Search results for: internal loop airlift
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2993

Search results for: internal loop airlift

803 Educational Turn towards Digitalization by Changing Leadership, Networks and Qualification Concepts

Authors: Patricia Girrbach

Abstract:

Currently, our society is facing a new and incremental upheaval technological revolution named digitalization. In order to face the relating challenges organizations have to be prepared. They need appropriate circumstances in order to cope with current issues concerning digital transformation processes. Nowadays digitalization emerged as top issues for companies and business leaders. In this context, it is a pressure on companies to have a positive, productive digital culture. And indeed, Organizations realize that they need to address this important issue. In this context 87 percent of organizations quote culture and engagement as one of their top challenges in terms of any change process, but especially in terms of the digital turn. Executives can give their company a competitive advantage and attract top talent by having a strong workplace culture that supports digitalization. Many current studies attest that fact. Digital-oriented companies can hire more easily, they have the lowest voluntary turnover rates, deliver better customer service, and are more profitable over the long run. Based on this background it is important to provide companies starting points and practical measurements how to reach this goal. The major findings are that firms need to make sense out of digitalization. In this context, they should focus on internal but also on external stakeholders. Furthermore, they should create certain working conditions and they should support the qualification of employees, e.g. by Virtual Reality. These measurements can create positive experiences in terms of digitalization in order to ensure the support of stuff in terms of the digital turn. Based on several current studies and literature research this paper provides concrete measurements for companies in order to enable the digital turn. Therefore, the aim of this paper is providing possible practical starting points which support both the education of employees by digitalization as well as the digital turn itself within the organization.

Keywords: digitalization, industry 4.0, education 4.0, virtual reality

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802 Collapse Analysis of Planar Composite Frame under Impact Loads

Authors: Lian Song, Shao-Bo Kang, Bo Yang

Abstract:

Concrete filled steel tubular (CFST) structure has been widely used in construction practices due to its superior performances under various loading conditions. However, limited studies are available when this type of structure is subjected to impact or explosive loads. Current methods in relevant design codes are not specific for preventing progressive collapse of CFST structures. Therefore, it is necessary to carry out numerical simulations on CFST structure under impact loads. In this study, finite element analyses are conducted on the mechanical behaviour of composite frames which composed of CFST columns and steel beams subject to impact loading. In the model, CFST columns are simulated using finite element software ABAQUS. The model is verified by test results of solid and hollow CFST columns under lateral impacts, and reasonably good agreement is obtained through comparisons. Thereafter, a multi-scale finite element modelling technique is developed to evaluate the behaviour of a five-storey three-span planar composite frame. Alternate path method and direct simulation method are adopted to perform the dynamic response of the frame when a supporting column is removed suddenly. In the former method, the reason for column removal is not considered and only the remaining frame is simulated, whereas in the latter, a specific impact load is applied to the frame to take account of the column failure induced by vehicle impact. Comparisons are made between these two methods in terms of displacement history and internal force redistribution, and design recommendations are provided for the design of CFST structures under impact loads.

Keywords: planar composite frame, collapse analysis, impact loading, direct simulation method, alternate path method

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801 Characteristics of Meiofaunal Communities in Intertidal Habitats Along Albanian Adriatic Sea Coast

Authors: Fundime Miri, Emanuela Sulaj

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Benthic ecosystems constitute important ecological habitats, providing fundamental services for spawning, foraging, and sheltering aquatic organisms. Benthic faunal communities are characterized by a large biological diversity, supported by a great physical variety of benthic habitats. Until late, the study of meiobenthic communities in Albania has been neglectedthus excluding an important component of benthos. The present study aims to bring characteristics of distribution pattern of meiofaunal communities with further focus on nematode genus-based diversity from different intertidal habitats along Albanian Adriatic Sea Coast. The investigation area is extended from Shkodra to Vlora District, including six sandy sampling sites in beaches and areas near river estuaries. Sediment samples were collected manually in low intertidal zone by using a cylindrical corer, with an internal diameter of 5 cm. The richness onmeiofaunalmajor taxon level did not show any significant change between different sampling sites compare to significant changes in nematode diversity at genus level, with distinct nematode assemblages per sampling sites and presence of exclusive genera. All meiofaunal communities under study were dominated by nematodes. Further assessment of functional diversity on nematode assemblages exhibited changes as well on trophic groups and life strategies due to diverse feeding behaviors and c-p values of nematode genera. This study emphasize the need for lower level taxonomic identification of meiofaunal organisms and extending of ecological assessments on trophic diversity and life strategies to understanding functional consequences.

Keywords: benthos, meiofauna, nematode genus-based diversity, functional diversity, intertidal, albanian adriatic coast

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800 Triplet Shear Tests on Retrofitted Brickwork Masonry Walls

Authors: Berna Istegun, Erkan Celebi

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The main objective of this experimental study is to assess the shear strength and the crack behavior of the triplets built of perforated brickwork masonry elements. In order to observe the influence of shear resistance and energy dissipating before and after retrofitting applications by using the reinforcing system, static-cyclic shear tests were employed in the structural mechanics laboratory of Sakarya University. The reinforcing system is composed of hybrid multiaxial seismic fabric consisting of alkali resistant glass and polypropylene fibers. The plaster as bonding material used in the specimen’s retrofitting consists of expanded glass granular. In order to acquire exact measuring data about the failure behavior of the two mortar joints under shear stressing, vertical load-controlled cylinder having force capacity of 50 kN and loading rate of 1.5 mm/min. with an internal inductive displacement transducers is carried out perpendicular to the triplet specimens. In this study, a total of six triplet specimens with textile reinforcement were prepared for these shear bond tests. The three of them were produced as single-sided reinforced triplets with seismic fabric, while the others were strengthened on both sides. In addition, three triplet specimens without retrofitting and plaster were also tested as reference samples. The obtained test results were given in the manner of force-displacement relationships, ductility coefficients and shear strength parameters comparatively. It is concluded that two-side seismic textile applications on masonry elements with relevant plaster have considerably increased the sheer force resistance and the ductility capacity.

Keywords: expanded glass granular, perforated brickwork, retrofitting, seismic fabric, triplet shear tests

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799 The New Insight about Interspecies Transmission of Iranian H9N2 Influenza Viruses from Avian to Human

Authors: Masoud Soltanialvar, Ali Bagherpour

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Documented cases of human infection with H9N2 avian influenza viruses, first detected in 1999 in Hong Kong and China, indicate that these viruses can be directly transmitted from birds to humans. In this study, we characterized the mutation in the Hemagglutinin (HA) genes and proteins that correlates with a shift in affinity of the Hemagglutinin (HA) protein from the “avian” type sialic receptors to the “human” type in 10 Iranian isolates. We delineated the genomes and receptor binding profile of HA gene of some field isolates and established their phylogenetic relationship to the other Asian H9N2 sub lineages. A total of 1200 tissue samples collected from 40 farms located in various states of Iran during 2008 – 2010 as part of a program to monitor Avian Influenza Viruses (AIV) infection. To determine the genetic relationship of Iranian viruses, the Hemagglutinin (HA) genes from ten isolates were amplified and sequenced (by RT-PCR method). Nucleotide sequences (orf) of the (HA) genes were used for phylogenetic tree construction. Deduced amino acid sequences showed the presence of L226 (234 in H9 numbering) in all ten Iranian isolates which indicates a preference to binding of α (2–6) sialic acid receptors, so these Iranian H9N2 viruses have the potential to infect human beings. These isolates showed high degree of homology with 2 human H9N2 isolates A/HK/1073/99, A/HK/1074/99. Phylogenetic analysis of showed that all the HA genes of the Iranian H9N2 viruses fall into a single group within a G1-like sublineage which had contributed as donor of six internal genes to H5N1 highly pathogenic avian influenza. The results of this study indicated that all Iranian viruses have the potential to emerge as highly pathogenic influenza virus, and considering the homology of these isolates with human H9N2 strains, it seems that the potential of these avian influenza isolates to infect human should not be overlooked.

Keywords: influenza virus, hemagglutinin, neuraminidase, Iran

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798 Design & Development of a Static-Thrust Test-Bench for Aviation/UAV Based Piston Engines

Authors: Syed Muhammad Basit Ali, Usama Saleem, Irtiza Ali

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Internal combustion engines have been pioneers in the aviation industry, use of piston engines for aircraft propulsion, from propeller-driven bi-planes to turbo-prop, commercial, and cargo airliners. To provide an adequate amount of thrust piston engine rotates the propeller at a specific rpm, allowing enough mass airflow. Thrust is the only forward-acting force of an aircraft that helps heavier than air bodies to fly, depending on the mathematical model and variables included in that with the correct measurement. Test-benches have been a bench-mark in the aerospace industry to analyse the results before a flight, having paramount significance in reliability and safety engineering, depending on the mathematical model and variables included in that with the correct measurement. Calculation of thrust from a piston engine also depends on environmental changes, the diameter of the propeller, and the density of air. The project would be centered on piston engines used in the aviation industry for light aircraft and UAVs. A static thrust test bench involves various units, each performing a designed purpose to monitor and display. Static thrust tests are performed on the ground, and safety concerns hold paramount importance. The execution of this study involves research, design, manufacturing, and results based on reverse engineering initiating from virtual design, analytical analysis, and simulations. The final evaluation of results gathered from various methods such as co-relation between conventional mass-spring and digital loadcell. On average, we received 17.5kg of thrust (25+ engine run-ups – around 40 hours of engine run), only 10% deviation from analytically calculated thrust –providing 90% accuracy.

Keywords: aviation, aeronautics, static thrust, test bench, aircraft maintenance

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797 Impact of Different Fuel Inlet Diameters onto the NOx Emissions in a Hydrogen Combustor

Authors: Annapurna Basavaraju, Arianna Mastrodonato, Franz Heitmeir

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The Advisory Council for Aeronautics Research in Europe (ACARE) is creating awareness for the overall reduction of NOx emissions by 80% in its vision 2020. Hence this promotes the researchers to work on novel technologies, one such technology is the use of alternative fuels. Among these fuels hydrogen is of interest due to its one and only significant pollutant NOx. The influence of NOx formation due to hydrogen combustion depends on various parameters such as air pressure, inlet air temperature, air to fuel jet momentum ratio etc. Appropriately, this research is motivated to investigate the impact of the air to fuel jet momentum ratio onto the NOx formation in a hydrogen combustion chamber for aircraft engines. The air to jet fuel momentum is defined as the ratio of impulse/momentum of air with respect to the momentum of fuel. The experiments were performed in an existing combustion chamber that has been previously tested for methane. Premix of the reactants has not been considered due to the high reactivity of the hydrogen and high risk of a flashback. In order to create a less rich zone of reaction at the burner and to decrease the emissions, a forced internal recirculation flow has been achieved by integrating a plate similar to honeycomb structure, suitable to the geometry of the liner. The liner has been provided with an external cooling system to avoid the increase of local temperatures and in turn the reaction rate of the NOx formation. The injected air has been preheated to aim at so called flameless combustion. The air to fuel jet momentum ratio has been inspected by changing the area of fuel inlets and keeping the number of fuel inlets constant in order to alter the fuel jet momentum, thus maintaining the homogeneity of the flow. Within this analysis, promising results for a flameless combustion have been achieved. For a constant number of fuel inlets, it was seen that the reduction of the fuel inlet diameter resulted in decrease of air to fuel jet momentum ratio in turn lowering the NOx emissions.

Keywords: combustion chamber, hydrogen, jet momentum, NOx emission

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796 Reimagining the Management of Telco Supply Chain with Blockchain

Authors: Jeaha Yang, Ahmed Khan, Donna L. Rodela, Mohammed A. Qaudeer

Abstract:

Traditional supply chain silos still exist today due to the difficulty of establishing trust between various partners and technological barriers across industries. Companies lose opportunities and revenue and inadvertently make poor business decisions resulting in further challenges. Blockchain technology can bring a new level of transparency through sharing information with a distributed ledger in a decentralized manner that creates a basis of trust for business. Blockchain is a loosely coupled, hub-style communication network in which trading partners can work indirectly with each other for simpler integration, but they work together through the orchestration of their supply chain operations under a coherent process that is developed jointly. A Blockchain increases efficiencies, lowers costs, and improves interoperability to strengthen and automate the supply chain management process while all partners share the risk. Blockchain ledger is built to track inventory lifecycle for supply chain transparency and keeps a journal of inventory movement for real-time reconciliation. State design patterns are used to capture the life cycle (behavior) of inventory management as a state machine for a common, transparent and coherent process which creates an opportunity for trading partners to become more responsive in terms of changes or improvements in process, reconcile discrepancies, and comply with internal governance and external regulations. It enables end-to-end, inter-company visibility at the unit level for more accurate demand planning with better insight into order fulfillment and replenishment.

Keywords: supply chain management, inventory trace-ability, perpetual inventory system, inventory lifecycle, blockchain, inventory consignment, supply chain transparency, digital thread, demand planning, hyper ledger fabric

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795 The Construct of Personal Choice within Individual Language Shift: A Phenomenological Qualitative Study

Authors: Kira Gulko Morse

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Choosing one’s primary language may not be as common as choosing an additional foreign language to study or use during travel. In some instances, however, it becomes a matter of internal personal struggle, as language is tied not only to specific circumstances but also to human background and identity. This phenomenological qualitative study focuses on the factors affecting the decision of a person to undergo a language shift. Specifically, it considers how these factors relate to identity negotiation and expression. The data for the study include the analysis of published autobiographical narratives and personal interviews conducted using the Responsive Interviewing model. While research participants come from a variety of geographical locations and have used different reasons for undergoing their individual language shift, the study identifies a number of common features shared by all the participants. Specifically, while all the participants have been able to maintain their first language to varying degrees of proficiency, they have all completed the shift to establish a primary language different from their first. Additionally, the process of self-identification is found to be directly connected to the phenomenon of language choice for each of the participants. The findings of the study further tie the phenomenon of individual language shift to a more comprehensive issue of individual life choices – ethnic revival, immigration, and inter-cultural marriage among others. The study discusses varying language roles and the data indicate that language shift may occur whether it is a symbolic driving force or a secondary means in fulfilling a set life goal. The concept of language addition is suggested as an alternative to the arbitrariness of language shift. Thus, instead of focusing on subtractive bilingualism or language loss, the emphasis becomes the integration of languages within the individual. The study emphasizes the importance of the construct of personal choice in its connection to individual language shift. It places the focus from society onto an individual and the ability of an individual to make decisions in matters of linguistic identification.

Keywords: choice theory, identity negotiation, language shift, psycholinguistics

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794 Proactive Change or Adaptive Response: A Study on the Impact of Digital Transformation Strategy Modes on Enterprise Profitability From a Configuration Perspective

Authors: Jing-Ma

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Digital transformation (DT) is an important way for manufacturing enterprises to shape new competitive advantages, and how to choose an effective DT strategy is crucial for enterprise growth and sustainable development. Rooted in strategic change theory, this paper incorporates the dimensions of managers' digital cognition, organizational conditions, and external environment into the same strategic analysis framework and integrates the dynamic QCA method and PSM method to study the antecedent grouping of the DT strategy mode of manufacturing enterprises and its impact on corporate profitability based on the data of listed manufacturing companies in China from 2015 to 2019. We find that the synergistic linkage of different dimensional elements can form six equivalent paths of high-level DT, which can be summarized as the proactive change mode of resource-capability dominated as well as adaptive response mode such as industry-guided resource replenishment. Capacity building under complex environments, market-industry synergy-driven, forced adaptation under peer pressure, and the managers' digital cognition play a non-essential but crucial role in this process. Except for individual differences in the market industry collaborative driving mode, other modes are more stable in terms of individual and temporal changes. However, it is worth noting that not all paths that result in high levels of DT can contribute to enterprise profitability, but only high levels of DT that result from matching the optimization of internal conditions with the external environment, such as industry technology and macro policies, can have a significant positive impact on corporate profitability.

Keywords: digital transformation, strategy mode, enterprise profitability, dynamic QCA, PSM approach

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793 Theoretical Evaluation of Minimum Superheat, Energy and Exergy in a High-Temperature Heat Pump System Operating with Low GWP Refrigerants

Authors: Adam Y. Sulaiman, Donal F. Cotter, Ming J. Huang, Neil J. Hewitt

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Suitable low global warming potential (GWP) refrigerants that conform to F-gas regulations are required to extend the operational envelope of high-temperature heat pumps (HTHPs) used for industrial waste heat recovery processes. The thermophysical properties and characteristics of these working fluids need to be assessed to provide a comprehensive understanding of operational effectiveness in HTHP applications. This paper presents the results of a theoretical simulation to investigate a range of low-GWP refrigerants and their suitability to supersede refrigerants HFC-245fa and HFC-365mfc. A steady-state thermodynamic model of a single-stage HTHP with an internal heat exchanger (IHX) was developed to assess system cycle characteristics at temperature ranges between 50 to 80 °C heat source and 90 to 150 °C heat sink. A practical approach to maximize the operational efficiency was examined to determine the effects of regulating minimum superheat within the process and subsequent influence on energetic and exergetic efficiencies. A comprehensive map of minimum superheat across the HTHP operating variables were used to assess specific tipping points in performance at 30 and 70 K temperature lifts. Based on initial results, the refrigerants HCFO-1233zd(E) and HFO-1336mzz(Z) were found to be closely aligned matches for refrigerants HFC-245fa and HFC-365mfc. The overall results show effective performance for HCFO-1233zd(E) occurs between 5-7 K minimum superheat, and HFO-1336mzz(Z) between 18-21 K dependant on temperature lift. This work provides a method to optimize refrigerant selection based on operational indicators to maximize overall HTHPs system performance.

Keywords: high-temperature heat pump, minimum superheat, energy & exergy efficiency, low GWP refrigerants

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792 Population Growth of Bracon hebetor Say. under the Influence of Various Lepidopteran Host

Authors: Mohammad Muslim, M. Shafiq Ansari, Fazil Hasan

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Bracon hebetor Say (Hymenoptera: Braconidae) is considered as a highly cosmopolitan ecto-parasitoid of various species of order Lepidoptera. To study the influence of lepidopteran hosts on population growth of B. hebetor, the newly mated gravid females were released on various host and the eggs laid by such females on respective host were counted and a single egg was allow to develop on single host larvae. The experiment was conducted at 27 ± 1°C, 65 ± 5% RH and 14L: 10D hr in Biological Oxygen Demand (BOD) chamber. Upon hatching the tiny larvae of parasitoid pierced the body of insect host, enter into them and consumed the internal body contents of paralyzed host larvae. Present findings showed that B. hebetor took ~36 days to complete its survivorship on Corcyra cephalonica and Galleria mellonella. However, on Spodoptera littoralis the survivorship decreased to 24 days. Nevertheless, development of H. hebetor’s immature was significantly prolonged on S. littoralis and S. litura compared to other insect hosts tested. Female of B. hebetor took longer time to lay eggs on C. cephalonica and G. mellonella than other hosts tested in this study. Longevity of male and female is significantly prolonged on C. cephalonica and G. mellonella compared to others insect hosts tested. Population growth parameters like mx Ro, rm, Tc, and τ was considerably highest on C. cephalonica and lowest on S. littoralis. Based on the demographic studies C. cephalonica and H. armegera were proved to be the most suitable host for the mass rearing of B. hebetor. Nevertheless, results of present investigation could be utilized to improve the mass-breeding program of B. hebetor, so that sufficient number of B. hebetor’s adults could be provided time to time for the effective control of lepidopteran pests of various economically important crops.

Keywords: Bracon hebetor, lepidopteran hosts, demography, biology, development

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791 A Computational Investigation of Knocking Tendency in a Hydrogen-Fueled SI Engine

Authors: Hammam Aljabri, Hong G. Im

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Hydrogen is a promising future fuel to support the transition of the energy sector toward carbon neutrality. The direct utilization of H2 in Internal Combustion Engines (ICEs) is possible, and this technology faces mainly two challenges; high NOx emissions and severe knocking at mid to high loads. In this study, we numerically investigated the potential of H2 combustion in a truck-size engine operated in SI mode. To mitigate the knocking nature of H2 combustion, we have focused on studying the effects of three primary parameters; the compression ratio (CR), the air-fuel ratio, and the spark time. The baseline case was set using a CR of 16.5 and an equivalence ratio of 0.35. In simulations, the auto-ignition tendency was evaluated based on the maximum pressure rise rate and the local pressure fluctuations at the monitoring points set along the wall of the combustion chamber. To mitigate the auto-ignition tendency while enabling a wider range of engine operation, the effect of lowering the compression ratio was assessed. The results indicate that by lowering the compression ratio from 16.5:1 to 12.5:1, an indicated thermal efficiency of 47.5% can be achieved. Aiming to restrain the auto-ignition while maintaining good efficiency, a reduction in the equivalence ratio was examined under different compression ratios. The result indicates that higher compression ratios will require lower equivalence ratios, and due to practical limitations, a lower equivalence ratio of 0.25 was set as the limit. Using a compression ratio of 13.5 combined with an equivalence ratio of 0.3 resulted in an indicated thermal efficiency of 48.6%, that is, at a fixed spark time. It is found that under such lean conditions, the incomplete combustion losses and exhaust losses were high. Thus, advancing the spark time was assessed as a possible solution. The results demonstrated the advantages of advancing the spark time, where an indicated thermal efficiency exceeding 50% was achieved using a compression ratio of 14.5:1 and an equivalence ratio of 0.25.

Keywords: hydrogen, combustion, engine knock, SI engine

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790 Strategic Development of Urban Environmental Management Base on Good Governance - Case study of (Waste Management of Tehran)

Authors: A. Farhad Sadri, B. Ali Farhadi, C. Nasim Shalamzari

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Waste management is a principle of urban and environmental governance. Waste management in Tehran metropolitan requires good strategies for better governance. Using of good urban governance principles together with eight main indexes can be an appropriate base for this aim. One of the reasonable tools in this field is usage of SWOT methods which provides possibility of comparing the opportunities, threats, weaknesses, and strengths by using IFE and EFE matrixes. The results of the above matrixes, respectively 2.533 and 2.403, show that management system of Tehran metropolitan wastes has performed weak regarding to internal factors and has not have good performance regarding using the opportunities and dealing with threats. In this research, prioritizing and describing the real value of each 24 strategies in waste management in Tehran metropolitan have been surveyed considering good governance derived from Quantitative Strategic Planning Management (QSPM) by using Kolomogrof-Smirnoff by 1.549 and significance level of 0.073 in order to define normalization of final values and all of the strategies utilities and Variance Analysis of ANOVA has been calculated for all SWOT strategies. Duncan’s test results regarding four WT, ST, WO, and SO strategies show no significant difference. In addition to mean comparison by Duncan method in this research, LSD (Lowest Significant Difference test) has been used by probability of 5% and finally, 7 strategies and final model of Tehran metropolitan waste management strategy have been defined. Increasing the confidence of people with transparency of budget, developing and improving the legal structure (rule-oriented and law governance, more responsibility about requirements of private sectors, increasing recycling rates and real effective participation of people and NGOs to improve waste management (contribution) and etc, are main available strategies which have been achieved based on good urban governance management principles.

Keywords: waste, strategy, environmental management, urban good governance, SWOT

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789 Ajmer Dargah: Sustaining the Identity of a Religious Precinct

Authors: Vinod Chovvayil Panengal

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The idea of secularism in India has taken a different direction after independence when religion became a reason for a great divide in, otherwise harmonious society. Since then the religious spaces became protected and more sacred and not shared. However, there is a larger threat on beliefs, rituals, and the spirituality of these religions in the form of technology, tourism and globalization. In a way, they weaken the importance of religion from our society over a period of time. The importance of religion to a sense of place has been overlooked or diminished. Religion provides symbolic meaning to places which distinguishes certain physical environments from otherwise similar ones. The rapid transformation of urban spaces, eliminating the territorial differences of sense, spirit and identity have started creating urban centers rooting out this genre of unique urban spaces from our cities. Indian cities, with a strong identity created by rich and colorful overlays of culture through its evolution, have been threatened by this de-territorialization. This paper enquires the relationship of the symbol of the identity and religiosity of a place, through spatial form, rituals and activity, and accommodating the technology and the changing social structure within the bounds of that relationship. The subjects for this enquiry are Sufism and the Sufi city- Ajmer. The internal transformations in the ideologies of Islam and Sufism and the changes in the society surround it triggered the phenomena of de- territorialization. The need for establishing a symbiotic relationship between the spiritual content and the social life, through the manifestation of space, time and activity derived from this concern on abated territory of Sufism inside the city. Redirecting transformation catalyst such as tourism, technology, etc, towards the improvement of physical and social conditions, preservation of the heritage and the expansion of the notional idea of religion over the city will help to re- territorialize city as a Sufi city.

Keywords: sense of place, religion, Islam, identity

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788 Ultra-High Voltage Energization of Electrostatic Precipitators for Coal Fired Boilers

Authors: Mads Kirk Larsen

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Strict air pollution control is today high on the agenda world-wide. By reducing the particular emission, not only the mg/Nm3 will be reduced – also parts of mercury and other hazardous matters attached to the particles will be reduced. Furthermore, it is possible to catch the fine particles (PM2.5). For particulate control, the precipitators are still the preferred choice and much efforts have been done to improve the efficiencies. Many ESP’s have seen electrical upgrading by changing the traditional 1 phase power system into either 3 phase or SMPS (High Frequency) units. However, there exist a 4th type of power supply – the pulse type. This is unfortunately widely unknown, but may be of great benefit to power plants. The FLSmidth type is called COROMAX® and it is a high voltage pulse generator for precipitators using a semiconductor switch operating at medium potential. The generated high voltage pulses have rated amplitude of 80 kV and duration of 75 μs and are superimposed on a variable base voltage of 60 kV rated voltage. Hereby, achieving a peak voltage of 140 kV. COROMAX® has the ability to increase the voltage beyond the natural spark limit inside the precipitator. Voltage levels may often be twice as high after installation of COROMAX®. Hereby also the migration velocity increases and thereby the efficiency. As the collection efficiency is proportional to the voltage peak and mean values, this also increases the collection efficiency of the fine particles where test has shown 80% removal of particles less than 0.07 micron. Another great advantage is the indifference to back-corona. Simultaneously with emission reduction, the power consumption will also be reduced. Another great advantage of the COROMAX® system is that the emission can be improved without the need to change the internal parts or enlarge the ESP. Recently, more than 150 units have been installed in China, where emissions have been reduced to ultra-low levels.

Keywords: eleectrostatic precipitator, high resistivity dust, micropulse energization, particulate removal

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787 Proactive Business Approaches in Human Rights: The Implications of Corporate Social Responsibility

Authors: Fatemeh Jalalvand

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The critical human rights problems such as extreme poverty, hunger, inequalities and gender discrimination need to be addressed by powerful and influential actors in the world. In today’s globalization, corporations have become one of the potent agents in the society. They are capable of generating economic growth, reducing poverty, and increasing the well-being of individuals, thereby contributing to the betterment of a broad spectrum of human rights. However, the discussion on how business can contribute to human rights has primarily focused on not violating them (reactive approach) rather than improving the conditions and solving the problems of human rights (proactive approach). In particular, the role of corporate social responsibility (CSR) in bringing proactivity of business in human rights has gained less attention. This paper develops a conceptual framework to examine the role of different categories of CSR, including discretionary, ethical, legal, instrumental and political CSR in encouraging the proactive contribution of corporations to the betterment of human rights. The five propositions, related to the conceptual framework, outline the relationships between five categories of CSR and proactivity of corporations in human rights. The findings indicate that discretionary CSR with voluntary nature might not be able to motivate any contribution of business in human rights. Moreover, ethical CSR and legal CSR might lead to reactive strategies of business toward human rights. Meanwhile, the economic incentives behind the notion of instrumental CSR could result in partial proactive engagement of corporations in human rights. Finally, the internal motives as profit and power besides the external duties might lead to the highest level of proactivity of corporations in human rights under the context of political CSR. The model developed offers a map for business to adopt proactive human rights strategies more systematically maintaining key profit-drivers like power and profit. In sum, instrumental and political categories of CSR might lead corporations to improve the conditions of human rights proactively.

Keywords: CSR, human rights, proactive approach, reactive approach

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786 Risk Management Practices In The Construction Industry In Malawi

Authors: Taonga Temwani Chibaka

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This qualitative research study was conducted to identify the common risk factors that affect the construction industry in Malawi in the building and infrastructure (civil works) projects. The study then evaluates the possible risk responses that are done to mitigate the various risk factors that were identified. I addition the research also established the barriers to risk management implementation with lastly mapping out as where the identified risk factors fall on which stage of the project and then also map out the knowledge areas that need to be worked on the cases on Malawian construction industry in order to mitigate most of the identified risk factors. The study involved the interviewing the professionals from the construction industry in Malawi where insights and ideas were collected, analysed and interpreted. The key study findings show that risks related to clients group are perceived as most critical followed by the contractor related, consultant related and then external group related factors respectively where preventive measures are the most applied risk response technique where the aim to avoid most of the risk factors from happening. Most of the risk factors identified were internal risks and in managerial category which suggested that risk planning was to be emphasized at pre-contract stage to minimize these risks since a bigger percentage of the risk factors were mapped out at implementation stage. Furthermore, barriers to risk management were identified and the key barriers were lack of awareness; lack of knowledge; lack of formal policies in place; regarded as costly and limited time which resulted in proposing that regulating authorities to purposefully introduce intense training on risk management to make known of this new knowledge area. The study then recommends that organisation should formally implement risk management where policies should be introduced to enforce all parties to undertake this. Risk planning was regarded as paramount and this to be done from pre-contract phase so as to mitigate 80% of the risk factors. Finally, training should be done on all project management knowledge areas.

Keywords: risk management, risk factors, risks, malawi

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785 Solid Phase Micro-Extraction/Gas Chromatography-Mass Spectrometry Study of Volatile Compounds from Strawberry Tree and Autumn Heather Honeys

Authors: Marinos Xagoraris, Elisavet Lazarou, Eleftherios Alissandrakis, Christos S. Pappas, Petros A. Tarantilis

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Strawberry tree (Arbutus unedo L.) and autumn heather (Erica manipuliflora Salisb.) are important beekeeping plants of Greece. Six monofloral honeys (four strawberry tree, two autumn heather) were analyzed by means of Solid Phase Micro-Extraction (SPME, 60 min, 60 oC) followed by Gas Chromatography coupled to Mass Spectrometry (GC-MS) for the purpose of assessing the botanical origin. A Divinylbenzene/Carboxen/Polydimethylsiloxane (DVB/CAR/PDMS) fiber was employed, and benzophenone was used as internal standard. The volatile compounds with higher concentration (μg/ g of honey expressed as benzophenone) from strawberry tree honey samples, were α-isophorone (2.50-8.12); 3,4,5-trimethyl-phenol (0.20-4.62); 2-hydroxy-isophorone (0.06-0.53); 4-oxoisophorone (0.38-0.46); and β-isophorone (0.02-0.43). Regarding heather honey samples, the most abundant compounds were 1-methoxy-4-propyl-benzene (1.22-1.40); p-anisaldehyde (0.97-1.28); p-anisic acid (0.35-0.58); 2-furaldehyde (0.52-0.57); and benzaldehyde (0.41-0.56). Norisoprenoids are potent floral markers for strawberry-tree honey. β-isophorone is found exclusively in the volatile fraction of this type of honey, while also α-isophorone, 4-oxoisophorone and 2-hydroxy-isophorone could be considered as additional marker compounds. The analysis of autumn heather honey revealed that phenolic compounds are the most abundant and p-anisaldehyde; 1-methoxy-4-propyl-benzene; and p-anisic acid could serve as potent marker compounds. In conclusion, marker compounds for the determination of the botanical origin for these honeys could be identified as several norisoprenoids and phenolic components were found exclusively or in higher concentrations compared to common Greek honey varieties.

Keywords: SPME/GC-MS, volatile compounds, heather honey, strawberry tree honey

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784 Living Wall Systems: An Approach for Reducing Energy Consumption in Curtain Wall Façades

Authors: Salma Maher, Ahmed Elseragy, Sally Eldeeb

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Nowadays, Urbanism and climate change lead to the rapid growth in energy consumption and the increase of using air-conditioning for cooling. In a hot climate area, there is a need for a new sustainable alternative that is more convenient for an existing situation. The Building envelope controls the heat transfer between the outside and inside the building. While the building façade is the most critical part, types of façade material play a vital role in influences of the energy demand for heating and cooling due to exposure to direct solar radiation throughout the day. Since the beginning of the twentieth century, the use of curtain walls in office buildings façades started to increase rapidly, which lead to more cooling loads in energy consumption. Integrating the living wall system in urban areas as a sustainable renovation and energy-saving method for the built environment will reduce the energy demand of buildings and will also provide environmental benefits. Also, it will balance the urban ecology and enhance urban life quality. The results show that the living wall systems reduce the internal temperature up to 4.0 °C. This research carries on an analytical study by highlighting the different types of living wall systems and verifying their thermal performance, energy-saving, and life potential on the building. These assessing criteria include the reason for using the Living wall systems in the building façade as well as the effect it has upon the surrounding environment. Finally, the paper ends with concluding the effect of using living wall systems on building. And, it suggests a system as long-lasting, and energy-efficient solution to be applied in curtain wall façades in a hot climate area.

Keywords: living wall systems, energy consumption, curtain walls, energy-saving, sustainability, urban life quality

Procedia PDF Downloads 141
783 Impact of Charging PHEV at Different Penetration Levels on Power System Network

Authors: M. R. Ahmad, I. Musirin, M. M. Othman, N. A. Rahmat

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Plug-in Hybrid-Electric Vehicle (PHEV) has gained immense popularity in recent years. PHEV offers numerous advantages compared to the conventional internal-combustion engine (ICE) vehicle. Millions of PHEVs are estimated to be on the road in the USA by 2020. Uncoordinated PHEV charging is believed to cause severe impacts to the power grid; i.e. feeders, lines and transformers overload and voltage drop. Nevertheless, improper PHEV data model used in such studies may cause the findings of their works is in appropriated. Although smart charging is more attractive to researchers in recent years, its implementation is not yet attainable on the street due to its requirement for physical infrastructure readiness and technology advancement. As the first step, it is finest to study the impact of charging PHEV based on real vehicle travel data from National Household Travel Survey (NHTS) and at present charging rate. Due to the lack of charging station on the street at the moment, charging PHEV at home is the best option and has been considered in this work. This paper proposed a technique that comprehensively presents the impact of charging PHEV on power system networks considering huge numbers of PHEV samples with its traveling data pattern. Vehicles Charging Load Profile (VCLP) is developed and implemented in IEEE 30-bus test system that represents a portion of American Electric Power System (Midwestern US). Normalization technique is used to correspond to real time loads at all buses. Results from the study indicated that charging PHEV using opportunity charging will have significant impacts on power system networks, especially whereas bigger battery capacity (kWh) is used as well as for higher penetration level.

Keywords: plug-in hybrid electric vehicle, transportation electrification, impact of charging PHEV, electricity demand profile, load profile

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782 Argentine Immigrant Policy: A Qualitative Analysis of Changes and Trends from 2016 on

Authors: Romeu Bonk Mesquita

Abstract:

Argentina is the South American number 1 country of destiny to intraregional migration flows. This research aims to shed light on the main trends of the Argentine immigrant policy from 2016 on, when Mauricio Marci was elected President, taking the approval of the current and fairly protective of human rights Ley de Migraciones (2003) as an analytical starting point. Foreign Policy Analysis (FPA) serves as the theoretical background, highlighting decision-making processes and institutional designs that encourage or constraint political and social actors. The analysis goes through domestic and international levels, observing how immigration policy is formulated as a public policy and is simultaneously connected to Mercosur and other international organizations, such as the International Organization for Migration (IOM) and the United Nations High Commissioner for Refugees (UNHCR). Thus, the study revolves around the Direccion Nacional de Migraciones, which is the state agency in charge of executing the country’s immigrant policy, as to comprehend how its internal processes and the connections it has with both domestic and international institutions shape Argentina’s immigrant policy formulation and execution. Also, it aims to locate the migration agenda within the country’s contemporary social and political context. The methodology is qualitative, case-based and oriented by process-tracing techniques. Empirical evidence gathered includes official documents and data, media coverage and interviews to key-informants. Recent events, such as the Decreto de Necesidad y Urgencia 70/2017 issued by President Macri, and the return of discursive association between migration and criminality, indicate a trend of nationalization and securitization of the immigration policy in contemporary Argentina.

Keywords: Argentine foreign policy, human rights, immigrant policy, Mercosur

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781 Experimental and Modal Determination of the State-Space Model Parameters of a Uni-Axial Shaker System for Virtual Vibration Testing

Authors: Jonathan Martino, Kristof Harri

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In some cases, the increase in computing resources makes simulation methods more affordable. The increase in processing speed also allows real time analysis or even more rapid tests analysis offering a real tool for test prediction and design process optimization. Vibration tests are no exception to this trend. The so called ‘Virtual Vibration Testing’ offers solution among others to study the influence of specific loads, to better anticipate the boundary conditions between the exciter and the structure under test, to study the influence of small changes in the structure under test, etc. This article will first present a virtual vibration test modeling with a main focus on the shaker model and will afterwards present the experimental parameters determination. The classical way of modeling a shaker is to consider the shaker as a simple mechanical structure augmented by an electrical circuit that makes the shaker move. The shaker is modeled as a two or three degrees of freedom lumped parameters model while the electrical circuit takes the coil impedance and the dynamic back-electromagnetic force into account. The establishment of the equations of this model, describing the dynamics of the shaker, is presented in this article and is strongly related to the internal physical quantities of the shaker. Those quantities will be reduced into global parameters which will be estimated through experiments. Different experiments will be carried out in order to design an easy and practical method for the identification of the shaker parameters leading to a fully functional shaker model. An experimental modal analysis will also be carried out to extract the modal parameters of the shaker and to combine them with the electrical measurements. Finally, this article will conclude with an experimental validation of the model.

Keywords: lumped parameters model, shaker modeling, shaker parameters, state-space, virtual vibration

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780 Modeling of Glycine Transporters in Mammalian Using the Probability Approach

Authors: K. S. Zaytsev, Y. R. Nartsissov

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Glycine is one of the key inhibitory neurotransmitters in Central nervous system (CNS) meanwhile glycinergic transmission is highly dependable on its appropriate reuptake from synaptic cleft. Glycine transporters (GlyT) of types 1 and 2 are the enzymes providing glycine transport back to neuronal and glial cells along with Na⁺ and Cl⁻ co-transport. The distribution and stoichiometry of GlyT1 and GlyT2 differ in details, and GlyT2 is more interesting for the research as it reuptakes glycine to neuron cells, whereas GlyT1 is located in glial cells. In the process of GlyT2 activity, the translocation of the amino acid is accompanied with binding of both one chloride and three sodium ions consequently (two sodium ions for GlyT1). In the present study, we developed a computer simulator of GlyT2 and GlyT1 activity based on known experimental data for quantitative estimation of membrane glycine transport. The trait of a single protein functioning was described using the probability approach where each enzyme state was considered separately. Created scheme of transporter functioning realized as a consequence of elemental steps allowed to take into account each event of substrate association and dissociation. Computer experiments using up-to-date kinetic parameters allowed receiving the number of translocated glycine molecules, Na⁺ and Cl⁻ ions per time period. Flexibility of developed software makes it possible to evaluate glycine reuptake pattern in time under different internal characteristics of enzyme conformational transitions. We investigated the behavior of the system in a wide range of equilibrium constant (from 0.2 to 100), which is not determined experimentally. The significant influence of equilibrium constant in the range from 0.2 to 10 on the glycine transfer process is shown. The environmental conditions such as ion and glycine concentrations are decisive if the values of the constant are outside the specified range.

Keywords: glycine, inhibitory neurotransmitters, probability approach, single protein functioning

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779 Investigating the Relative Priority of the Factors Affecting Customer Satisfaction in Gaining the Competitive Advantage in Pars-Khazar Company

Authors: Samaneh Pouyanfar, Michael Oliff

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The industry of home appliances may beone of theindustries which has the highest competition, and actually what can guarantee the survival of this industry is discovering the superior services. A trend to provide quality products and services plays an important role in this industry because discovering the services is counted as a vital affair for Manufacturing Organizations’ survival and profitability. Given the importance of the topic, this paper attempts to investigate the relative priority of the factors influencing the customer satisfaction in gaining the competitive advantage in Pars-Khazar Company. In sum, 96 executives of Pars-Khazar Company where investigated in a census. For this purpose, after reviewing the research literature and performing deep interviews between pundits and experts active in the industry, the research questionnaire was made based on variables affecting customer satisfaction and components determining business competitive advantage. Determining the content validity took place by judgement of the experts. The reliability of each structure was measured based on Cronbach’s alpha coefficient. Since the value of Cronbach's alpha was higher than 0.7 for each structure, internal consistency of statements was high and the reliability of the questionnaire was acceptable. The data analysis was also done with Kulmgrf-asmyrnf test and Friedman test using SPSS software. The results showed that in dimension of factors affecting customer satisfaction, the History of trade name (brand), Familiarity with the product brand, Brand reputation and Safety have the highest value of priority respectively, and the variable of firm growth has the highest value of priority among the components determining the performance of competitive advantage.

Keywords: customer satisfaction, competitive advantage, brand history, safety, growth

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778 Developing a DNN Model for the Production of Biogas From a Hybrid BO-TPE System in an Anaerobic Wastewater Treatment Plant

Authors: Hadjer Sadoune, Liza Lamini, Scherazade Krim, Amel Djouadi, Rachida Rihani

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Deep neural networks are highly regarded for their accuracy in predicting intricate fermentation processes. Their ability to learn from a large amount of datasets through artificial intelligence makes them particularly effective models. The primary obstacle in improving the performance of these models is to carefully choose the suitable hyperparameters, including the neural network architecture (number of hidden layers and hidden units), activation function, optimizer, learning rate, and other relevant factors. This study predicts biogas production from real wastewater treatment plant data using a sophisticated approach: hybrid Bayesian optimization with a tree-structured Parzen estimator (BO-TPE) for an optimised deep neural network (DNN) model. The plant utilizes an Upflow Anaerobic Sludge Blanket (UASB) digester that treats industrial wastewater from soft drinks and breweries. The digester has a working volume of 1574 m3 and a total volume of 1914 m3. Its internal diameter and height were 19 and 7.14 m, respectively. The data preprocessing was conducted with meticulous attention to preserving data quality while avoiding data reduction. Three normalization techniques were applied to the pre-processed data (MinMaxScaler, RobustScaler and StandardScaler) and compared with the Non-Normalized data. The RobustScaler approach has strong predictive ability for estimating the volume of biogas produced. The highest predicted biogas volume was 2236.105 Nm³/d, with coefficient of determination (R2), mean absolute error (MAE), and root mean square error (RMSE) values of 0.712, 164.610, and 223.429, respectively.

Keywords: anaerobic digestion, biogas production, deep neural network, hybrid bo-tpe, hyperparameters tuning

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777 Prevalence of Different Poultry Parasitoses in Farms Modern in the North of Ivory Coast

Authors: Coulibaly Fatoumata, Gragnon Biego, Aka N. David, Mbari K. Benjamin, Soro Y. René, Ndiaye Jean-louis

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Poultry is nowadays one of the most consumed sources of protein, and its livestock represents one of the few opportunities for savings, investment and protection against risk. It provides income for the most vulnerable sections of society, in particular, women (70%) and children who mainly practice this breeding. A study was conducted in the commune of Korhogo at the level of 52 poultry farms, the objective of which was to know the epidemiological situation of parasitism external and internal poultry in order to contribute to the improvement of the health status of modern poultry farms in the said commune. The method described by OIE (2005), consisting of using the standard formula (n = δ2*p*(1-p) *c /i2), made it possible to calculate the size of the sample. Then, samples of droppings and ectoparasites were taken from the affected farms. After analysis and identification, two (2) species of mallophagous lice, including Menopon gallinae (50%) and Menacanthus stramineus (33%) and a species of bug Cimex lectularius (17%) were highlighted. The laying hens were more infested than broilers. Regarding gastrointestinal parasites, different species (six) have been identified: Trichostrongylus tenuis (17%), Syngamus trachea (19%), Heterakis sp (10%), Ascaridia sp (17%), Raillietina sp (8%) and Eimeria sp (29%). In addition, coccidiosis (Eimeria sp) proved to be the dominant pathology representing 67% of pathologies in broiler farms and 33% in poultry farms. The presence of these parasitoses in these modern farms constitutes a constraint major contribution to productivity and their development In view of all these difficulties, proposals have been made in order to participate in the establishment of a good prophylaxis program (health and medical). In addition, the Ivorian government, with the support of veterinarians, must interfere more in the organization of the health monitoring of traditional chickens and poultry in general through supervision and training in order to preserve public health ( animal, human and environmental health).

Keywords: gastrointestinal parasites, ectoparasites, pathologies, poultry, korhogo.

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776 The Role of the Federal Supreme Court in Preventing the Exercise of the Right to Self-Determination

Authors: Shaho Ghafur Ahmed

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The right to self-determination of peoples is a fundamental human right recognized by the principles of international law. It could be embodied in the internal level in the form of federalism. Most federal constitutions prevented the secession of constituent entities, while some remained silent, as the case of Iraq, and rare instances of them recognize it. But, after the failure of federalism, these entities seek to separate whenever the opportunity arises. In several cases, they have resort to peaceful methods in some others they resort to force. The constitutional Supreme Court, which guaranty the unity and integrity of the State, often prevent these attempts. After not a commitment of federalism in Iraq, which has been founded since 2004, the Kurdistan region, as the only federated entity, has conducted a unilateral referendum on 25 September 2017 for its independence. The Iraqi government refused it. The Iraqi Federal Supreme Court, through interpreting the constitutional provisions, decided that this referendum and it’s purposes, which was the independence of the region, was unconstitutional. Subsequently, the Iraqi government used forces and blockaded the region so as to force it to turn off this process. So, in this paper, the right to self-determination of the peoples in federated entities and its obstacles will be discussed through the comparative legal basis and analyzing the decisions of the Federal Constitutional Courts. We will compare the role that the Supreme Court of Canada played regarding the referendum that operated in Quebec in 1995, in which it refused only the unilaterally attempts for the independence of this province. While, in the case of the Kurdistan region, the Iraqi Federal Supreme Court has definitively refused this right. No measures were taken by this Court to protect the region from the Iraqi government reactions. This decision led to the questioning of the neutrality of this Court. So, from the point of view of the Kurdistan region, this Court became a political instrument to prevent it to be independent in the international community, in the absence of a clear constitutional provision, through an abstract and an incomplete interpretation of federal constitutional provisions.

Keywords: right of self-determination, federal supreme court, supremacy of federal constitution

Procedia PDF Downloads 169
775 Statistical Process Control in Manufacturing, a Case Study on an Iranian Automobile Company

Authors: M. E. Khiav, D. J. Borah, H. T. S. Santos, V. T. Faria

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For automobile companies, it has become very important to ensure sound quality in manufacturing and assembling in order to prevent occurrence of defects and to reduce the amount of parts replacements to be done in the service centers during the warranty period. Statistical Process Control (SPC) is widely used as the tool to analyze the quality of such processes and plays a significant role in the improvement of the processes by identifying the patterns and the location of the defects. In this paper, a case study has been conducted on an Iranian automobile company. This paper performs a quality analysis of a particular component called “Internal Bearing for the Back Wheel” of a particular car model, manufactured by the company, based on the 10 million data received from its service centers located all over the country. By creating control charts including X bar–S charts and EWMA charts, it has been observed after the year 2009, the specific component underwent frequent failures and there has been a sharp dip in the average distance covered by the cars till the specific component requires replacement/maintenance. Correlation analysis was performed to find out the reasons that might have affected the quality of the specific component in all the cars produced by the company after the year 2009. Apart from manufacturing issues, some political and environmental factors have been identified to have a potential impact on the quality of the component. A maiden attempt has been made to analyze the quality issues within an Iranian automobile manufacturer; such issues often get neglected in developing countries. The paper also discusses the possibility of political scenario of Iran and the country’s environmental conditions affecting the quality of the end products, which not only strengthens the extant literature but also provides a new direction for future research.

Keywords: capability analysis, car manufacturing, statistical process control, quality control, quality tools

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774 Characterization of White Spot Lesion Using Focused Ion Beam - Scanning Electron Microscopy

Authors: Malihe Moeinin, Robert Hill, Ferranti Wong

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Background: A white spot lesion (WSL) is defined as subsurface enamel porosity from carious demineralisation on the smooth surfaces of the tooth. It appears as a milky white opacity. Lesions shown an apparently intact surface layer, followed underneath by the more porous lesion body. The small pores within the body of the lesion act as diffusion pathway for both acids and minerals, so allowing the demineralisation of enamel to occur at the advancing front of the lesion. Objectives: The objective is to mapthe porosity and its size on WSL with Focused Ion Bean- Scanning Electron Microscopy (FIB-SEM) Method: The basic method used for FIB-SEM consisted of depositing a one micron thick layer of platinum over 25μmx 25μm of the interest region of enamel. Then, making a rough cut (25μmx 5μmx 20μm) with 3nA current and 30Kv was applied with the help of drift suppression (DS), using a standard “cross-sectional” cutting pattern, which ended at the front of the deposited platinum layer. Two adjacent areas (25μmx 5μmx 20μm) on the both sides of the platinum layer were milled under the same conditions. Subsequent, cleaning cross-sections were applied to polish the sub-surface edge of interest running perpendicular to the surface. The "slice and view" was carried out overnight for milling almost 700 slices with 2Kv and 4nA and taking backscattered (BS) images. Then, images were imported into imageJ and analysed. Results: The prism structure is clearly apparent on FIB-SEM slices of WSL with the dissolution of prism boundaries as well as internal porosity within the prism itself. Porosity scales roughly 100-400nm, which is comparable to the light wavelength (500nm). Conclusion: FIB-SEM is useful to characterize the porosity of WSL and it clearly shows the difference between WSL and normal enamel.

Keywords: white spot lesion, FIB-SEM, enamel porosity, porosity

Procedia PDF Downloads 94