Search results for: gravitational forces

Authors: Asyraf Abdul Halim, Mohd Edil Abd Sukor, Obiyathulla Ismath Bacha

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This paper attempts to investigate the capital structure behavior of Shariah compliant firms of various levels as well those firms who are consistently Shariah non-compliant in Malaysia. The paper utilizes a unique dataset of firms of the heterogeneous level of Shariah-compliancy status over a 20 year period from the year 1997 to 2016. The paper focuses on the effects of dynamic forces behind capital structure variation such as the optimal capital structure behavior based on the trade-off, pecking order, market timing and firmly fixed effect models of capital structure. This study documents significant evidence in support of the trade-off theory with a high speed of adjustment (SOA) as well as for the time-invariant firm fixed effects across all Shariah compliance group.

Keywords: capital structure, market timing, trade-off theory, equity risk premium, Shariah-compliant firms

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Authors: Kevin Zhao, Norman J. Horing

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A methodology for cells sorting and circulating tumor cell detection and discrimination is presented in this paper. The technique is based on Dielectrophoresis and microfluidic device theory. Specifically, the sorting of the cells is realized by adjusting the relation among the sedimentation forces, the drag force provided by the fluid, and the Dielectrophortic force that is relevant to the bias voltage applied on the device. The relation leads to manipulation of the elevation of the cells of the same kind to a height by controlling the bias voltage. Once the cells have been lifted to a position next to the bottom of the cell collection channel, the buffer fluid flashes them into the cell collection channel. Repeated elevation of the cells leads to a complete sorting of the cells in the sample chamber. A proof-of-principle example is presented which verifies the feasibility of the methodology.

Keywords: cell sorter, CTC cell, detection and discrimination, dielectrophoresisords, simulation

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Authors: Vigen Arakelian

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This paper deals with the study of devices for displacement of the mould base of blow-molding machines. The displacement of the mould in the studied case is carried out by a linear actuator, which ensures the descent of the mould base and by extension springs, which return the letter in the initial position. The aim of this paper is to study the inverse dynamics of the device for displacement of the mould base of blow-molding machines and to determine its optimum parameters for higher rate of production. In the other words, it is necessary to solve the inverse dynamic problem to find the equation of motion linking applied forces with displacements. This makes it possible to determine the stiffness coefficient of the spring to turn the mold base back to the initial position for a given time. The obtained results are illustrated by a numerical example. It is shown that applying a spring with stiffness returns the mould base of the blow molding machine into the initial position in 0.1 sec.

Keywords: design, mechanisms, dynamics, blow-molding machines

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Authors: Giulia Leoni, Cristina Florio

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The paper aims to investigate the factors driving the increasing alignment of Italian earnings management (EM) research to US research on the same field. After characterizing the progressive similarity of Italian EM research with respect to US one by means of an historical comparison, the paper relies on a subsequent secondary source analysis to detect the possible causes of said alignment. Once identified that the alignment increased along three subsequent periods, the paper analyses and discusses this incremental similarity according to new institutional sociology (NIS) and highlights the presence of different combination of isomorphic pressures that help explaining this incremental similarity. The paper contributes to the institutional literature by providing evidence of isomorphism in academic research; it also contributes to accounting research by indicating the forces that are able to drive change and development in accounting research at national and international level. The paper also enlarges the explanatory value of NIS in alternative contexts, like academic accounting research.

Keywords: accounting research, earnings management, international comparison, Italy, new institutional sociology, US

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Authors: Amy Clark

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To date, the focus of feminist research surrounding men looking at women, with the analysis of how women make sense of looks between women remains limited and scattered. Drawing upon ethnographic data obtained from an on-going research project, this presentation delves into the embodied experiences of female exercisers within a UK ‘working-class’ gym. By exploring the women’s own accounts of their living, breathing and sensing bodies as they exercise, the researcher attempts to understand how they make sense of the gym space, their embodied selves as well as broader constructions of the gendered body. Utilising a feminist phenomenological approach, this research examines the social-structural position of women in a patriarchal system of gender relations, whilst simultaneously acknowledging and analysing the structural, cultural, and historical forces and location, upon individual lived body experiences and gendered embodiment. The discussion is provided on how the gym can be identified as a sexually objectifying environment, and how women make sense and interpret specific ‘gazes’ encountered within the gym.

Keywords: embodiment, feminism, gazes, sociology

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Authors: B. Razmi, F. Rafiee, M. Baziar, A. Saeedi Azizkandi

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In the present research, a series of 3-D finite element numerical modeling was performed to study the effect of system frequency and excitation specifications on the internal forces of the piled raft (PR) system in a dry sand layer. The results of numerical simulations were first compared with those associated with centrifuge tests. The natural frequency of superstructure, modeled on the piled raft foundation, was smaller than the natural frequency of the fixed-base super-structure. This difference was greater for super-structures with higher frequencies. In PR systems, the excitation with a frequency close to the system frequency produced the largest responses. Furthermore, based on the results of presented numerical analyses, ignoring the interactions and characteristics of all components of a pile-raft-structure, may lead to highly uneconomical design.

Keywords: centrifuge test, excitation frequency, natural frequency of super-structure, piled raft foundation, 3-D finite element model

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Authors: M. Volpini, D. Alves, A. Horta, M. Borges, P. Reis

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The gait pattern in people that present motor limitations foment the demand for auxiliary locomotion devices. These artifacts for movement assistance vary according to its shape, size and functional features, following the clinical applications desired. Among the ortheses of lower limbs, the ankle-foot orthesis aims to improve the ability to walk in people with different neuromuscular limitations, although they do not always answer patients' expectations for their aesthetic and functional characteristics. The purpose of this study is to explore the possibility of using new design in additive manufacturer to reproduce the shape and functional features of a ankle-foot orthesis in an efficient and modern way. Therefore, this work presents a study about the performance of the mechanical forces through the analysis of finite elements in an ankle-foot orthesis. It will be demonstrated a study of distribution of the stress on the orthopedic device in orthostatism and during the movement in the course of patient's walk.

Keywords: additive manufacture, new designs, orthoses, finite elements

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Authors: Mohamed Omar

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Steel bracing members are widely used in steel structures to reduce lateral displacement and dissipate energy during earthquake motions. Concentric steel bracing provide an excellent approach for strengthening and stiffening steel buildings. Using these braces the designer can hardly adjust the stiffness together with ductility as needed because of buckling of braces in compression. In this study the use of SMA bracing and steel bracing (Mega) utilized in steel frames are investigated. The effectiveness of these two systems in rehabilitating a mid-rise eight-storey steel frames were examined using time-history nonlinear analysis utilizing Seismo-Struct software. Results show that both systems improve the strength and stiffness of the original structure but due to excellent behavior of SMA in nonlinear phase and under compressive forces this system shows much better performance than the rehabilitation system of Mega bracing.

Keywords: finite element analysis, seismic response, shapes memory alloy, steel frame, mega bracing

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Authors: Rabab Makki

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Bone mineral density and bone metabolism are affected by various factors such as genetic, endocrine, mechanical and nutritional. Our understanding of nutritional influences on bone health is limited because most studies have focused on calcium. This study investigated the dietary factors which are likely t contribute to Osteoporosis in Saudi post-menopausal women, and correlated it with BMD. This is a case controlled study involved 36 postmenopausal Saudi females selected from the Orthopedics and osteoporosis outpatient clinics, and 25 postmenopausal Saudi females as controls from the primary clinic of Military Hospital in Riyadh. The women were diagnosed as osteoporotic based on the BMD measurement at any site (left femur neck, right femur neck, left total hip or right total hip or spine). Both the controls and the Osteoporotics were over 50 years of age and BMI between 31-34 kg/m2 had 2nd degree obesity, and were not free from other problems such as diabetes, hypertension, etc. Subjects (osteoporotics and controls) were interviewed to called data on demographic characterstics, medical history, dietary intake anthropometry (height and weight) bone mineral density. Blood samples were collected from subjects (Osteoporotics and controls). Analysis of serum calcium, vitamin D, phosphate were done at the main laboratory at Military Hospital Riyadh, by the laboratory technician while BMD was determined at the department of Nuclear Medicine by an expert technician and results were interpreted by radiologist.Data on frequency of consumption of animal food (meat, eggs, poultry and fish) and diary foods (milk, yogurt, cheese) of osteoporotic was less than control. In spite of the low intake there was no association with BMD.In general, the vegetables and fruits were consumed less by the osteoporotics than control. The only fruit which had shown a significant positive correlation is banana with right and left hip BMD total probably due to high potassium and minerals content which likely to prevent bone resorption. Mataziz vegetables combination of wheat showed a significant positive correlation with the same site (total right and left hip). Both osteoporotics abd controls were consuming table sugar. (But the sweet intake showed a significant negative correlation with left neck femur BMD, suggesting sucrose increase urinary calcium loss. Both osteoporotic and controls were consuming Arabic coffee. A negative significant correlation between intake of Arabic coffee and BMD of right neck femur of osteoporosis patient was observed. It could be suggested that increased intake of fruits and vegetables, might promote bone density while high intake of coffee and sugars might affect bone density, no significant correlation was observed between BMD at any site and diary product. We can say the major risk factors are inadequate nutrition. Further studies are needed among Saudi population to confirm these results.

Keywords: osteoporosi, Saudia Arabia, Riyadh Armed Forces, postmenopausal women

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Authors: Simone D'Armi

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The notion of the representational soul is widely discussed within the German metaphysical landscape of the 18th century. The enunciation of the notion implies, within the 18th-century German rationalism, a number of generally accepted metaphysical notions. However, in the pre-critical writings of Immanuel Kant, it is possible to identify a critical stance towards this notion. The paper thematizes two central aspects: on the one hand, it discusses the notion of the vis of the representative soul, and on the other, it addresses the question of the fundamental forces ( Grundkraefte) of the soul. The aim of the present paper is to show how Kant, in the Nova Dilucidatio and in his Lectures on Metaphysics, probably delivered in the mid-1770s, despite the Wolffian terminology he employed in the field of psychology, criticizes the central aspects connected with the notion of the soul as a representative force. Beginning with a critical analysis of the relationship between Kantian ideas and those of some key exponents of German metaphysical rationalism, it emerges how the Kantian position stands as an alternative to its own historical context.

Keywords: German metaphysics, soul, power, pre-critical philosophy

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Authors: M. R. Akbari, P. Soleimani, R. Khalili, Sara Akbari

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Analyzing and modeling the vibrational behavior of arched bridges during the earthquake in order to decrease the exerted damages to the structure is a very hard task to do. This item has been done analytically in the present paper for the first time. Due to the importance of building arched bridges as a great structure in the human being civilization and its specifications such as transferring vertical loads to its arcs and the lack of bending moments and shearing forces, this case study is devoted to this special issue. Here, the nonlinear vibration of arched bridges has been modeled and simulated by an arched beam with harmonic vertical loads and its behavior has been investigated by analyzing a nonlinear partial differential equation governing the system. It is notable that the procedure has been done analytically by AGM (Akbari, Ganji Method). Furthermore, comparisons have been made between the obtained results by numerical Method (rkf-45) and AGM in order to assess the scientific validity.

Keywords: new method (AGM), arched beam bridges, angular frequency, harmonic loads

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Authors: Rana Nasiri, Hamid Vahidkia

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Recently, most courts in democratic nations were hesitant to consider foreign and international law. Their approach was to steer clear of using foreign sources of law that conflicted with their own government's stance. Numerous legal experts consider turning to foreign and international law unsuitable. However, those who advocate for using external sources of law also believe that relying on foreign and international law will always be in conflict with the importance of national sovereignty. Therefore, the academic discussion revolves around the commonly known broader debate on ‘the counter-majoritarian difficulty’. This article challenges the idea of tension. It suggests that in many democratic nations' legal systems, including those in the U.S., using foreign and international law can help strengthen domestic democratic processes by protecting them from outside economic, political, and legal influences. Citing international law supports domestic democratic processes and regains national sovereignty from various globalization forces. In other words, national courts must consider foreign and international law to uphold their national political institutions and protect their own status in relation to political branches.

Keywords: international law, social science, US, democracy, politics

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Authors: Thanaporn Chaimongkol

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The objective of this research was aimed to examine the factors that influence the development of community leadership strategies to further develop the career regarding the Benjarong pottery products in eight upper central provinces, Thailand. The sample included (1) 1200 Benjarong pottery operators, (2) 30 involved representatives at both the policy level and support, and (3) OTOP network of 24 people. In this quantitative study, investigating data was conducted on individual session basis. The research instruments used included questionnaires and interview. The results showed that the components of the development of the community leadership strategies for career development of the Benjarong pottery products in eight upper central provinces were high overall; the Five Competitive Forces were of the highest average, followed by bargaining power of suppliers, and McKinsey 7's framework, respectively; where the highest average was strategy.

Keywords: community leadership, strategy development, Benjarong Pottery, 8 upper central provinces

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Authors: Mohammed Saif Al-Saidi, John P. T. Mo

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Modern engineering assets are complex and very high in value. They are expected to function for years to come, with ability to handle the change in technology and ageing modification. The aging of an engineering asset and continues increase of vendors and contractors numbers forces the asset operation management (or Owner) to design an asset system which can capture these changes. Furthermore, an accurate performance measurement and risk evaluation processes are highly needed. Therefore, this paper explores the nature of the asset management system performance evaluation for an engineering asset based on the System Support Engineering (SSE) principles. The research work explores the asset support system from a range of perspectives, interviewing managers from across a refinery organisation. The factors contributing to complexity of an asset management system are described in context which clusters them into several key areas. It is proposed that SSE framework may then be used as a tool for analysis and management of asset. The paper will conclude with discussion of potential application of the framework and opportunities for future research.

Keywords: asset management, performance, evaluation, modern engineering, System Support Engineering (SSE)

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Authors: Orhan Sezgin, Mehmet Kursad Ordu

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In today’s business world, among a number of forces, employees are seen as the most important components in order to survive and achieve organizational goals successfully. Improving the performance and effectiveness of the employees that also are called the “human capital” is one of the most important responsibilities of today’s managers. Managers are expected to provide a workplace to improve the employee’s performance and commitment. Improving the performance and effectiveness of the employees is one of the most significant responsibilities of managers. They are expected to provide a workplace to improve employee’s performance and commitment. This study has concentrated on the exploring of the associations among the basic concepts of organizational behavior science including organizational culture, organizational justice behavior. These concepts play significant roles both on the improvement of employees and the organizations.

Keywords: organization culture, organizational justice, procedural justice, distributive justice

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Authors: M. A. El-Sayed, S. A. Aziz

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Centrifugal casting is a standard casting technique for the manufacture of hollow, intricate and sound castings without the use of cores. The molten metal or alloy poured into the rotating mold forms a hollow casting as the centrifugal forces lift the liquid along the mold inner surface. The rotational speed of the die was suggested to greatly affect the manner in which the molten metal flows within the mould and consequently the probability of the formation of a uniform cylinder. In this work the flow of the liquid metal at various speeds and its effect during casting were studied. The results suggested that there was a critical range for the speed, within which the produced castings exhibited best uniformity and maximum mechanical properties. When a mould was rotated at speeds below or beyond the critical range defects were found in the final castings, which affected the uniformity and significantly lowered the mechanical properties.

Keywords: centrifugal casting, rotational speed, critical speed range, mechanical properties

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Authors: Joaquim Rubens Fontes-Filho, Felipe Buchbinder, Marcelo Desterro

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The study aims to identify the effects of an economic recession on the compensation of executives of listed companies. Market-based and labor environment explanations have received particular attention, both to explain the reasons for a growth in this compensation and to indicate that they may increase agency problems rather than mitigate them. In this sense, labor forces, especially related to the market for executives, contribute to defining the terms of compensation packages and represent a significant external control mechanism to moderate agency problems, but may be of little effect if the executives are entrenched and concentrate enough power to have a say in his/her compensation. Based on a five-year data panel related to executive compensation in 250 listed companies in Brazil, we examine whether the economic recession in the last two years produced any impact in this compensation, controlling for the sector and level of governance of the company.

Keywords: agency problems, executive compensation, control mechanisms, corporate governance

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Authors: Andrew Gray, Zhibing Zhang

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The ability for consumer products to deliver a sustained perfume response can be a key driver for a variety of applications. Many compounds in perfume oils are highly volatile, meaning they readily evaporate once the product is applied, and the longevity of the scent is poor. Perfume capsules have been introduced as a means of abating this evaporation once the product has been delivered. The impermeable capsules are aimed to be stable within the formulation, and remain intact during delivery to the desired substrate, only rupturing to release the core perfume oil through application of mechanical force applied by the consumer. This opens up the possibility of obtaining an olfactive response hours, weeks or even months after delivery, depending on the nature of the desired application. Tailoring the properties of the polymeric capsules to better address the needs of the application is not a trivial challenge and currently design of capsules is largely done by trial and error. The aim of this work is to have more predictive methods for capsule design depending on the consumer application. This means refining formulations such that they rupture at the right time for the specific consumer application, not too early, not too late. Finding the right balance between these extremes is essential if a benefit is sought with respect to neat addition of perfume to formulations. It is important to understand the forces that influence capsule rupture, first, by quantifying the magnitude of these different forces, and then by assessing bulk rupture in real-world applications to understand how capsules actually respond. Samples were provided by an industrial partner and the mechanical properties of individual capsules within the samples were characterized via a micromanipulation technique, developed by Professor Zhang at the University of Birmingham. The capsules were synthesized such as to change one particular physicochemical property at a time, such as core: wall material ratio, and the average size of capsules. Analysis of shell thickness via Transmission Electron Microscopy, size distribution via the use of a Mastersizer, as well as a variety of other techniques confirmed that only one particular physicochemical property was altered for each sample. The mechanical analysis was subsequently undertaken, showing the effect that changing certain capsule properties had on the response under compression. It was, however, important to link this fundamental mechanical response to capsule performance in real-world applications. As such, the capsule samples were introduced to a formulation and exposed to full scale stresses. GC-MS headspace analysis of the perfume oil released from broken capsules enabled quantification of what the relative strengths of capsules truly means for product performance. Correlations have been found between the mechanical strength of capsule samples and performance in terms of perfume release in consumer applications. Having a better understanding of the key parameters that drive performance benefits the design of future formulations by offering better guidelines on the parameters that can be adjusted without worrying about the performance effects, and singles out those parameters that are essential in finding the sweet spot for capsule performance.

Keywords: consumer products, mechanical and physicochemical properties, perfume capsules, rupture behaviour

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Authors: Liuyu Zhang, Di Mo, Qiang Yan, Min Liu

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As the important equipment in the construction field, cuplock scaffold plays an important role in the construction process. As a scaffold connecting member, cuplock joint is of great importance. In order to explore the rotational stiffness nonlinear characteristics changing features of different structural forms of cuplock joint in different tightening torque condition under different conditions of load, ANSYS is used to establish four kinds of cuplock joint models with different forces to simulate the real force situation. By setting the different load conditions which means the cuplock is loaded at a certain distance from the cuplock joint in a certain direction until the cuplock is damaged and considering the gap between the cross bar joint and the vertical bar, the differences in the influence of the structural form and tightening torque on the rotation stiffness of the cuplock under different load conditions are compared. It is significantly important to improve the accuracy of calculating bearing capacity and stability of the cuplock steel pipe scaffold.

Keywords: cuplock joint, highway tunnel, non-linear characteristics, rotational stiffness, scaffold stability, theoretical analysis

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Authors: Yulia Totskaya

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Nowadays, society is in a postindustrial/informational phase of its development. Certain changes have occurred in different parts of society life as a result of the social reality transformations due to the influence of changes in the productive forces. As a result, the personality has received autonomy and independence, as in her or his hands appeared new means of production–information, knowledge, creativity. In such a society, there is a new middle class, which is called meritocratic. It consists of personalities, who are engaged in highly intelligent, creative work; who independently pursue their own well-being and status; who are active in the economic and social spheres. At the forefront there are such qualities as independence, commitment and self-actualization. This modern, intellectual and sovereign personality is no longer in need of care. The role of management has transformed from a paternalistic to the "service", which is aimed at creating the conditions for citizens’ self-realization to meet their needs through the rendering of public services. Such society alterations motivate the need to change the key parameters of social management, which are identified in this article on the basis of the postindustrial society key features.

Keywords: informational society, postindustrial society, postindustrial sociality, public services, social management

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Authors: Chungkuk Jin, Moohyun Kim, Woo Chul Chung

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This paper presents global performance and dynamic behaviors of a discrete-pontoon-type floating bridge with mooring lines in time domain under wind and wave excitations. The structure is designed for long-distance and deep-water crossing and consists of the girder, columns, pontoons, and mooring lines. Their functionality and behaviors are investigated by using elastic-floater/mooring fully-coupled dynamic simulation computer program. Dynamic wind, first- and second-order wave forces, and current loads are considered as environmental loads. Girder’s dynamic responses and mooring tensions are analyzed under different analysis methods and environmental conditions. Girder’s lateral responses are highly influenced by the second-order wave and wind loads while the first-order wave load mainly influences its vertical responses.

Keywords: floating bridge, mooring line, pontoon, wave excitation

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Authors: Khanita Tumphasuwan

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The Wualai community of Northern Thailand represents important intellectual and social capital and their silver handicraft products are desirable tourist souvenirs within Chiang Mai Province. This community has been in danger of losing this social and intellectual capital due to the application of an improper tool, the Scottish Enterprise model of clustering. This research aims to analyze and increase its competitive advantages for preventing the loss of social and intellectual capital. To improve the Wualai’s competitive advantage, analysis is undertaken using a Porterian cluster approach, including the diamond model, five forces model and cluster mapping. Research results suggest that utilizing the community’s Buddhist beliefs can foster collaboration between community members and is the only way to improve cluster effectiveness, increase competitive advantage, and in turn conserve the Wualai community.

Keywords: industry clustering, silver handicraft, competitive advantage, intellectual capital, social capital

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Authors: Dursun Kalebaşi

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When we examine the history of mankind (from the past up to the present), we see that millions of people died because of the wars. Especially, since the beginning of 19th century, the increase of the human death rate is caused mostly by the regional conflicts and natural disasters rather than the wars. From that point of view, the biggest threat humanity face today is temperature increase and climate change that started to emerge in recent years. When we take into account the natural disasters on one hand and refuges that flee from regional conflicts on the other, it stands out as a dramatic situation because of the huge human losses. In this context, most of the countries started to give more importance to Search and Rescue (SAR) operations to stop the loss of lives or decrease the death rate. This article will tell about the SAR activities in Turkey since 2000 and discuss the Turkey’s contributions to Rescue Missions after the natural disasters in different parts of the world. Moreover, there will be some new highlights to a more habitable and more peaceful world through the SAR missions.

Keywords: search and rescue, natural disasters, migration and world peace, Turkish army forces

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Authors: Maamar Ali Saud Al Tobi, Geraint Bevan, K. P. Ramachandran, Peter Wallace, David Harrison

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Centrifugal pumps are complex machines which can experience different types of fault. Condition monitoring can be used in centrifugal pump fault detection through vibration analysis for mechanical and hydraulic forces. Vibration analysis methods have the potential to be combined with artificial intelligence systems where an automatic diagnostic method can be approached. An automatic fault diagnosis approach could be a good option to minimize human error and to provide a precise machine fault classification. This work aims to introduce an approach to centrifugal pump fault diagnosis based on artificial intelligence and genetic algorithm systems. An overview of the future works, research methodology and proposed experimental setup is presented and discussed. The expected results and outcomes based on the experimental work are illustrated.

Keywords: centrifugal pump setup, vibration analysis, artificial intelligence, genetic algorithm

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Authors: O. Hinrichs, H. Franz, G. Reiter

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Electron guns have a key function in a series of thermal processes, like EB (electron beam) melting, evaporation or welding. These techniques need a high-intensity continuous electron beam that defocuses itself due to high space charge forces. A proper beam transport throughout the magnetic focusing system can be ensured by a space charge compensation via residual gas ions. The different pressure stages in the EB gun cause various degrees of compensation. A numerical model was installed to simulate realistic charge distributions within the beam by using CST-Particle Studio code. We will present current status of beam dynamic simulations. This contribution will focus on the creation of space charge ions and their influence on beam and gun components. Furthermore, the beam transport in the gun will be shown for different beam parameters. The electron source allows to produce beams with currents of 3 A to 15 A and energies of 40 keV to 45 keV.

Keywords: beam dynamic simulation, space charge compensation, thermionic electron source, EB melting, EB thermal processing

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Authors: A. A. A. Aboalnour, Ahmed M. Amasaib, Mohammed-Almujtaba A. Mohammed-Farah, Abdelhakam, A. Noreldien

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This paper presents a design and study of Parabolic Trough Solar Collector (PTC). Mathematical models were used in this work to find the direct and reflected solar radiation from the air layer on the surface of the earth per hour based on the total daily solar radiation on a horizontal surface. Also mathematical models had been used to calculate the radiation of the tilted surfaces. Most of the ingredients used in this project as previews data required on several solar energy applications, thermal simulation, and solar power systems. In addition, mathematical models had been used to study the flow of the fluid inside the tube (receiver), and study the effect of direct and reflected solar radiation on the pressure, temperature, speed, kinetic energy and forces of fluid inside the tube. Finally, the mathematical models had been used to study the (PTC) performances and estimate its thermal efficiency.

Keywords: CFD, experimental, mathematical models, parabolic trough, radiation

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Authors: Madhavi T., Sireesha Sakhamuri, Hema Sri A., Harika K.

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Today as technological advancements are taking place, these advancements are being used by the armed forces to reduce the risk of their losses and to defeat their enemies. The development of sophisticated technology relies mostly on the use of high- tech weapons or machinery. Robotics is one of the hot spheres of the modern age in which nations concentrate on the state of war and peace for military purposes. They have been in use for demining and rescue operations for some time now but are being propelled by using them for combat and spy missions. This project focuses on creating a LoRa-based spying robot with a wireless IP camera attached to it that can rising the human target. This robot transmits the signal via an IP camera to the base station. One of this project’s major applications can be analyzed using a PC that can be used to control the robot’s movement. The robot sends the signal through the LoRa transceiver at the base station to the LoRa transceiver mounted on the robot. With this function, the, robot can relay videos in real- time along with anti-collision capabilities and the enemies in the war zone cannot recognize them. More importantly, this project focuses on increasing communication using LoRa.

Keywords: lora, IP cam, metal detector, laser shoot

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Authors: Boughedaoui Rachid, Belaidi Idir, Ouali Mohamed

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The formatting by removal of material remains an indispensable means for obtaining different forms of pieces. The objective of this work is to study the influence of parameters of the vibratory regime of the system PTM 'Piece-Tool-Machine, in the case of the machining of the thin pieces on the surface finish. As a first step, an analytical study of essential dynamic models 2D slice will be presented. The stability lobes will be thus obtained. In a second step, a characterization of PTM system will be realized. This system will be instrumented with accelerometric sensors but also a laser vibrometer so as to have the information closer to the cutting area. Dynamometers three components will be used for the analysis of cutting forces. Surface states will be measured and the condition of the cutting edge will be visualized thanks to a binocular microscope coupled to a data acquisition system. This information will allow quantifying the influence of chatter on the dimensional quality of the parts. From lobes stabilities previously determined experimental validation allow for the development a method for detecting of the phenomenon of chatter and so an approach will be proposed.

Keywords: chatter, dynamic, milling, lobe stability

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Authors: Khaoula Hidouri, Ali Benhmidene, Bechir Chouachi, Dhananjay R. Mishra, Ammar Houas

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Activated carbon DSAC36-24 iy is adsorbent materials, characterized by a specific surface area of 548.13 m²g⁻¹. Their manufacture uses the natural raw materials like the nucleus of dates. In this study the treatment is done in two stages: A chemical treatment by H₃PO₄ followed by a physical treatment under nitrogen for 1 hour then under stream of CO₂ for 24 hours. A characterization of the various parameters was determined such as the measurement of the specific surface area, determination of pHPZC, bulk density, iodine value. The study of the adsorption of organic molecules (hydroquinone, paranitrophenol, 2,4-dinitrophenol, 2,4,6-trinitrophenol) indicates that the adsorption phenomena are essentially due to the van der Waals interaction. In the case of organic molecules carrying the polar substituents, the existence of hydrogen bonds is also proved by the donor-acceptor forces. The study of the pH effect was done with modeling by different models (Langmuir, Freundlich, Langmuir-Freundlich, Redlich-Peterson), a kinetic treatment is also followed by the application of Lagergren, Weber, Macky.

Keywords: adsoprtion ishoterms, adsorption kinetics, DSAC36-24, organic molecule

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Authors: Takashi Shimizu, Tomoaki Hashimoto

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Recently, crystal growth technologies have made progress by the requirement for the high quality of crystal materials. To control the crystal growth dynamics actively by external forces is useuful for reducing composition non-uniformity. In this study, a control method based on model predictive control using thermal inputs is proposed for crystal growth dynamics of semiconductor materials. The control system of crystal growth dynamics considered here is governed by the continuity, momentum, energy, and mass transport equations. To establish the control method for such thermal fluid systems, we adopt model predictive control known as a kind of optimal feedback control in which the control performance over a finite future is optimized with a performance index that has a moving initial time and terminal time. The objective of this study is to establish a model predictive control method for crystal growth dynamics of semiconductor materials.

Keywords: model predictive control, optimal control, process control, crystal growth

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