Search results for: tuning phenomenon
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2404

Search results for: tuning phenomenon

964 The Impact of Vertical Velocity Parameter Conditions and Its Relationship with Weather Parameters in the Hail Event

Authors: Nadine Ayasha

Abstract:

Hail happened in Sukabumi (August 23, 2020), Sekadau (August 22, 2020), and Bogor (September 23, 2020), where this extreme weather phenomenon occurred in the dry season. This study uses the ERA5 reanalysis model data, it aims to examine the vertical velocity impact on the hail occurrence in the dry season, as well as its relation to other weather parameters such as relative humidity, streamline, and wind velocity. Moreover, HCAI product satellite data is used as supporting data for the convective cloud development analysis. Based on the results of graphs, contours, and Hovmoller vertical cut from ERA5 modeling, the vertical velocity values in the 925 Mb-300 Mb layer in Sukabumi, Sekadau, and Bogor before the hail event ranged between -1.2-(-0.2), -1.5-(-0.2), -1-0 Pa/s. A negative value indicates that there is an upward motion from the air mass that trigger the convective cloud growth, which produces hail. It is evidenced by the presence of Cumulonimbus cloud on HCAI product when the hail falls. Therefore, the vertical velocity has significant effect on the hail event. In addition, the relative humidity in the 850-700 Mb layer is quite wet, which ranges from 80-90%. Meanwhile, the streamline and wind velocity in the three regions show the convergence with slowing wind velocity ranging from 2-4 knots. These results show that the upward motion of the vertical velocity is enough to form the wet atmospheric humidity and form a convergence for the growth of the convective cloud, which produce hail in the dry season.

Keywords: hail, extreme weather, vertical velocity, relative humidity, streamline

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963 New Findings on the Plasma Electrolytic Oxidation (PEO) of Aluminium

Authors: J. Martin, A. Nominé, T. Czerwiec, G. Henrion, T. Belmonte

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The plasma electrolytic oxidation (PEO) is a particular electrochemical process to produce protective oxide ceramic coatings on light-weight metals (Al, Mg, Ti). When applied to aluminum alloys, the resulting PEO coating exhibit improved wear and corrosion resistance because thick, hard, compact and adherent crystalline alumina layers can be achieved. Several investigations have been carried out to improve the efficiency of the PEO process and one particular way consists in tuning the suitable electrical regime. Despite the considerable interest in this process, there is still no clear understanding of the underlying discharge mechanisms that make possible metal oxidation up to hundreds of µm through the ceramic layer. A key parameter that governs the PEO process is the numerous short-lived micro-discharges (micro-plasma in liquid) that occur continuously over the processed surface when the high applied voltage exceeds the critical dielectric breakdown value of the growing ceramic layer. By using a bipolar pulsed current to supply the electrodes, we previously observed that micro-discharges are delayed with respect to the rising edge of the anodic current. Nevertheless, explanation of the origin of such phenomena is still not clear and needs more systematic investigations. The aim of the present communication is to identify the relationship that exists between this delay and the mechanisms responsible of the oxide growth. For this purpose, the delay of micro-discharges ignition is investigated as the function of various electrical parameters such as the current density (J), the current pulse frequency (F) and the anodic to cathodic charge quantity ratio (R = Qp/Qn) delivered to the electrodes. The PEO process was conducted on Al2214 aluminum alloy substrates in a solution containing potassium hydroxide [KOH] and sodium silicate diluted in deionized water. The light emitted from micro-discharges was detected by a photomultiplier and the micro-discharge parameters (number, size, life-time) were measured during the process by means of ultra-fast video imaging (125 kfr./s). SEM observations and roughness measurements were performed to characterize the morphology of the elaborated oxide coatings while XRD was carried out to evaluate the amount of corundum -Al203 phase. Results show that whatever the applied current waveform, the delay of micro-discharge appearance increases as the process goes on. Moreover, the delay is shorter when the current density J (A/dm2), the current pulse frequency F (Hz) and the ratio of charge quantity R are high. It also appears that shorter delays are associated to stronger micro-discharges (localized, long and large micro-discharges) which have a detrimental effect on the elaborated oxide layers (thin and porous). On the basis of the results, a model for the growth of the PEO oxide layers will be presented and discussed. Experimental results support that a mechanism of electrical charge accumulation at the oxide surface / electrolyte interface takes place until the dielectric breakdown occurs and thus until micro-discharges appear.

Keywords: aluminium, micro-discharges, oxidation mechanisms, plasma electrolytic oxidation

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962 A Study of the British Security Disembedding Mechanism from a Comparative Political Perspective: Centering on the Bosnia War and the Russian-Ukrainian War

Authors: Yuhong Li, Luyu Mao

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Globalization has led to an increasingly interconnected international community and transmitted risks to every corner of the world through the chain of globalization. Security risks arising from international conflicts seem inescapable. Some countries have begun to build their capacity to deal with the globalization of security risks. They establish disembedding security mechanisms that transcend spatial or temporal boundaries and promote security cooperation with countries or regions that are not geographically close. This paper proposes four hypotheses of the phenomenon of "risks and security disembedding" in the post-Cold War international society and uses them to explain The United Kingdom’s behavior in the Bosnian War and the Russo-Ukrainian War. In the Bosnian War, confident in its own security and focused on maintaining European stability, The UK has therefore chosen to be cautious in its use of force in international frameworks such as the EU and to maintain a very limited intervention in Bosnia and Herzegovina's affairs. In contrast, the failure of the EU and NATO’s security mechanism in the Russo-Ukrainian war heightened Britain's anxiety, and the volatile international situation led it to show a strong tendency towards security disembedding, choosing to conclude security communities with extra-territorial states. Analysis suggests that security mechanisms are also the starting point of conflict and that countries will rely more on disembedding mechanisms to counteract the global security risks. The current mechanism of security disembedding occurs as a result of the global proliferation of security perceptions as a symbolic token and the recognition of an expert system of security mechanisms formed by states with similar security perceptions.

Keywords: disembedding mechanism, bosnia war, the russian-ukrainian war, british security strategy

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961 A Preliminary Literature Review of Digital Transformation Case Studies

Authors: Vesna Bosilj Vukšić, Lucija Ivančić, Dalia Suša Vugec

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While struggling to succeed in today’s complex market environment and provide better customer experience and services, enterprises encompass digital transformation as a means for reaching competitiveness and foster value creation. A digital transformation process consists of information technology implementation projects, as well as organizational factors such as top management support, digital transformation strategy, and organizational changes. However, to the best of our knowledge, there is little evidence about digital transformation endeavors in organizations and how they perceive it – is it only about digital technologies adoption or a true organizational shift is needed? In order to address this issue and as the first step in our research project, a literature review is conducted. The analysis included case study papers from Scopus and Web of Science databases. The following attributes are considered for classification and analysis of papers: time component; country of case origin; case industry and; digital transformation concept comprehension, i.e. focus. Research showed that organizations – public, as well as private ones, are aware of change necessity and employ digital transformation projects. Also, the changes concerning digital transformation affect both manufacturing and service-based industries. Furthermore, we discovered that organizations understand that besides technologies implementation, organizational changes must also be adopted. However, with only 29 relevant papers identified, research positioned digital transformation as an unexplored and emerging phenomenon in information systems research. The scarcity of evidence-based papers calls for further examination of this topic on cases from practice.

Keywords: digital strategy, digital technologies, digital transformation, literature review

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960 On the Causes of Boko Haram Terrorism: Socio-Economic versus Religious Injunctions

Authors: Sogo Angel Olofinbiyi

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There have been widespread assumptions across the globe that the root cause of Boko Haram terrorism in Nigeria is religious rather than socio-economic. An investigation into this dichotomy allowed this study to fully demonstrate that the root cause of Boko Haram’s terrorist actions emanates from the non-fulfillment of socio-economic goals that are prompted by the violation of fundamental human rights, corruption, poverty, unconstitutional and undemocratic practices in the northern part of the Nigerian state. To achieve its aim of establishing the root cause of the terrorism crisis in the latter country, the study critically appraised the socio-economic context of the insurgency by adopting one-on-one in-depth interviews involving forty (40) participants to interrogate the phenomenon. Empirical evidence from the study demonstrated that the evolution of Boko Haram terrorism was a response to socio-economic phlebotomy, political and moral putrescence, and the dehumanization of people that stem from a combination of decades of mismanagement and pervasive corruption by various Nigerian leaders. The study concludes that, as long as the endemic socio-economic problems caused by global capitalism vis-a-vis unequal hegemonic power exchange as expressed in socio-political, ethno-religious and cultural forms persist in the Nigerian society, the terrorism insurgency will recur and remain an inevitable enterprise and indeed a normal social reaction to every undesirable state of affairs. Based on the findings, the study urges the need for the amelioration of the conditions of the vast majority of the Nigerian populace by making socio-economic facilities available to them through the political state.

Keywords: Boko Haram Terrorism, insurgency, socio-economic, religious injunctions

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959 The Impact of Bitcoin and Cryptocurrency on the Development of Community

Authors: Felib Ayman Shawky Salem

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Nowadays crypto currency has become a global phenomenon known to most people. People using this alternative digital money to do a transaction in many ways (e.g. Used for online shopping, wealth management, and fundraising). However, this digital asset also widely used in criminal activities since its use decentralized control as opposed to centralized electronic money and central banking systems and this makes a user, who used this currency invisible. The high-value exchange of these digital currencies also has been a target to criminal activities. The crypto currency crimes have become a challenge for the law enforcement to analyze and to proof the evidence as criminal devices. In this paper, our focus is more on bitcoin crypto currency and the possible artifacts that can be obtained from the different type of digital wallet, which is software and browser-based application. The process memory and physical hard disk are examined with the aims of identifying and recovering potential digital evidence. The stage of data acquisition divided by three states which are the initial creation of the wallet, transaction that consists transfer and receiving a coin and the last state is after the wallet is being deleted. Findings from this study suggest that both data from software and browser type of wallet process memory is a valuable source of evidence, and many of the artifacts found in process memory are also available from the application and wallet files on the client computer storage.

Keywords: cryptocurrency, bitcoin, payment methods, blockchain, appropriation, online retailers, TOE framework, disappropriation, non-appropriationBitCoin, financial protection, crypto currency, money laundering cryptocurrency, digital wallet, digital forensics

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958 Empirical Decomposition of Time Series of Power Consumption

Authors: Noura Al Akkari, Aurélie Foucquier, Sylvain Lespinats

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Load monitoring is a management process for energy consumption towards energy savings and energy efficiency. Non Intrusive Load Monitoring (NILM) is one method of load monitoring used for disaggregation purposes. NILM is a technique for identifying individual appliances based on the analysis of the whole residence data retrieved from the main power meter of the house. Our NILM framework starts with data acquisition, followed by data preprocessing, then event detection, feature extraction, then general appliance modeling and identification at the final stage. The event detection stage is a core component of NILM process since event detection techniques lead to the extraction of appliance features. Appliance features are required for the accurate identification of the household devices. In this research work, we aim at developing a new event detection methodology with accurate load disaggregation to extract appliance features. Time-domain features extracted are used for tuning general appliance models for appliance identification and classification steps. We use unsupervised algorithms such as Dynamic Time Warping (DTW). The proposed method relies on detecting areas of operation of each residential appliance based on the power demand. Then, detecting the time at which each selected appliance changes its states. In order to fit with practical existing smart meters capabilities, we work on low sampling data with a frequency of (1/60) Hz. The data is simulated on Load Profile Generator software (LPG), which was not previously taken into consideration for NILM purposes in the literature. LPG is a numerical software that uses behaviour simulation of people inside the house to generate residential energy consumption data. The proposed event detection method targets low consumption loads that are difficult to detect. Also, it facilitates the extraction of specific features used for general appliance modeling. In addition to this, the identification process includes unsupervised techniques such as DTW. To our best knowledge, there exist few unsupervised techniques employed with low sampling data in comparison to the many supervised techniques used for such cases. We extract a power interval at which falls the operation of the selected appliance along with a time vector for the values delimiting the state transitions of the appliance. After this, appliance signatures are formed from extracted power, geometrical and statistical features. Afterwards, those formed signatures are used to tune general model types for appliances identification using unsupervised algorithms. This method is evaluated using both simulated data on LPG and real-time Reference Energy Disaggregation Dataset (REDD). For that, we compute performance metrics using confusion matrix based metrics, considering accuracy, precision, recall and error-rate. The performance analysis of our methodology is then compared with other detection techniques previously used in the literature review, such as detection techniques based on statistical variations and abrupt changes (Variance Sliding Window and Cumulative Sum).

Keywords: general appliance model, non intrusive load monitoring, events detection, unsupervised techniques;

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957 Crystallized Colored Towels Obtained by Special Coloration of Yarns

Authors: Hasan Eskin, Gizem Özmen, A. Nazmi Çeler

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When we examine the home textile development process, it follows a parallel line with the other textile products especially in the garment fabrics in terms of raw materials, production technologies and pattern characteristics. As a result, the expectations of people regarding textile, comfort, pattern (texture) and color properties are increasing. One of the places where comfort is most sought after is bath, pool, sea and baths. In addition to the material and technique that make up the physical structure in woven fabrics, color has an impressive importance with its strong effects. Color is the most prominent element in the fabric, and the color and texture are visually reinforcing. Evaluation of color in fabric is a personal phenomenon. Factors that determine color determination in fabric are the amount of color used, color ratio and its relationship with other colors. In this project; Considering the effect of color dimensions on human, we are talking about the crystallized colored towel that we developed in terms of comfort and texture properties. The basis of the effect created in the towel; It is formed by bending the yarn from its own special blend and the harmonious appearance of the natural crystallized rainbow colors with the pattern effect it determines on the warp yarns by using the weft yarns in the weaving. In addition, by using different weaving techniques and colors, alternatives can be created and personalized patterns can be created. One side of the towel determines the properties related to color, while the pile part determines the comfort characteristics with its soft touch and water absorbency.

Keywords: color effect, comfort, towel, weaving technique

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956 Textual Analysis of Media Coverage on Women’s Employment during Covid-19 Recovery: Personal Choice versus Systemic Insufficiencies

Authors: Rania Al Namara

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During the Covid-19 pandemic, women disproportionately left the workforce compared to men, and many remained outside of the labor market during the Covid-19 recovery period—a phenomenon referred to as the “she-recession” or “shecession.” While the number of women returning to work has increased, long-standing systemic inequalities interfere with women's equal participation in the workforce. Previous research on media framing has explored the importance of news coverage of women’s issues in print and magazines to shaping the public’s views on an issue and the national response. This study adopts textual analysis to examine how 50 news stories published on CNN and CBS in March 2023 frame women’s employment challenges as a matter of choice or as a matter of insufficient systems and analyzes the narratives portrayed to understand how this discourse affects national policies regarding women’s equality in the workforce. Findings suggest that media coverage centers on four themes: unequal wages at work, work-life integration, experiences of minority women, and the struggle to acquire leadership positions. Media coverage gives space to women to tell personal stories about facing these four societal challenges. However, little coverage is devoted to the political figures and institutions that either reinforce gender inequalities or advance women’s rights in these areas. These findings highlight the need for media stories that discuss policies and reforms that broaden the choices available to women in the first place.

Keywords: Covid-19 recovery, media coverage, shecession, women’s employment

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955 Internal Displacement in Iraq due to ISIS Occupation and Its Effects on Human Security and Coexistence

Authors: Feisal Khudher Mahmood, Abdul Samad Rahman Sultan

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Iraq had been a diverse society with races, cultures and religions that peacefully coexistence. The phenomenon of internal displacement occurred after April 2003, because of political instability as will as the deterioration of the political and security situation as a result of United States of America occupation. Biggest internal displacement have occurred (and keep happening) since 10th of June 2014 due to rise of Islamic State of Iraq and Syria (ISIS) and it’s occupation of one third of country territories. This crisis effected directly 3,275,000 people and reflected negatively on the social fabric of Iraq community and led to waves of sectorial violence that swept the country. Internal displaced communities are vulnerable, especially under non functional and weak government, that led to lose of essential human rights and dignity. Using Geographic Information System (GIS) and Geospatial Techniques, two types of internal displacement have been found; voluntary and forced. Both types of displacement are highly influenced by location, race and religion. The main challenge for Iraqi government and NGOs will be after defeating ISIS. Helping the displaced to resettle within their community and to re-establish the coexistence. By spatial-statical analysis hot spots of future conflicts among displaced community have been highlighted. This will help the government to tackle future conflicts before they occur. Also, it will be the base for social conflict early warning system.

Keywords: internal displacement, Iraq, ISIS, human security, human rights, GIS, spatial-statical analysis

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954 The Influence of Brands in E-Sports Spectators

Authors: Rene Kasper, Hyago Ribeiro, Marcelo Curth

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Electronic sports, or just e-sports, boast an exponential growth in the interest of the public and large investors. The e-sports teams are equal to classic sports teams, like football, since in their structure they have, besides the athletes, administrators, coaches and even doctors. The concept of team games arises with a very strong social interaction, as it is perceived that users interact with real peers rather than competing with intelligent software. In this sense, electronic games are established as a sociocultural phenomenon and as multidimensional media. Thus, the research aims to identify the profile of users and the importance of brands in the Brazilian electronic sports scene, as well as the relationship of consumers (called fans) with the products and services that occupy the media spaces of the transmissions of sports championships. The research used descriptive quantitative methodology, applied in different e-sports communities, with 160 respondents. The data collection instrument was a survey containing seven questions, which addressed the profile of the participants and their perception on the proposed theme in research. Regarding the profile, the age ranged from 17 to 31 years, of which 93.3% were male and 6.7% female. It was found that 93.3% of the participants had contact with the Brazilian electronic sports scene for at least 2 years, of which 26.7% played between 6 and 12 hours a week and 46.7% played more than 12 hours a week. In addition, it was noticed that income was not a deciding factor to enjoy electronic sports games, because the percentage distribution of participants ranged from 1 to 3 minimum wages (33.3%) and greater than 6 salaries (46.7 %). Regarding the brands, 85.6% emphasized that brands should support the scenario through sponsorship and publicity and 28.6% are attracted to consume brands that advertise in e-sports championships.

Keywords: brands, consumer behavior, e-sports, virtual games

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953 Family Depression and Its Relationship with Disability

Authors: Humara Bano, Nyla Anjum

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Disability in any form has great impact not only for the person facing it but also for its family members too. This effect may be so severe that may lead to mal adjustment of any member of the family in society as well. This impact has also been multiplied due to negative attitudes of the society, unawareness about the needs of special needs and no legislation for the parents of children with special needs. As a result not only the separations among the parents have been reported but also the normal siblings in the home are also badly affected in their daily lives. The situation is more challenging when more than one child with disability is present in the family. The main objectives of this paper are to unfold the relationship of variety of disabilities (hearing, visual or physical impairment, mental retardation, speech impairment) in i) developing depression in home setting, ii) social exclusion, iii) anxiety and aggression and iv) development of insecure feelings among family members of the persons with disabilities, as well as, v) to identify coping strategies to manage the special needs by family members too. To reach on conclusion about fifty families (having any sort of disability in their homes) have been interviewed on basis of convenient sampling. Correlation, ANOVA and different analysis have been used to identify the relationship of disability in developing depression among family members in line of above mentioned problems. Results revealed that depression due to disability among families is a common phenomenon and adversely have affected their lives in daily routines as well as in following their life achievements. Coping with the situation and recommending various remedies by parents is the positive reflection of this study too that can help to families in managing their mental health.

Keywords: depression, anxiety and aggression, social exclusion, parents of children with special needs

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952 Representation of Master–Disciple Relationship in Rumi’s Poems: Spirituality Vis-A-Vis Collective Consciousness

Authors: Nodi Islam

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This paper critically reads Rumi’s poems in The Masnavi (Book One) and the philosophy of master-disciple relationship, as reflected as a medium to attain the higher consciousness in the poems which is considered as spiritual by the Sufi practitioners. This paper further applies the concept of collective consciousness introduced by Durkheim, which stands for a set of beliefs, ideas, moral attitudes that operate as a unifying force in a certain society, in reading Rumi’s poems. According to Sufi philosophy, in order to reach to the beloved who is the Higher Being, a lover has to be a disciple of a master and dedicate himself completely even if it means to give up the earthly desires. When the process is completed, he achieves the divinity which is the utmost happiness to be one with the beloved. As this process is considered spiritual by the Sufi practitioners, this paper suggests that, apart from being spiritual, this is a reflection of collective consciousness also. This process plays a part to construct the collectivity as a means to create masters and disciples. Collective consciousness operates in this particular belief system of Sufis who tend to follow this phenomenon as a rule of obedience and accepts the rule because this is how their particular community proceeds on. This paper offers a view of Rumi’s poems which reflect such relationship and tends to offer a general discussion on the hegemonic approach of the Sufi society especially of the Mevlevi order. Finally, this paper offers a constructive representation of Mevlevi society based upon the idea of spirituality which could be an outcome of psychological and social issues and practices.

Keywords: collective consciousness, divinity, master-disciple relationship, Mevlevi order

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951 Role of International Organizations towards Good Governance: Recent Trends

Authors: E. Prema Shyam

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The role of international organizations has contributed in various ways for the good governance in the world at large. Since the beginning of the 1990s international organizations, particularly those active in the areas of human rights, trade and economic etc., have embraced a 'good governance'. It is also pertinent to mention that the application of the concept of good governance to international organizations themselves and not exclusively to national or regional polities is a more recent phenomenon. Especially since the second half of the 1990s, a number of international organizations have carried out major governance reforms, assuming that their calls for governments to heed higher standards of good governance will be all the more credible provided that they develop a good governance standard for themselves. In addition to this number of organizations such as the United Nations (UN), Organisation for Economic Co-operation and Development (OECD), European Union (EU), International Committee of the Red Cross and World Trade Organization (WTO). OECD has been specifically mobilized to fight corruption. The World Bank was the first international organization to address the issue of good governance when it attributed the African development crisis to a crisis of governance in a 1989 report. International organizations are often denounced for their lack of transparency and democracy. However, in the last few years, a number of them have pushed through impressive reforms aimed at enhancing good governance standards within their own organizations, especially in the light of their long-standing secrecy. This is a remnant of the traditional conception of international organizations, which renders them merely answerable to their Members. International organizations have already gone quite some way in the areas of good management and opening up to the public. However, as far as participatory governance is concerned, lot to be done for the larger interest of society. In this paper, an attempt has been made to focus the issues on international organisations with regard to good governance.

Keywords: good governance, World Trade Organisation, international organisation, governance reforms

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950 A Hybrid of BioWin and Computational Fluid Dynamics Based Modeling of Biological Wastewater Treatment Plants for Model-Based Control

Authors: Komal Rathore, Kiesha Pierre, Kyle Cogswell, Aaron Driscoll, Andres Tejada Martinez, Gita Iranipour, Luke Mulford, Aydin Sunol

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Modeling of Biological Wastewater Treatment Plants requires several parameters for kinetic rate expressions, thermo-physical properties, and hydrodynamic behavior. The kinetics and associated mechanisms become complex due to several biological processes taking place in wastewater treatment plants at varying times and spatial scales. A dynamic process model that incorporated the complex model for activated sludge kinetics was developed using the BioWin software platform for an Advanced Wastewater Treatment Plant in Valrico, Florida. Due to the extensive number of tunable parameters, an experimental design was employed for judicious selection of the most influential parameter sets and their bounds. The model was tuned using both the influent and effluent plant data to reconcile and rectify the forecasted results from the BioWin Model. Amount of mixed liquor suspended solids in the oxidation ditch, aeration rates and recycle rates were adjusted accordingly. The experimental analysis and plant SCADA data were used to predict influent wastewater rates and composition profiles as a function of time for extended periods. The lumped dynamic model development process was coupled with Computational Fluid Dynamics (CFD) modeling of the key units such as oxidation ditches in the plant. Several CFD models that incorporate the nitrification-denitrification kinetics, as well as, hydrodynamics was developed and being tested using ANSYS Fluent software platform. These realistic and verified models developed using BioWin and ANSYS were used to plan beforehand the operating policies and control strategies for the biological wastewater plant accordingly that further allows regulatory compliance at minimum operational cost. These models, with a little bit of tuning, can be used for other biological wastewater treatment plants as well. The BioWin model mimics the existing performance of the Valrico Plant which allowed the operators and engineers to predict effluent behavior and take control actions to meet the discharge limits of the plant. Also, with the help of this model, we were able to find out the key kinetic and stoichiometric parameters which are significantly more important for modeling of biological wastewater treatment plants. One of the other important findings from this model were the effects of mixed liquor suspended solids and recycle ratios on the effluent concentration of various parameters such as total nitrogen, ammonia, nitrate, nitrite, etc. The ANSYS model allowed the abstraction of information such as the formation of dead zones increases through the length of the oxidation ditches as compared to near the aerators. These profiles were also very useful in studying the behavior of mixing patterns, effect of aerator speed, and use of baffles which in turn helps in optimizing the plant performance.

Keywords: computational fluid dynamics, flow-sheet simulation, kinetic modeling, process dynamics

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949 Global Supply Chain Tuning: Role of National Culture

Authors: Aleksandr S. Demin, Anastasiia V. Ivanova

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Purpose: The current economy tends to increase the influence of digital technologies and diminish the human role in management. However, it is impossible to deny that a person still leads a business with its own set of values and priorities. The article presented aims to incorporate the peculiarities of the national culture and the characteristics of the supply chain using the quantitative values of the national culture obtained by the scholars of comparative management (Hofstede, House, and others). Design/Methodology/Approach: The conducted research is based on the secondary data in the field of cross-country comparison achieved by Prof. Hofstede and received in the GLOBE project. The data mentioned are used to design different aspects of the supply chain both on the cross-functional and inter-organizational levels. The connection between a range of principles in general (roles assignment, customer service prioritization, coordination of supply chain partners) and in comparative management (acknowledgment of the national peculiarities of the country in which the company operates) is shown over economic and mathematical models, mainly linear programming models. Findings: The combination of the team management wheel concept, the business processes of the global supply chain, and the national culture characteristics let a transnational corporation to form a supply chain crew balanced in costs, functions, and personality. To elaborate on an effective customer service policy and logistics strategy in goods and services distribution in the country under review, two approaches are offered. The first approach relies exceptionally on the customer’s interest in the place of operation, while the second one takes into account the position of the transnational corporation and its previous experience in order to accord both organizational and national cultures. The effect of integration practice on the achievement of a specific supply chain goal in a specific location is advised to assess via types of correlation (positive, negative, non) and the value of national culture indices. Research Limitations: The models developed are intended to be used by transnational companies and business forms located in several nationally different areas. Some of the inputs to illustrate the application of the methods offered are simulated. That is why the numerical measurements should be used with caution. Practical Implications: The research can be of great interest for the supply chain managers who are responsible for the engineering of global supply chains in a transnational corporation and the further activities in doing business on the international area. As well, the methods, tools, and approaches suggested can be used by top managers searching for new ways of competitiveness and can be suitable for all staff members who are keen on the national culture traits topic. Originality/Value: The elaborated methods of decision-making with regard to the national environment suggest the mathematical and economic base to find a comprehensive solution.

Keywords: logistics integration, logistics services, multinational corporation, national culture, team management, service policy, supply chain management

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948 Study of the Tribological Behavior of a Pin on Disc Type of Contact

Authors: S. Djebali, S. Larbi, A. Bilek

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The present work aims at contributing to the study of the complex phenomenon of wear of pin on disc contact in dry sliding friction between two material couples (bronze/steel and unsaturated polyester virgin and charged with graphite powder/steel). The work consists of the determination of the coefficient of friction, the study of the influence of the tribological parameters on this coefficient and the determination of the mass loss and the wear rate of the pin. This study is also widened to the highlighting of the influence of the addition of graphite powder on the tribological properties of the polymer constituting the pin. The experiments are carried out on a pin-disc type tribometer that we have designed and manufactured. Tests are conducted according to the standards DIN 50321 and DIN EN 50324. The discs are made of annealed XC48 steel and quenched and tempered XC48 steel. The main results are described here after. The increase of the normal load and the sliding speed causes the increase of the friction coefficient, whereas the increase of the percentage of graphite and the hardness of the disc surface contributes to its reduction. The mass loss also increases with the normal load. The influence of the normal load on the friction coefficient is more significant than that of the sliding speed. The effect of the sliding speed decreases for large speed values. The increase of the amount of graphite powder leads to a decrease of the coefficient of friction, the mass loss and the wear rate. The addition of graphite to the UP resin is beneficial; it plays the role of solid lubricant.

Keywords: bronze, friction coefficient, graphite, mass loss, polyester, steel, wear rate

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947 Economic Integration in Eurasia: Modeling of the Current and Future Architecture

Authors: M. G. Shilina

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The prospects for political and economic development of the Eurasian space are currently discussed at both governmental and expert levels. New concepts actively proposed by the Eurasian governments require the analysis and search for effective implementation options. In the paper, an attempt to identify effective solutions to the problems surrounding the current economic integration of the Eurasian states is given on the basis of an interdisciplinary, comprehensive, structured analysis. The phenomenon is considered through the prism of the international law, world economy and politics, combined with the study of existing intergovernmental practice. The modeling method was taken as the basis for the research and is supplemented by legal and empirical methods. The detailed multi-level model of practical construction the 'Great Eurasia' (the GE) concept is proposed, the option for building a phased interaction in Eurasia is given through the prism of construction by the Eurasian Economic Union (the EAEU) as the main tool. The Shanghai Cooperation Organization (the SCO) is seen as the most promising element of the model. The SCO is capable of streamlining the formation of the GE and determine the transformation of Eurasia into a common economic space. Effective development of the economic integration between Eurasian states on the framework of the SCO is optimal. The SCO+ could be used as a platform for integration-integration processes formation. The creation of stable financial ties could become the basis for the possible formation of an expanded transregional integration platform. The paper concludes that the implementation of the proposed model could entail a gradual economic rapprochement of Eurasia and beyond.

Keywords: economic integration, The Eurasian Economic Union, The European Union, The Shanghai Cooperation Organization, the silk road economic belt

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946 A Historical Overview and Supplementation of the Dyad Concept of Industrial Marketing

Authors: Kimmo J. Kurppa

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This paper describes the development of the buyer-supplier dyad concept over the years and proposes improvements, clarifications and extensions to the prevailing definitions published in 1970’s and 1980’s. This paper suggests a partition of the buyer-supplier dyad to concepts of Commercial Dyad (dyadic interaction in vertical relationships) and Innovative Dyad (dyadic interaction in horizontal relationship) since dyadic interaction takes place in two major types of contexts between industrial firms. Especially the context of joint product development in a dyadic relationship has not been adequately recognized being totally different from the interaction taking place in commercial buyer-supplier interaction. This paper provides therefore a solution to the existing gap in research by clarifying the descriptions and the context where dyadic interaction takes place between industrial firms. This paper also illustrates and explains how the firm’s organization and the interaction taking place inside it, is connected to the dyadic interaction structure between the firm and its partner firm. This theme has been discussed earlier but the phenomenon has not been adequately described and has not been illustrated in earlier research. This conceptual study has been interested in how the dyad concept of Industrial Marketing has been defined in the earlier research and how the definition could be improved. This conceptual paper has been constructed by using the systematic review methodology and proposes avenues for future research. The concept and existence of relationship and interaction between firm’s internal interaction network and external interaction between firm’s dyadic counterparts, need to be verified through empirical research.

Keywords: dyadic interaction, industrial dyad, buyer-supplier relationship, strategic reciprocity, experience, socially adjusted opportunism

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945 The Inversion of Helical Twist Sense in Liquid Crystal by Spectroscopy Methods

Authors: Anna Drzewicz, Marzena Tykarska

Abstract:

The chiral liquid crystal phases form the helicoidal structure, which is characterized by the helical pitch and the helical twist sense. In anticlinic smectic phase with antiferroelectric properties three types of helix temperature dependence have been obtained: increased helical pitch with temperature and right-handed helix, decreased helical pitch with temperature and left-handed helix and the inversion of both. The change of helical twist sense may be observed during the transition from one liquid crystal phase to another or within one phase for the same substance. According to Gray and McDonnell theory, the helical handedness depends on the absolute configuration of the assymetric carbon atom and its position related to the rigid core of the molecule. However, this theory does not explain the inversion of helical twist sense phenomenon. It is supposed, that it may be caused by the presence of different conformers with opposite handendess, which concentration may change with temperature. In this work, the inversion of helical twist sense in the chiral liquid crystals differing in the length of alkyl chain, in the substitution the benzene ring by fluorine atoms and in the type of helix handedness was tested by vibrational spectroscopy (infrared and raman spectroscopy) and by nuclear magnetic resonance spectroscopy. The results obtained from the vibrational spectroscopy confirm the presence of different conformers. Moreover, the analysis of nuclear magnetic resonance spectra is very useful to check, on which structural fragments the change of conformations are important for the change of helical twist sense.

Keywords: helical twist sense, liquid crystals, nuclear magnetic resonance spectroscopy, vibrational spectroscopy

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944 A Contemplation of Iranian Islamic Architecture in the Age of Globalization

Authors: Maziar Asefi, Safa Salkhi Khasraghi

Abstract:

Despite the great development of Islamic Architecture in its conquered lands, its active performance in a vast geographical area, faded by the advent of industrial age. Now in the Information Age with great advances in technologies and increased interconnection among many societies, every aspect of life is affected by rapid spreading phenomenon called globalization which resulted in the world with less regional and cultural boundaries. So being proudly globalized in the past and becoming inactive in today's globalized world puts Islamic Architecture in a great challenge. Indeed, its important role has changed from transmitting cultural values to the world to importing dominated values even defectively. This study aimed to determine the factors influenced this controversial situation of Islamic Architecture, especially in current age. The paper focuses on performance of Islamic architecture in relation with Globalization as an ancient process. So qualitative method in terms of logic analysis was chosen to evaluate how Islamic architecture of Iran has contributed in Globalization subject in different time periods. Several works were analyzed as case studies in three categories: religious, monumental, commercial utilities and climate element. Theoretical and practical findings indicate that there is a mutual relationship between Islamic Architecture and Globalization which is transformed from the active mode to passive mode gradually in three periods of Globalization: proto, modern and communication Globalization. The proposed solution in the response to this challenge is finding a solution that makes an equilibrium between science, art, and technology, as well as taking the global performance of architecture.

Keywords: Islamic architecture, globalisation, the relationship among art, science and technology, Iranian architecture

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943 Probabilistic Models to Evaluate Seismic Liquefaction In Gravelly Soil Using Dynamic Penetration Test and Shear Wave Velocity

Authors: Nima Pirhadi, Shao Yong Bo, Xusheng Wan, Jianguo Lu, Jilei Hu

Abstract:

Although gravels and gravelly soils are assumed to be non-liquefiable because of high conductivity and small modulus; however, the occurrence of this phenomenon in some historical earthquakes, especially recently earthquakes during 2008 Wenchuan, Mw= 7.9, 2014 Cephalonia, Greece, Mw= 6.1 and 2016, Kaikoura, New Zealand, Mw = 7.8, has been promoted the essential consideration to evaluate risk assessment and hazard analysis of seismic gravelly soil liquefaction. Due to the limitation in sampling and laboratory testing of this type of soil, in situ tests and site exploration of case histories are the most accepted procedures. Of all in situ tests, dynamic penetration test (DPT), Which is well known as the Chinese dynamic penetration test, and shear wave velocity (Vs) test, have been demonstrated high performance to evaluate seismic gravelly soil liquefaction. However, the lack of a sufficient number of case histories provides an essential limitation for developing new models. This study at first investigates recent earthquakes that caused liquefaction in gravelly soils to collect new data. Then, it adds these data to the available literature’s dataset to extend them and finally develops new models to assess seismic gravelly soil liquefaction. To validate the presented models, their results are compared to extra available models. The results show the reasonable performance of the proposed models and the critical effect of gravel content (GC)% on the assessment.

Keywords: liquefaction, gravel, dynamic penetration test, shear wave velocity

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942 Study and Simulation of the Thrust Vectoring in Supersonic Nozzles

Authors: Kbab H, Hamitouche T

Abstract:

In recent years, significant progress has been accomplished in the field of aerospace propulsion and propulsion systems. These developments are associated with efforts to enhance the accuracy of the analysis of aerothermodynamic phenomena in the engine. This applies in particular to the flow in the nozzles used. One of the most remarkable processes in this field is thrust vectoring by means of devices able to orientate the thrust vector and control the deflection of the exit jet in the engine nozzle. In the study proposed, we are interested in the fluid thrust vectoring using a second injection in the nozzle divergence. This fluid injection causes complex phenomena, such as boundary layer separation, which generates a shock wave in the primary jet upstream of the fluid interacting zone (primary jet - secondary jet). This will cause the deviation of the main flow, and therefore of the thrust vector with reference to the axis nozzle. In the modeling of the fluidic thrust vector, various parameters can be used. The Mach number of the primary jet and the injected fluid, the total pressures ratio, the injection rate, the thickness of the upstream boundary layer, the injector position in the divergent part, and the nozzle geometry are decisive factors in this type of phenomenon. The complexity of the latter challenges researchers to understand the physical phenomena of the turbulent boundary layer encountered in supersonic nozzles, as well as the calculation of its thickness and the friction forces induced on the walls. The present study aims to numerically simulate the thrust vectoring by secondary injection using the ANSYS-FLUENT, then to analyze and validate the results and the performances obtained (angle of deflection, efficiency...), which will then be compared with those obtained by other authors.

Keywords: CD Nozzle, TVC, SVC, NPR, CFD, NPR, SPR

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941 Sonication as a Versatile Tool for Photocatalysts’ Synthesis and Intensification of Flow Photocatalytic Processes Within the Lignocellulose Valorization Concept

Authors: J. C. Colmenares, M. Paszkiewicz-Gawron, D. Lomot, S. R. Pradhan, A. Qayyum

Abstract:

This work is a report of recent selected experiments of photocatalysis intensification using flow microphotoreactors (fabricated by an ultrasound-based technique) for photocatalytic selective oxidation of benzyl alcohol (BnOH) to benzaldehyde (PhCHO) (in the frame of the concept of lignin valorization), and the proof of concept of intensifying a flow selective photocatalytic oxidation process by acoustic cavitation. The synthesized photocatalysts were characterized by using different techniques such as UV-Vis diffuse reflectance spectroscopy, X-ray diffraction, nitrogen sorption, thermal gravimetric analysis, and transmission electron microscopy. More specifically, the work will be on: a Design and development of metal-containing TiO₂ coated microflow reactor for photocatalytic partial oxidation of benzyl alcohol: The current work introduces an efficient ultrasound-based metal (Fe, Cu, Co)-containing TiO₂ deposition on the inner walls of a perfluoroalkoxy alkanes (PFA) microtube under mild conditions. The experiments were carried out using commercial TiO₂ and sol-gel synthesized TiO₂. The rough surface formed during sonication is the site for the deposition of these nanoparticles in the inner walls of the microtube. The photocatalytic activities of these semiconductor coated fluoropolymer based microreactors were evaluated for the selective oxidation of BnOH to PhCHO in the liquid flow phase. The analysis of the results showed that various features/parameters are crucial, and by tuning them, it is feasible to improve the conversion of benzyl alcohol and benzaldehyde selectivity. Among all the metal-containing TiO₂ samples, the 0.5 at% Fe/TiO₂ (both, iron and titanium, as cheap, safe, and abundant metals) photocatalyst exhibited the highest BnOH conversion under visible light (515 nm) in a microflow system. This could be explained by the higher crystallite size, high porosity, and flake-like morphology. b. Designing/fabricating photocatalysts by a sonochemical approach and testing them in the appropriate flow sonophotoreactor towards sustainable selective oxidation of key organic model compounds of lignin: Ultrasonication (US)-assitedprecipitaion and US-assitedhydrosolvothermal methods were used for the synthesis of metal-oxide-based and metal-free-carbon-based photocatalysts, respectively. Additionally, we report selected experiments of intensification of a flow photocatalytic selective oxidation through the use of ultrasonic waves. The effort of our research is focused on the utilization of flow sonophotocatalysis for the selective transformation of lignin-based model molecules by nanostructured metal oxides (e.g., TiO₂), and metal-free carbocatalysts. A plethora of parameters that affects the acoustic cavitation phenomena, and as a result the potential of sonication were investigated (e.g. ultrasound frequency and power). Various important photocatalytic parameters such as the wavelength and intensity of the irradiated light, photocatalyst loading, type of solvent, mixture of solvents, and solution pH were also optimized.

Keywords: heterogeneous photo-catalysis, metal-free carbonaceous materials, selective redox flow sonophotocatalysis, titanium dioxide

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940 Functionalized Titanium Dioxide Nanoparticles for Targeting and Disrupting Amyloid Fibrils

Authors: Elad Arad, Raz Jelinek, Hanna Rapaport

Abstract:

Amyloidoses are a family of diseases characterized by abnormal protein folding that leads to aggregation. They accumulate to form fibrillar plaques which are implicated in the pathogenesis of Alzheimer, prion, diabetes type II and other diseases. To the best of our knowledge, despite extensive research efforts devoted to plaque aggregates inhibition, there is yet no cure for this phenomenon. Titanium and its alloys are found in growing interest for biomedical applications. Variety of surface modifications enable porous, adhesive, bioactive coatings for its surface. Titanium oxides (titania) are also being developed for photothermal and photodynamic treatments. Inspired by this, we set to explore the effect of functionalized titania nanoparticles in combination with external stimuli, as potential photothermal ablating agents against amyloids. Titania nanoparticles were coated with bi-functional catechol derivatives (dihydroxy-phenylalanine propanoic acid, noted DPA) to gain targeting properties. In conjunction with UV-radiation, these nanoparticles may selectively destroy the vicinity of their target. Titania modified 5 nm nanoparticles coated with DPA were further conjugated to the amyloid-targeting Congo Red (CR). These Titania-DPA-CR nanoparticles were found to target mature amyloid fibril of both amyloid-β (Aβ 1-42 a.a). Moreover, irradiation of the peptides in presence of the modified nanoparticles decreased the aggregate content and oligomer fraction. This work provides insights into the use of modified titania nanoparticles for amyloid plaque targeting and photothermal destruction. It may shed light on future modifications and functionalization of titania nanoparticles for different applications.

Keywords: titanium dioxide, amyloids, photothermal treatment, catechol, Congo-red

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939 Multi-Level Framework for Effective Use of Stock Ordering System: Case Study of Small Enterprises in Kgautswane

Authors: Lethamaga Tladi, Ray Kekwaletswe

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This study sought to conceptualise a multi-level framework for the effective use of stock ordering system in small enterprises in a rural area context. The interpretive research methodology has been used to enable the researcher to analyse, in-depth, and the subjective meanings of small enterprises’ employees in using the stock ordering system. The empirical data was collected from 13 small enterprises’ employees as participants through semi-structured interviews and observations. Interpretive Phenomenological Analysis (IPA) approach was used to analyse the small enterprises’ employee’s own account of lived experiences in relations to stock ordering system use in terms of their relatedness to, and cognitive engagement with. A case study of Kgautswane, a rural area in Limpopo Province, South Africa, served as a social context where the phenomenon manifested. Technology-Organisation-Environment Theory (TOE), Technology-to-Performance Chain Model (TPC), and Representation Theory (RT) underpinned this study. In this multi-level study, the findings revealed that; At the organisational level, the effective use of stock ordering system was found to be associated with the organisational performance gains such as efficiency, productivity, quality, competitiveness, and market share. Equally so, at the individual level, the effective use of stock ordering system minimised the end-user’s efforts and time to accomplish their tasks, which yields improved individual performance. The Multi-level framework for effective use of stock ordering system was presented.

Keywords: effective use, multi-dimensions of use, multi-level of use, multi-level research, small enterprises, stock ordering system

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938 The Immediate Effects of Thrust Manipulation for Thoracic Hyperkyphosis

Authors: Betul Taspinar, Eda O. Okur, Ismail Saracoglu, Ismail Okur, Ferruh Taspinar

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Thoracic hyperkyphosis, is a well-known spinal phenomenon, refers to an excessive curvature (> 40 degrees) of the thoracic spine. The aim of this study was to explore the effectiveness of thrust manipulation on thoracic spine alignment. 31 young adults with hyperkyphosis diagnosed with Spinal Mouse® device were randomly assigned either thrust manipulation group (n=16, 11 female, 5 male) or sham manipulation group (n=15, 8 female, 7 male). Thrust and sham manipulations were performed by a blinded physiotherapist who is a certificated expert in musculoskeletal physiotherapy. Thoracic kyphosis degree was measured after the interventions via Spinal Mouse®. Wilcoxon test was used to analyse the data obtained before and after the manipulation for each group, whereas Mann-Whitney U test was used to compare the groups. The mean of baseline thoracic kyphosis degrees in thrust and sham groups were 50.69 o ± 7.73 and 48.27o ± 6.43, respectively. There was no statistically significant difference between groups in terms of initial thoracic kyphosis degrees (p=0.51). After the interventions, the mean of thoracic kyphosis degree in thrust and sham groups were measured as 44.06o ± 6.99 and 48.93o ± 6.57 respectively (p=0.03). There was no statistically significant difference between before and after interventions in sham group (p=0.33), while the mean of thoracic kyphosis degree in thrust group decreased significantly (p=0.00). Thrust manipulation can attenuate thoracic hyperkyphosis immediately in young adults by not using placebo effect. Manipulation might provide accurate proprioceptive (sensory) input to the spine joints and reduce kyphosis by restoring normal segment mobility. Therefore thoracic manipulation might be included in the physiotherapy programs to treat hyperkyphosis.

Keywords: hyperkyphosis, manual therapy, spinal mouse, physiotherapy

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937 Liesegang Phenomena: Experimental and Simulation Studies

Authors: Vemula Amalakrishna, S. Pushpavanam

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Change and motion characterize and persistently reshape the world around us, on scales from molecular to global. The subtle interplay between change (Reaction) and motion (Diffusion) gives rise to an astonishing intricate spatial or temporal pattern. These pattern formation in nature has been intellectually appealing for many scientists since antiquity. Periodic precipitation patterns, also known as Liesegang patterns (LP), are one of the stimulating examples of such self-assembling reaction-diffusion (RD) systems. LP formation has a great potential in micro and nanotechnology. So far, the research on LPs has been concentrated mostly on how these patterns are forming, retrieving information to build a universal mathematical model for them. Researchers have developed various theoretical models to comprehensively construct the geometrical diversity of LPs. To the best of our knowledge, simulation studies of LPs assume an arbitrary value of RD parameters to explain experimental observation qualitatively. In this work, existing models were studied to understand the mechanism behind this phenomenon and challenges pertaining to models were understood and explained. These models are not computationally effective due to the presence of discontinuous precipitation rate in RD equations. To overcome the computational challenges, smoothened Heaviside functions have been introduced, which downsizes the computational time as well. Experiments were performed using a conventional LP system (AgNO₃-K₂Cr₂O₇) to understand the effects of different gels and temperatures on formed LPs. The model is extended for real parameter values to compare the simulated results with experimental data for both 1-D (Cartesian test tubes) and 2-D(cylindrical and Petri dish).

Keywords: reaction-diffusion, spatio-temporal patterns, nucleation and growth, supersaturation

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936 Rehabilitation and Conservation of Mangrove Forest as Pertamina Corporate Social Responsibility Approach in Prevention Damage Climate in Indonesia

Authors: Nor Anisa

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This paper aims to describe the use of conservation and rehabilitation of Mangrove forests as an alternative area in protecting the natural environment and ecosystems and ecology, community education and innovation of sustainable industrial development such as oil companies, gas and coal. The existence of globalization encourages energy needs such as gas, diesel and coal as an unaffected resource which is a basic need for human life while environmental degradation and natural phenomena continue to occur in Indonesia, especially global warming, sea water pollution, extinction of animal steps. The phenomenon or damage to nature in Indonesia is caused by a population explosion in Indonesia that causes unemployment, the land where the residence will disappear so that this will encourage the exploitation of nature and the environment. Therefore, Pertamina as a state-owned oil and gas company carries out its social responsibility efforts, namely to carry out conservation and rehabilitation and management of Mangrove fruit seeds which will provide an educational effect on the benefits of Mangrove seed maintenance. The method used in this study is a qualitative method and secondary data retrieval techniques where data is taken based on Pertamina activity journals and websites that can be accounted for. So the conclusion of this paper is: the benefits and function of conservation of mangrove forests in Indonesia physically, chemically, biologically and socially and economically and can provide innovation to the CSR (Corporate Social Responsibility) of the company in continuing social responsibility in the scope of environmental conservation and social education.

Keywords: mangrove, environmental damage, conservation and rehabilitation, innovation of corporate social responsibility

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935 Performance and Processing Evaluation of Solid Oxide Cells by Co-Sintering of GDC Buffer Layer and LSCF Air Electrode

Authors: Hyun-Jong Choi, Minjun Kwak, Doo-Won Seo, Sang-Kuk Woo, Sun-Dong Kim

Abstract:

Solid Oxide Cell(SOC) systems can contribute to the transition to the hydrogen society by utilized as a power and hydrogen generator by the electrochemical reaction with high efficiency at high operation temperature (>750 ℃). La1-xSrxCo1-yFeyO3, which is an air electrode, is occurred stability degradations due to reaction and delamination with yittria stabilized zirconia(YSZ) electrolyte in a water electrolysis mode. To complement this phenomenon SOCs need gadolinium doped ceria(GDC) buffer layer between electrolyte and air electrode. However, GDC buffer layer requires a high sintering temperature and it causes a reaction with YSZ electrolyte. This study carried out low temperature sintering of GDC layer by applying Cu-oxide as a sintering aid. The effect of a copper additive as a sintering aid to lower the sintering temperature for the construction of solid oxide fuel cells (SOFCs) was investigated. GDC buffer layer with 0.25-10 mol% CuO sintering aid was prepared by reacting GDC power and copper nitrate solution followed by heating at 600 ℃. The sintering of CuO-added GDC powder was optimized by investigating linear shrinkage, microstructure, grain size, ionic conductivity, and activation energy of CuO-GDC electrolytes at temperatures ranging from 1100 to 1400 ℃. The sintering temperature of the CuO-GDC electrolyte decreases from 1400 ℃ to 1100 ℃ by adding the CuO sintering aid. The ionic conductivity of the CuO-GDC electrolyte shows a maximum value at 0.5 mol% of CuO. However, the addition of CuO has no significant effects on the activation energy of GDC electrolyte. GDC-LSCF layers were co-sintering at 1050 and 1100 ℃ and button cell tests were carried out at 750 ℃.

Keywords: Co-Sintering, GDC-LSCF, Sintering Aid, solid Oxide Cells

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