six micropiles with different predrilled-hole parameters under low frequency cyclic lateral loading in-sand were carried out using the MTS hydraulic loading system to analyze the seismic performance of micropiles. Hysteresis curves, skeleton curves, energy dissipation capacity and ductility of micropiles were investigated. The experimental results show the hysteresis curves appear like plump bows in the elastic–plastic stage and failure stage which exhibit good hysteretic characteristics without pinching phenomena and good energy dissipating capacities. The ductility coefficient varies from 2.51 to 3.54 and the depth and loose backfill of oversized holes can improve ductility, but the diameter of predrilled-hole has a limited effect on enhancing its ductility. These findings and conclusions could make contribution to the practical application of the semi-integral abutment bridges and provide a reference for the predrilled oversized hole technology in integral abutment bridges.

Keywords: ductility, energy dissipation capacity, micropile with predrilled oversized hole, seismic performance, semi-integral abutment bridge

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9888 Nickel Catalyst Promoted with Lanthanum- Alumina for Dry Reforming of Methane

Authors: Radia Imane Fertout

Abstract:

In recent years, the reaction of dry reforming of methane (DRM) has attracted much attention due to its environmental and industrial importance. Various catalysts, including Ni-based catalysts, have been investigated for the DRM. Doping Ni/Al₂O₃ by lanthanum and alkaline earth element may strongly influence solid-state reaction and increases the stability of catalysts due to the lower density and high basicity of these oxides. The effect of SrO on the activity and stability of Ni/Al₂O₃-La₂O₃ in dry reforming of methane was investigated. These catalysts have been prepared with the impregnation method, calcined in air at 450 and 650°C, then characterized by BET surface area, X-ray diffraction (XRD), and scanning electron microscopy (SEM) techniques and tested in DRM. The results showed that the addition of strontium to Ni/Al2O₃-La₂O₃ decreased the specific surface area. XRD results revealed the presence of different phases of Al₂O₃, La(OH)₃, La₂O₂CO₃, and SrCO₃. The catalytic evaluation results showed that adding SrO increased the catalytic activity and stability, that explained by the strong basicity of strontium. SEM analysis after the reaction indicates the formation of carbon over the spent catalyst and that the addition of strontium stabilized the surface of the catalyst.

Keywords: dry reforming of methane, Ni/Al₂O₃-La₂O₃ catalyst, strontium, nickel

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9887 The Effect of the Internal Organization Communications' Effectiveness through Employee's Performance of Faculty of Management Science, Suan Sunandha Rajabhat University

Authors: Malaiphan Pansap, Surasit Vithayarat

Abstract:

The purpose of this study was to study the relationship between internal organization communications’ effectiveness and employee’s performance of Faculty of Management Science, Suan Sunandha Rajabhat University. Study on solutions of communication were carried out within the organization. Questionnaire was used to collect information from 136 people of staff and instructor and data were analyzed by using frequency, percentage, mean and standard deviation and then data processing statistic programs. The result found that organization communication that affects their employee’s performance is sender which lack the skills for speaking and writing to convince audiences ready before taking message and the message which organizations are not always informed. The employees believe the behavior of good organization communication has a positive impact on the development of organization because the employees feel involved and be a part of the organization, by the cooperation in working to achieve the goal, the employees can work in the same direction and meet goal quickly.

Keywords: employee’s performance, faculty of management science, internal organization communications’ effectiveness, management accounting, Suan Sunandha Rajabhat University

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9886 Effect of Problem Based Learning (PBL) Activities to Thai Undergraduate Student Teachers Attitude and Their Achievement

Authors: Thanawit Tongmai, Chatchawan Saewor

Abstract:

Learning management is very important for students’ development. To promote students’ potential, the teacher should design appropriate learning activity that brings their students potential out. Problem based learning has been using worldwide and it has presented numerous of success. This research aims to study third year students’ attitude and their achievement in scientific research course. To find the results, mix method was used to design research conduction. The researcher used PBL and reflection activity in the class. The students had to choose a topic, reviewed information, designed experimental, wrote academic report and presented their research by themselves. The researcher was only a facilitator. Reflection activity was used to progressing and consulting their research. The data was collected along with research conduction by questionnaire and test, including attitude, opinion and their achievement. The result of this study showed that 74.71% from all of students (n = 87) benefited from PBL and reflection activity, while 25.19% were just satisfied. 100% of students had a positive reflection toward PBL activity and they believed that PBL was the best pedagogy method for scientific research course. The achievements of these students were higher than the previous study (P < 0.05). The student’s learning achievement, A, B+ and B, was 48.28, 28.74 and 22.98% respectively. Therefore, it can conclude that PBL activity is appropriate for scientific research course and it can also promote student’s achievement.

Keywords: reflection, attitude, learning, achievement, PBL

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9885 Quantification of Uncertainties Related to the Implementation of Reverse Logistics Process

Authors: Dnaya Soukaina

Abstract:

It’s over six decades that Reverse logistics had appeared as a research area, and it is emerging again and again in the scientific fields. As reverse logistics presents real potential for value recovery and environmental impacts decrease, it’s still necessary to extend this concept more in the industrial and commercial field especially in developing countries. The process of reverse logistics is a progression of steps beginning with the customer and finishing with the organization or even the customer, however the issue is that this cycle must be adjustable to the organization concerned, in addition of legislative, operational, financial and social obstacles. Literature had demonstrated that there are many other uncertainties while the implementation of this process that vary in function of the sector concerned and the kind of activity. Besides, even if literature is developing this topic over the last years, reseraches about uncertainties quantification in reverse logistics process still being few. the paper has the objective to fill this gap, and carry out a study to identify sustainable strategies that can be adapted to different industrial or commercial sectors to facilitate the implementation of reverse logistics.

Keywords: reverse logistics, implementation, unceratinties quantification, mathematical model

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9884 Enabling Rather Than Managing: Organizational and Cultural Innovation Mechanisms in a Heterarchical Organization

Authors: Sarah M. Schoellhammer, Stephen Gibb

Abstract:

Bureaucracy, in particular, its core element, a formal and stable hierarchy of authority, is proving less and less appropriate under the conditions of today’s knowledge economy. Centralization and formalization were consistently found to hinder innovation, undermining cross-functional collaboration, personal responsibility, and flexibility. With its focus on systematical planning, controlling and monitoring the development of new or improved solutions for customers, even innovation management as a discipline is to a significant extent based on a mechanistic understanding of organizations. The most important drivers of innovation, human creativity, and initiative, however, can be more hindered than supported by central elements of classic innovation management, such as predefined innovation strategies, rigid stage gate processes, and decisions made in management gate meetings. Heterarchy, as an alternative network form of organization, is essentially characterized by its dynamic influence structures, whereby the biggest influence is allocated by the collective to the persons perceived the most competent in a certain issue. Theoretical arguments that the non-hierarchical concept better supports innovation than bureaucracy have been supported by empirical research. These prior studies either focus on the structure and general functioning of non-hierarchical organizations or on their innovativeness, that means innovation as an outcome. Complementing classic innovation management approaches, this work aims to shed light on how innovations are initiated and realized in heterarchies in order to identify alternative solutions practiced under conditions of the post-bureaucratic organization. Through an initial individual case study, which is part of a multiple-case project, the innovation practices of an innovative and highly heterarchical medium-sized company in the German fire engineering industry are investigated. In a pragmatic mixed methods approach media resonance, company documents, and workspace architecture are analyzed, in addition to qualitative interviews with the CEO and employees of the case company, as well as a quantitative survey aiming to characterize the company along five scaled dimensions of a heterarchy spectrum. The analysis reveals some similarities and striking differences to approaches suggested by classic innovation management. The studied heterarchy has no predefined innovation strategy guiding new product and service development. Instead, strategic direction is provided by the CEO, described as visionary and creative. Procedures for innovation are hardly formalized, with new product ideas being evaluated on the basis of gut feeling and flexible, rather general criteria. Employees still being hesitant to take responsibility and make decisions, hierarchical influence is still prominent. Described as open-minded and collaborative, culture and leadership were found largely congruent with definitions of innovation culture. Overall, innovation efforts at the case company tend to be coordinated more through cultural than through formal organizational mechanisms. To better enable innovation in mainstream organizations, responsible practitioners are recommended not to limit changes to reducing the central elements of the bureaucratic organization, formalization, and centralization. The freedoms this entails need to be sustained through cultural coordination mechanisms, with personal initiative and responsibility by employees as well as common innovation-supportive norms and values. These allow to integrate diverse competencies, opinions, and activities and, thus, to guide innovation efforts.

Keywords: bureaucracy, heterarchy, innovation management, values

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9883 Effect of Corrugating Bottom Surface on Natural Convection in a Square Porous Enclosure

Authors: Khedidja Bouhadef, Imene Said Kouadri, Omar Rahli

Abstract:

In this paper numerical investigation is performed to analyze natural convection heat transfer characteristics within a wavy-wall enclosure filled with fluid-saturated porous medium. The bottom wall which has the wavy geometry is maintained at a constant high temperature, while the top wall is straight and is maintained at a constant lower temperature. The left and right walls of the enclosure are both straight and insulated. The governing differential equations are solved by Finite-volume approach and grid generation is used to transform the physical complex domain to a computational regular space. The aim is to examine flow field, temperature distribution and heat transfer evolutions inside the cavity when Darcy number, Rayleigh number and undulations number values are varied. The results mainly indicate that the heat transfer is rather affected by the permeability and Rayleigh number values since increasing these values enhance the Nusselt number; although the exchanges are not highly affected by the undulations number.

Keywords: grid generation, natural convection, porous medium, wavy wall enclosure

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9882 Impact Tensile Mechanical Properties of 316L Stainless Steel at Different Strain Rates

Authors: Jiawei Chen, Jia Qu, Dianwei Ju

Abstract:

316L stainless steel has good mechanical and technological properties, has been widely used in shipbuilding and aerospace manufacturing. In order to understand the effect of strain rate on the yield limit of 316L stainless steel and the constitutive relationship of the materials at different strain rates, this paper used the INSTRON-4505 electronic universal testing machine to study the mechanical properties of the tensile specimen under quasi-static conditions. Meanwhile, the Zwick-Roell RKP450 intelligent oscillometric impact tester was used to test the tensile specimens at different strain rates. Through the above two kinds of experimental researches, the relationship between the true stress-strain and the engineering stress-strain at different strain rates is obtained. The result shows that the tensile yield point of 316L stainless steel increases with the increase of strain rate, and the real stress-strain curve of the 316L stainless steel has a better normalization than that of the engineering stress-strain curve. The real stress-strain curves can be used in the practical engineering of impact stretch to improve its safety.

Keywords: impact stretch, 316L stainless steel, strain rate, real stress-strain, normalization

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9881 Active Bio-Packaging Fabricated from Coated Bagasse Papers with Polystyrene Nanocomposites

Authors: Hesham Moustafa, Ahmed M. Youssef

Abstract:

The demand for green packagingin the food field has been gained increasing attention in recent decades because of its degradability and safely. Thus, this study revealed that the by-product bagasse papers (BPs) derived from sugarcane waste can be decorated with a thin layer of polystyrene (PS) nanocomposites using the spreading approach.Three variable concentrations of TiO2 nanoparticles (i.e. 0.5, 1.0, 1.5 wt.%) were used to fabricate PS nanocomposites. The morphology of coated BP-PS biofilms was examined by X-ray diffraction, Fourier transferred Infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). Moreover, other measurements such as mechanical, thermal stability, flammability, wettability by the contact angle, water vapor, and gas barrier properties were carried out on the fabricated BP-PS biofilms. Most outcomes showed that the major properties were enhanced when the PS nanocomposites were implemented. The use of 1.5 wt.% TiO2 in PS nanocomposite for coated BP-PS biofilm increased the tensile stress by ~ 217 % compared to uncoated BP film. Furthermore, the rate of burning for BP-PS-1.5% film was reduced to ~ 33 mm/min because of the crystallinity of PS and the barrier effect provided by TiO₂ NPs. These coated sheets provide a promising candidate for use in advanced packaging applications.

Keywords: bagasse paper, polystyrene nanocomposites, TiO2 nanoparticles, active packaging, mechanical properties, flammability

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9880 Exergy Analysis of Reverse Osmosis for Potable Water and Land Irrigation

Authors: M. Sarai Atab, A. Smallbone, A. P. Roskilly

Abstract:

A thermodynamic study is performed on the Reverse Osmosis (RO) desalination process for brackish water. The detailed RO model of thermodynamics properties with and without an energy recovery device was built in Simulink/MATLAB and validated against reported measurement data. The efficiency of desalination plants can be estimated by both the first and second laws of thermodynamics. While the first law focuses on the quantity of energy, the second law analysis (i.e. exergy analysis) introduces quality. This paper used the Main Outfall Drain in Iraq as a case study to conduct energy and exergy analysis of RO process. The result shows that it is feasible to use energy recovery method for reverse osmosis with salinity less than 15000 ppm as the exergy efficiency increases twice. Moreover, this analysis shows that the highest exergy destruction occurs in the rejected water and lowest occurs in the permeate flow rate accounting 37% for 4.3% respectively.

Keywords: brackish water, exergy, irrigation, reverse osmosis (RO)

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9879 Effect of Hull-Less Barley Flakes and Malt Extract on Yoghurt Quality

Authors: Ilze Beitane, Evita Straumite

Abstract:

The aim of the research was to evaluate the influence of flakes from biologically activated hull-less barley grain and malt extract on quality of yoghurt during its storage. The results showed that the concentration of added malt extract and storage time influenced the changes of pH and lactic acid in yoghurt samples. Sensory properties-aroma, taste, consistency and appearance-of yoghurt enriched with flakes from biologically activated hull-less barley grain and malt extract changed significantly (p<0.05) during storage. Yoghurt with increased proportion of malt extract had sweeter taste and more flowing consistency. Sensory properties (taste, aroma, consistency, and appearance) of yoghurt samples enriched with 5% flakes from biologically activated hull-less barley grain (YFBG 5%) and 5% flakes from biologically activated hull-less barley grain and 2% malt extract (YFBG 5% ME 2%) did not change significantly during one week of storage.

Keywords: Barley flakes, malt extract, yoghurt, sensory analysis

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9878 Multi-Period Supply Chain Design under Uncertainty

Authors: Amir Azaron

Abstract:

In this research, a stochastic programming approach is developed for designing supply chains with uncertain parameters. Demands and selling prices of products at markets are considered as the uncertain parameters. The proposed mathematical model will be multi-period two-stage stochastic programming, which takes into account the selection of retailer sites, suppliers, production levels, inventory levels, transportation modes to be used for shipping goods, and shipping quantities among the entities of the supply chain network. The objective function is to maximize the chain’s net present value. In order to maximize the chain’s NPV, the sum of first-stage investment costs on retailers, and the expected second-stage processing, inventory-holding and transportation costs should be kept as low as possible over multiple periods. The effects of supply uncertainty where suppliers are unreliable will also be investigated on the efficiency of the supply chain.

Keywords: supply chain management, stochastic programming, multiobjective programming, inventory control

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9877 Speech Enhancement Using Kalman Filter in Communication

Authors: Eng. Alaa K. Satti Salih

Abstract:

Revolutions Applications such as telecommunications, hands-free communications, recording, etc. which need at least one microphone, the signal is usually infected by noise and echo. The important application is the speech enhancement, which is done to remove suppressed noises and echoes taken by a microphone, beside preferred speech. Accordingly, the microphone signal has to be cleaned using digital signal processing DSP tools before it is played out, transmitted, or stored. Engineers have so far tried different approaches to improving the speech by get back the desired speech signal from the noisy observations. Especially Mobile communication, so in this paper will do reconstruction of the speech signal, observed in additive background noise, using the Kalman filter technique to estimate the parameters of the Autoregressive Process (AR) in the state space model and the output speech signal obtained by the MATLAB. The accurate estimation by Kalman filter on speech would enhance and reduce the noise then compare and discuss the results between actual values and estimated values which produce the reconstructed signals.

Keywords: autoregressive process, Kalman filter, Matlab, noise speech

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9876 Modeling the Human Harbor: An Equity Project in New York City, New York USA

Authors: Lauren B. Birney

Abstract:

The envisioned long-term outcome of this three-year research, and implementation plan is for 1) teachers and students to design and build their own computational models of real-world environmental-human health phenomena occurring within the context of the “Human Harbor” and 2) project researchers to evaluate the degree to which these integrated Computer Science (CS) education experiences in New York City (NYC) public school classrooms (PreK-12) impact students’ computational-technical skill development, job readiness, career motivations, and measurable abilities to understand, articulate, and solve the underlying phenomena at the center of their models. This effort builds on the partnership’s successes over the past eight years in developing a benchmark Model of restoration-based Science, Technology, Engineering, and Math (STEM) education for urban public schools and achieving relatively broad-based implementation in the nation’s largest public school system. The Billion Oyster Project Curriculum and Community Enterprise for Restoration Science (BOP-CCERS STEM + Computing) curriculum, teacher professional developments, and community engagement programs have reached more than 200 educators and 11,000 students at 124 schools, with 84 waterfront locations and Out of School of Time (OST) programs. The BOP-CCERS Partnership is poised to develop a more refined focus on integrating computer science across the STEM domains; teaching industry-aligned computational methods and tools; and explicitly preparing students from the city’s most under-resourced and underrepresented communities for upwardly mobile careers in NYC’s ever-expanding “digital economy,” in which jobs require computational thinking and an increasing percentage require discreet computer science technical skills. Project Objectives include the following: 1. Computational Thinking (CT) Integration: Integrate computational thinking core practices across existing middle/high school BOP-CCERS STEM curriculum as a means of scaffolding toward long term computer science and computational modeling outcomes. 2. Data Science and Data Analytics: Enabling Researchers to perform interviews with Teachers, students, community members, partners, stakeholders, and Science, Technology, Engineering, and Mathematics (STEM) industry Professionals. Collaborative analysis and data collection were also performed. As a centerpiece, the BOP-CCERS partnership will expand to include a dedicated computer science education partner. New York City Department of Education (NYCDOE), Computer Science for All (CS4ALL) NYC will serve as the dedicated Computer Science (CS) lead, advising the consortium on integration and curriculum development, working in tandem. The BOP-CCERS Model™ also validates that with appropriate application of technical infrastructure, intensive teacher professional developments, and curricular scaffolding, socially connected science learning can be mainstreamed in the nation’s largest urban public school system. This is evidenced and substantiated in the initial phases of BOP-CCERS™. The BOP-CCERS™ student curriculum and teacher professional development have been implemented in approximately 24% of NYC public middle schools, reaching more than 250 educators and 11,000 students directly. BOP-CCERS™ is a fully scalable and transferable educational model, adaptable to all American school districts. In all settings of the proposed Phase IV initiative, the primary beneficiary group will be underrepresented NYC public school students who live in high-poverty neighborhoods and are traditionally underrepresented in the STEM fields, including African Americans, Latinos, English language learners, and children from economically disadvantaged households. In particular, BOP-CCERS Phase IV will explicitly prepare underrepresented students for skilled positions within New York City’s expanding digital economy, computer science, computational information systems, and innovative technology sectors.

Keywords: computer science, data science, equity, diversity and inclusion, STEM education

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9875 Impact of Weather Conditions on Generalized Frequency Division Multiplexing over Gamma Gamma Channel

Authors: Muhammad Sameer Ahmed, Piotr Remlein, Tansal Gucluoglu

Abstract:

The technique called as Generalized frequency division multiplexing (GFDM) used in the free space optical channel can be a good option for implementation free space optical communication systems. This technique has several strengths e.g. good spectral efficiency, low peak-to-average power ratio (PAPR), adaptability and low co-channel interference. In this paper, the impact of weather conditions such as haze, rain and fog on GFDM over the gamma-gamma channel model is discussed. A Trade off between link distance and system performance under intense weather conditions is also analysed. The symbol error probability (SEP) of GFDM over the gamma-gamma turbulence channel is derived and verified with the computer simulations.

Keywords: free space optics, generalized frequency division multiplexing, weather conditions, gamma gamma distribution

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9874 Conflicts Identification Approach among Stakeholders in Goal-Oriented Requirements Analysis

Authors: Muhammad Suhaib

Abstract:

Requirements Analysis are the most important part of software Engineering for both system application development, and project requirements. Conflicts often arise during the requirements gathering and analysis phase. This research aims to identify conflicts during the requirements gathering phase in software development life cycle, Research, Development, and Technology converted the world into a global village. During requirements elicitation/gathering phase it’s very difficult to understand the main objective of stakeholders, after completion of requirements elicitation task final results are used for Software Requirements Specification (SRS), SRS is the highly important outcome of the requirements analysis phase. this is the foundation between the developers and stakeholders or customers, proposed methodology will be helpful to identify those conflicts in a very easy manner during the initial phase of the project.

Keywords: goal oriented requirements analysis, conflicts identification model, requirements analysis, requirements engineering

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9873 HydroParks: Directives for Physical Environment Interventions Battling Childhood Overweight in Berlin, Germany

Authors: Alvaro Valera Sosa

Abstract:

Background: In recent years, childhood overweight and obesity have become an increasing and challenging phenomenon in Berlin and Germany in general. The highest shares of childhood overweight in Berlin are district localities within the inner city ring with lowest socio-economic levels and the highest number of migration background populations. Most factors explaining overweight and obesity are linked to individual dispositions and nutrition balances. Among various strategies, to target drinking behaviors of children and adolescents has been proven to be effective. On the one hand, encouraging the intake of water – which does not contain energy and thus may support a healthy weight status – on the other hand, reducing the consumption of sugar-containing beverages – which are linked to weight gain and obesity. Anyhow, these preventive approaches have mostly developed into individual or educational interventions widely neglecting environmental modifications. Therefore, little is known on how urban physical environment patterns and features can act as influence factors for childhood overweight. Aiming the development of a physical environment intervention tackling children overweight, this study evaluated urban situations surrounding public playgrounds in Berlin where the issue is evident. It verified the presence and state of physical environmental conditions that can be conducive for children to engage physical activity and water intake. Methods: The study included public playgrounds for children from 0-12 y/o within district localities with the highest prevalence of childhood overweight, highest population density, and highest mixed uses. A systematic observation was realized to describe physical environment patterns and features that may affect children health behavior leading to overweight. Neighborhood walkability for all age groups was assessed using the Walkability for Health framework (TU-Berlin). Playground physical environment conditions were evaluated using Active Living Research assessment sheets. Finally, the food environment in the playground’s pedestrian catchment areas was reviewed focusing on: proximity to suppliers offering sugar-containing beverages, and physical access for 5 y/o children and up to drinking water following the Drinking Fountains and Public Health guidelines of the Pacific Institute. Findings: Out of 114 locations, only 7 had a child population over 3.000. Three with the lowest socio-economic index and highest percentage of migration background were selected. All three urban situations presented similar walkability: large trafficked avenues without buffer bordering at least one side of the playground, and important block to block disconnections for active travel. All three playgrounds rated equipment conditions from good to very good. None had water fountains at the reach of a 5 y/o. and all presented convenience stores and/or fast food outlets selling sugar-containing beverages nearby the perimeter. Conclusion: The three playground situations selected are representative of Berlin locations where most factors that influence children overweight are found. The results delivered urban and architectural design directives for an environmental intervention, used to study children health-related behavior. A post-intervention evaluation could prove associations between designed spaces and children overweight rate reduction creating a precedent in public health interventions and providing novel strategies for the health sector.

Keywords: children overweight, evaluation research, public playgrounds, urban design, urban health

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9872 Long Term Strength Behavior of Hemp-Concrete

Authors: Elie Awwad, Bilal Hamad, Mounir Mabsout, Helmi Khatib

Abstract:

The paper reports test results on the long-term behavior of sustainable hemp-concrete material prepared in research work conducted at the American University of Beirut. The tests results are in terms of compressive and splitting tensile tests conducted on standard 150x300 mm cylinders. A control mix without fibers, one polypropylene-concrete mix, and ten hemp-concrete mixes were prepared with different percentages of industrial hemp fibers and reduced coarse aggregate contents. The objective was to investigate the strength properties of hemp-reinforced concrete at 1.5 years age as compared with control mixes. The results indicated that both the compressive strength and the splitting tensile strength results of all tested cylinders increased as compared with the 28-days values. Also, the difference between the hemp-concrete samples and the control samples at 28 days was maintained at 1.5 years age indicating that hemp fibers did not exhibit any negative effect on the long-term strength properties of concrete.

Keywords: hemp-reinforced concrete, natural fibers, compressive strength, splitting tensile strength

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9871 Body Image Dissatisfaction of Females: A Holistic Therapeutic Approach

Authors: Katy Eleanor Addinall

Abstract:

Women’s body image dissatisfaction is a widespread problem, and it is present in all age groups, on every socioeconomic level, in all occupations, all cultures, and religions. Body image dissatisfaction is a broad term that is used to vary from normal discontent of a woman about one or more of her physical attributes to extreme negative causes, for example, an eating disorder. South African women were examined, and an empirical qualitative study was done to evaluate the women’s thoughts and feelings regarding their bodies. The causes and effects of body image dissatisfaction were examined, and social science literature was used to determine the etiology of body image dissatisfaction, which confirmed that it is multifactorial. A variety of therapeutic aids were studied, and cognitive behavioural therapy appeared to be the most effective. Every woman is an individual with an individual body image and must be approached as an individual holistic being. Thus, a holistic pragmatic model was developed as a possible aid in the woman’s healing process.

Keywords: body, body image, females, woman, therapy, dissatisfaction, holistic, cognitive behavioural therapy

Procedia PDF Downloads 145