Search results for: black feminism

Authors: Dragos Ardeleanu, Silviu-Valentin Petre

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Written to satisfy the needs of Western powers, classical geopolitics bore the stint of Eurocentrism. Both Mackinder’s heartland and Nicholas Spykman’s rimland were intellectual creations set for the purpose of the Anglophone nations dealing with Eurasia. However, while today’s world is moving towards multipolarity, other emerging regional actors are following their own interests using a different geospatial map. Such is the case of Iran which has developed an engagement pattern in Africa, directed mostly towards costal states, in order to break the rimland grip of Arab states and also the international pressure established against Tehran’s nascent nuclear program. Capitalizing on literature review and analysing statements from key public figures, our paper argues that Iranian African geopolitics displays a dual message: on the one hand, it uses tiers-mondiste rhetoric to garner the support of different coastal African states and, on the other hand, it employs Shiism to gain a foothold in strategic parts of the black continent.

Keywords: African geopolitics, Iran, Shiism, tiers-mondisme

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Authors: Neda Navidi, Rene Jr. Landry

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Vehicle tracking and accident recognizing are considered by many industries like insurance and vehicle rental companies. The main goal of this paper is to detect the location of a car accident by combining different methods. The methods, which are considered in this paper, are Global Navigation Satellite Systems/Inertial Measurement Units (GNSS/IMU)-based navigation and vehicle accident detection algorithms. They are expressed by a set of raw measurements, which are obtained from a designed integrator black box using GNSS and inertial sensors. Another concern of this paper is the definition of accident detection algorithm based on its jerk to identify the position of that accident. In fact, the results convinced us that, even in GNSS blockage areas, the position of the accident could be detected by GNSS/INS integration with 50% improvement compared to GNSS stand alone.

Keywords: driver behavior monitoring, integration, IMU, GNSS, monitoring, tracking

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Authors: Lara Góes Da Costa

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This paper analyzes the social dimension of the empowerment of women in Brazil, following the principles of human development of the UN WOMEN, in particular the sixth principle, which establishes the promotion of gender equality through social policy initiatives and activism in general aimed at community. In Brazil, women's empowerment has taken social networks through the creation of avatars and pages of dissemination and promotion of gender equality, as well as denunciations and educational posts such as 'Observe Gender', 'Empower Two Women', 'Black Intellectual Women', among others. At the same time, women's social inclusion bills in various sectors are trailing in the legislative apparatus, with little or no relation to the current discussion of gender diversity and intersectionality. In this sense, this article establishes an analytical parallel between the media manifestations of social networks and the social distance of the representatives of the legislative power. This parallelly shows the political failing to meet the social demands of inclusion, as to multiply the creation of laws and the effectiveness of the principle of promoting gender equality.

Keywords: gender, rights, justice, social networks

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Authors: Sophia Francesca D. Lu

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This research tried to produce evidence that formal institutions, such as electoral and internal party quotas, can advance women’s active roles in the public sphere using the cases of four European countries: Belgium, Germany, Italy, and the Netherlands. The quantitative dataset was provided by the University of Chicago and the Inter-University Consortium of Political and Social Research based on a two-year study (2008-2010) of political parties. Belgium engages in constitutionally mandated electoral quotas. Germany, Italy and the Netherlands, on the other hand, have internal party quotas, which are voluntarily adopted by political parties. In analyzing each country’s chi-square and Pearson’s r correlation, Belgium, having an electoral quota, is the only country that was analyzed for electoral quotas. Germany, Italy and the Netherlands’ internal voluntary party quotas were correlated with women’s descriptive representations. Using chi-square analysis, this study showed that the presence of electoral quotas is correlated with an increase in the percentage of women in decision-making bodies as well as with an increase in the percentage of women in decision-making bodies. Likewise, using correlational analysis, a higher number of political parties employing internal party voluntary quotas is correlated with an increase in the percentage of women occupying seats in parliament as well as an increase in the percentage of women nominees in electoral lists of political parties. In conclusion, gender quotas, such as electoral quotas or internal party quotas, are an effective policy tool for greater women’s representation in political bodies. Political parties and governments should opt to have gender quotas, whether electoral or internal party quotas, to address the underrepresentation of women in parliament, decision-making bodies, and policy-formulation.

Keywords: electoral quota, Europe, formal institutions, institutional feminism, internal party quota, women’s electoral participation

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Authors: P. Mormile, M. Rippa, G. Bonanomi, F. Scala, Changrong Yan, L. Petti

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Photo-reflective films represent, in the panorama of agricultural films, a valid support for Spring and Summer cultivations, both in open field and under greenhouse. In fact, thanks to the high reflectivity of these films, thermal aggression, that causes serious problems to plants when traditional black mulch films are used, is avoided. Yellow or silver colored photo-reflective films protect plants from damages, assure the mulching effect, give a valid support to Integrated Pest Management and, according to recent trials, greatly contribute in saving water. This further advantage is determined by the high water condensation under the mulch film and this gives rise to reduction of irrigation. Water saving means also energy saving for electric system of water circulation. Trials performed at different geographic and ambient context confirm that the use of photo-reflective mulch films during the hot season allows to save water up to 30%.

Keywords: photo-selective mulches, saving water, water circulation, irrigation

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Authors: Sara Kanzi, Izzet Sakalli

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The effect of Lorentz symmetry breaking (LSB) on the Hawking radiation of Schwarzschild-like black hole found in the bumblebee gravity model (SBHBGM) is studied in the framework of quantum gravity. To this end, we consider Hawking radiation spin-0 (bosons) and spin-12particles (fermions), which go in and out through the event horizon of the SBHBGM. We use the modified Klein-Gordon and Dirac equations, which are obtained from the generalized uncertainty principle (GUP) to show how Hawking radiation is affected by the GUP and LSB. In particular, we reveal that independent of the spin of the emitted particles, GUP causes a change in the Hawking temperature of the SBHBGM. Furthermore, we compute the semi-analytic greybody factors (for both bosons and fermions) of the SBHBGM. Thus, we reveal that LSB is effective on the greybody factor of the SBHBGM such that its redundancy decreases the value of the greybody factor. Our findings are graphically depicted.

Keywords: bumblebee gravity model, Hawking radiation, generalized uncertainty principle, Lorentz symmetry breaking

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Authors: Amhimmid Mohammed Saffour, Abdelkader Salama

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Filtering is a part of image enhancement techniques, it is used to enhance certain details such as edges in the image that are relevant to the application. Additionally, filtering can even be used to eliminate unwanted components of noise. Medical images typically contain salt and pepper noise and Poisson noise. This noise appears to the presence of minute grey scale variations within the image. In this paper, different filters techniques namely (Median, Wiener, Rank order3, Rank order5, and Average) were applied on CT medical images (Brain and chest). We using all these filters to remove salt and pepper noise from these images. This type of noise consists of random pixels being set to black or white. Peak Signal to Noise Ratio (PSNR), Mean Square Error r(MSE) and Histogram were used to evaluated the quality of filtered images. The results, which we have achieved shows that, these filters, are more useful and they prove to be helpful for general medical practitioners to analyze the symptoms of the patients with no difficulty.

Keywords: CT imaging, median filter, adaptive filter and average filter, MATLAB

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Authors: Anvar Atayev, Karl Steinborn, Aleksander Lovric, Saif Al-Ibadi, Jorg Fliege

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In this paper, we present results obtained from optimising the aerodynamic performance of aerostructures in external ow. The optimisation method used was developed to efficiently handle multi-variable problems with numerous black-box objective functions and constraints. To demonstrate these capabilities, a series of CFD problems were considered; (1) a two-dimensional NACA aerofoil with three variables, (2) a two-dimensional morphing aerofoil with 17 variables, and (3) a three-dimensional morphing aeroplane tail with 33 variables. The objective functions considered were related to combinations of the mean aerodynamic coefficients, as well as their relative variations/oscillations. It was observed that for each CFD problem, an improved objective value was found. Notably, the scale-up in variables for the latter problems did not greatly hinder optimisation performance. This makes the method promising for scaled-up CFD problems, which require considerable computational resources.

Keywords: computational fluid dynamics, optimisation algorithms, aerodynamic design, engineering design

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Authors: Jing-Gang Xie

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The research, in this case, considers the integration of the Quantum Field Theory and the General Relativity Theory. As two successful models in explaining behaviors of particles, they are incompatible since they work at different masses and scales of energy, with the evidence that regards the description of black holes and universe formation. It is so considering previous efforts in merging the two theories, including the likes of the String Theory, Quantum Gravity models, and others. In a bid to prove an actionable experiment, the paper’s approach starts with the derivations of the existing theories at present. It goes on to test the derivations by applying the same initial assumptions, coupled with several deviations. The resulting equations get similar results to those of classical Newton model, quantum mechanics, and general relativity as long as conditions are normal. However, outcomes are different when conditions are extreme, specifically with no breakdowns even for less than Schwarzschild radius, or at Planck length cases. Even so, it proves the possibilities of integrating the two theories.

Keywords: general relativity theory, particles, photons, Quantum Gravity Model, gravitational frequency shift

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Authors: Leah Wilck

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Eyewitness identification is arguably one of the most utilized practices within our legal system; however, exoneration cases indicate that this practice may lead to accuracy and conviction errors. The purpose of this study was to examine the effects of the cross-race effect, the phenomena in which people are able to more easily and accurately identify faces from within their racial category, on the accuracy of eyewitness identification. Participants watched three separate videos of a perpetrator trying to steal a bicycle. In each video, the perpetrator was of a different race and gender. Participants watched a video where the perpetrator was a Black male, a White male, and a White female. Following the completion of watching each video, participants were asked to recall everything they could about the perpetrator they witnessed. The initial results of the study did not find the expected cross-race effect impacted the eyewitness identification accuracy. These surprising results are discussed in terms of cross-race bias and recognition theory as well as applied implications.

Keywords: cross race effect, eyewitness identification, own-race bias, racial profiling

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Authors: Henry Lee, Daniel Shiu

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Educational organizations are currently exploring ways to increase equity, diversity, and inclusion (EDI), and this is now evident within the K-12 school system, universities, and teacher unions. These organizations have been creating and implementing new EDI specific policies. Their goal is to provide the framework and supports needed to establish EDI into the organizational culture. However, the implementation of EDI policies does not always lead to the intended outcomes. The purpose of this paper is to explore some factors regarding why the implementation of EDI policies within educational organizations can be problematic. This includes how Whiteness is replicated, promoted, and celebrated in educational leadership. How Whiteness and White supremacy are operationalized by BIPOC leaders within educational spaces, and how EDI specific training fails to understand the different training needed for both IBPOC (Indigenous, Black, People of Colour) and non-IBPOC leaders. This paper also addresses the model minority myth and how this informs and guides IBPOC identity and leadership within a predominately White dominant leadership in education.

Keywords: critical race theory, equity & diversity & inclusion, educational leadership, intersectionality

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Authors: Maryam Kiani

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The aim of this study was to investigate the influence of nanoparticles additive on the properties of fly ash-based geopolymer. The geopolymer samples were prepared using fly ash as the primary source material, along with an alkali activator solution and different concentrations of carbon black additive. The effects of nanoparticles flexural strength, water absorption, and micro-structural properties of the cured samples. The results revealed that the inclusion of nanoparticles additive significantly enhanced the mechanical and electrical properties of the geopolymer binder. Micro-structural analysis using scanning electron microscopy (SEM) revealed a more compact and homogeneous structure in the geopolymer samples with nanoparticles. The dispersion of nanoparticles particles within the geopolymer matrix was observed, suggesting improved inter-particle bonding and increased density. Overall, this study demonstrates the positive impact of nanoparticles additive on the qualities of fly ash-based geopolymer, emphasizing its potential as an effective enhancer for geopolymer binder applications for the development of construction and infrastructure for energy buildings.

Keywords: fly-ash, geopolymer, energy buildings, nanotechnology

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Authors: Nkeiruka Elsie Ezomike, Chinwe L. Onyekonwu, Anthony N. Ikefuna, Bede C. Ibe

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Superficial fungal infections (SFIs) are one of the common cutaneous infections that affect children worldwide. They may lead to school absenteeism or school drop-out and hence setback in the education of the child. Community-based studies in any locality are good reflections of the health conditions within that area. There is a dearth of information in the literature about SFI among primary school children in Enugu. This study aimed to determine the clinicomycological pattern of SFIs among primary school children in rural and urban communities in Enugu. This was a comparative descriptive cross-sectional study among primary school children in Awgu (rural) and Enugu North (urban) Local Government Areas (LGAs). Subjects' selection was made over 6 months using a multi-stage sampling method. Information such as age, sex, parental education, and occupation were collected using questionnaires. Socioeconomic classes of the children were determined using the classification proposed by Oyedeji et al. The samples were collected from subjects with SFIs. Potassium hydroxide tests were done on the samples. The samples that tested positive were cultured for SFI by inoculating onto Sabouraud's dextrose chloramphenicol actidione agar. The characteristics of the isolates were identified according to their morphological features using Mycology Online, Atlas 2000, and Mycology Review 2003. Equal numbers of children were recruited from the two LGAs. A total of 1662 pupils were studied. The mean ages of the study subjects were 9.03 ± 2.10years in rural and 10.46 ± 2.33years in urban communities. The male to female ratio was 1.6:1 in rural and 1:1.1 in urban communities. The personal hygiene of the children was significantly related to the presence of SFIs. The overall prevalence of SFIs among the study participants was 45%. In the rural, the prevalence was 29.6%, and in the urban prevalence was 60.4%. The types of SFIs were tinea capitis (the commonest), tinea corporis, pityriasis Versicolor, tinea unguium, and tinea manuum with prevalence rates lower in rural than urban communities. The clinical patterns were gray patch and black dot type of non-inflammatory tinea capitis, kerion, tinea corporis with trunk and limb distributions, and pityriasis Versicolor with face, trunk and limb distributions. Gray patch was the most frequent pattern of SFI seen in rural and urban communities. Black dot type was more frequent in rural than urban communities. SFIs were frequent among children aged 5 to 8years in rural and 9 to 12 years in urban communities. SFIs were commoner in males in the rural, whereas female dominance was observed in the urban. SFIs were more in children from low social class and those with poor hygiene. Trichophyton tonsurans and Trichophyton soudanese were the common mycological isolates in rural and urban communities, respectively. In conclusion, SFIs were less prevalent in rural than in urban communities. Trichophyton species were the most common fungal isolates in the communities. Health education of mothers and their children on SFI and good personal hygiene will reduce the incidence of SFIs.

Keywords: clinicomycological pattern, communities, primary school children, superficial fungal infections

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Authors: Bakr Ali Al-Gamrh, Ku Nor Izah B. Ku Ismail

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We investigate the relationship between corporate governance, leverage, risk, and firm performance. We use a firm level panel that spans the period 2008 to 2012 of all listed firms on Abu Dhabi Stock Exchange and Dubai Financial Market. After constructing an index of corporate governance strength, we find a negative effect of corporate governance on firm performance. We, however, discover that corporate governance strength indirectly improves the negative influence of leverage on firm performance in normal times. On the contrary, the results completely reversed when there is a black swan event. Corporate governance strength plays a significantly negative role in moderating the relationship between leverage and firm performance during the financial crisis. We also reveal that corporate governance strength increases firms’ risk and deteriorates performance during crisis. Results provide evidence that corporate governance indirectly plays a completely different role in different time periods.

Keywords: corporate governance, firm performance, risk, leverage, the UAE

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Authors: Sira Suren, Soorathep Kheawhom

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This work investigates the development of a high energy density zinc-air battery. Printed and flexible thin film zinc-air battery with an overall thickness of about 350 μm was fabricated by an inexpensive screen-printing technique. Commercial nano-silver ink was used as both current collectors and catalyst layer. Carbon black ink was used to fabricate cathode electrode. Polypropylene membrane was used as the cathode substrate and separator. 9 M KOH was used as the electrolyte. A mixture of Zn powder, ZnO, and Bi2O3 was used to prepare the anode electrode. The suitable concentration of Bi2O3 and types of binders (styrene-butadiene and sodium silicate) were investigated. Results showed that battery using 20% Bi2O3 and sodium silicate binder provided the best performance. The open-circuit voltage and energy density observed were 1.59 V and 690 Wh/kg, respectively. When the battery was discharged at 20 mA/cm2, the potential voltage observed was 1.3 V. Furthermore, the battery was tested for its flexibility. Upon bending, no significant loss in performance was observed.

Keywords: flexible, printed battery, screen printing, Zn-air

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Authors: Brianna Ross, John Sollers, Christopher Edwards

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In the age of heightened social and political discourse, there is a tendency for individuals and media sources to use dehumanization as a tool to influence group thoughts and attitudes. When considering individual interactions, there is a need to determine what characteristics increase or predict dehumanization. The present study investigated dehumanization tendencies related to social dominance orientation (SDO) and right-wing authoritarianism (RWA) while factoring in political affiliation. Two-hundred and seven individuals participated in an anonymous study to reveal that there was a significant relationship between high SDO and high RWA scores. There was also a significant correlation between the dehumanization of Black Lives Matter and SDO. These findings suggest that those who are “double high” (scoring highly on both SDO and RWA are more likely to dehumanize others, particularly social groups they disagree with. Acknowledging that there are significant changes occurring in the sociopolitical atmosphere, it is essential that researchers understand dehumanization tendencies in modern society to better define the concept of othering and its consequences on social interaction.

Keywords: dehumanization, social dominance orientation, right-wing authoritarianism, political affiliation

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Authors: Denise F. Brown

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This proposal provides an explanation of the content for a Special Topics Course to be offered Spring of 2022. The course will be titled, Creative means to address mental health in the African American Community: Arts, Advocacy, and Awareness. Research shows that African Americans are less likely to seek treatment for mental illnesses. The stigma around mental illness influences negative ideas about having psychological problems within the African American community. Assessments of how African Americans perceive mental illness will also be provided. Current research suggests that understanding mental health is just as important as understanding mental illness. The distinguishment between mental illness and mental health provides a way to not negatively point out mental illness but to better understand that psychological and emotional well-being can be achieved whether a mental illness is present or not. The course will consist of defining mental health and mental illness and then what it means to utilize creative means to become a mental health advocate within the African American community.

Keywords: arts, advocacy, black mental health, mental illness

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Authors: Noel Chellan

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Energy is the life-blood of development. All human societies have been and still are dependent on energy – some societies more than others. With regard to energy in South Africa, previous policies of the apartheid regime neglected the energy needs of poor black communities in general – and rural communities in particular. Since South Africa’s first democratic elections in 1994 – whilst millions of South African households have received electricity from the national electricity grid, there are still many rural communities that are still experiencing challenges in relation to both electricity deprivation as well as provision. This paper looks at the energy-mix of the Mnweni rural community in South Africa and argues that understanding energy is key to understanding the nature and forms of development of any community or country, for that matter. The paper engages with the energy trends in the rural community of Mnweni from the days of apartheid until 2021. It also looks at agricultural practises from an energy perspective. Such an energy perspective will enable one to assess the pace and scale of development in rural Mnweni.

Keywords: rural, energy, development, apartheid

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Authors: Kumar Sankaran, Santanu Chattopadhyay, Golok Behari Nando, Sujith Nair, Sreejesh Arayambath, Unnikrishnan Govindan

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Rubber nanocomposites based on Bromobutyl rubber (BIIR), Polyepichlorohydrin rubber (CO), Carbon black (CB) and organically modified montmorillonite clay (NC) were prepared via melt compounding technique. The developed quaternary nanocomposites were characterized analytically and their properties were compared against the standard BIIR compound. BIIR-CO nanocomposites showed improved physico-mechanical properties as compared to that of the standard BIIR compound. Hybrid microstructure (NC-CB) development, clay exfoliation and better filler dispersion in the quaternary nanocomposite significantly contributed to the overall enhancement of properties. Introduction of CO in the system increased the specific gravity and hardness of the compound as compared to that of the standard compound. XRD analysis, AFM imaging and HR-TEM measurements confirmed exfoliation and a good level of dispersion of the NC in the composites. Permeability of developed BIIR-CO nanocomposites decreases significantly as compared to that of the standard BIIR compound.

Keywords: rubber nanocomposites, morphology, permeability, BIIR

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Authors: Miroslav Popelka, Jakub Nožička

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In this paper we deal with using Lego Mindstorms in simulation of robotic systems with respect to cost reduction. Lego Mindstorms kit contains broad variety of hardware components which are required to simulate, program and test the robotics systems in practice. Algorithm programming went in development environment supplied together with Lego kit as in programming language C# as well. Algorithm following the line, which we dealt with in this paper, uses theoretical findings from area of controlling circuits. PID controller has been chosen as controlling circuit whose individual components were experimentally adjusted for optimal motion of robot tracking the line. Data which are determined to process by algorithm are collected by sensors which scan the interface between black and white surfaces followed by robot. Based on discovered facts Lego Mindstorms can be considered for low-cost and capable kit to simulate real robotics systems.

Keywords: LEGO Mindstorms, PID controller, low-cost robotics systems, line follower, sensors, programming language C#, EV3 Home Edition Software

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Authors: Salima Smiti, Ines Gasmi, Makram Soui

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Credit risk is the most important issue for financial institutions. Its assessment becomes an important task used to predict defaulter customers and classify customers as good or bad payers. To this objective, numerous techniques have been applied for credit risk assessment. However, to our knowledge, several evaluation techniques are black-box models such as neural networks, SVM, etc. They generate applicants’ classes without any explanation. In this paper, we propose to assess credit risk using rules classification method. Our output is a set of rules which describe and explain the decision. To this end, we will compare seven classification algorithms (JRip, Decision Table, OneR, ZeroR, Fuzzy Rule, PART and Genetic programming (GP)) where the goal is to find the best rules satisfying many criteria: accuracy, sensitivity, and specificity. The obtained results confirm the efficiency of the GP algorithm for German and Australian datasets compared to other rule-based techniques to predict the credit risk.

Keywords: credit risk assessment, classification algorithms, data mining, rule extraction

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Authors: Rahim Ada, Mustafa Harmankaya, Sadiye Ayse Celik

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The safflower seed contains about 25-40% solvent extract and 20-33% fiber. It is well known that dietary phospholipids lower serum cholesterol levels effectively. The nutrient composition of safflower seed changes depending on region, soil and genotypes. This research was made by using of six natural selected (A22, A29, A30, C12, E1, F4, G8, G12, J27) and three commercial (Remzibey, Dincer, Black Sun1) varieties of safflower genotypes. The research was conducted on field conditions for two years (2009 and 2010) in randomized complete block design with three replications in Konya-Turkey ecological conditions. Oil contents, mineral contents and their correlations were determined in the research. According to the results, oil content was ranged from 22.38% to 34.26%, while the minerals were in between the following values: 1469, 04-2068.07 mg kg^-1 for Ca, 7.24-11.71 mg kg^-1 for B, 13.29-17.41 mg kg^-1 for Cu, 51.00-79.35 mg kg^-1 for Fe, 3988-6638.34 mg kg^-1 for K, 1418.61-2306.06 mg kg^-1 for Mg, 11.37-17.76 mg kg^-1 for Mn, 4172.33-7059.58 mg kg^-1 for P and 32.60-59.00 mg kg^-1 for Zn. Correlation analysis that was made separately for the commercial varieties and wild lines showed that high level of oil content was negatively affected by all the investigated minerals except for K and Zn in the commercial varieties.

Keywords: safflower, oil, quality, mineral content

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Authors: Albert Mufundirwa, Satoru Yoshioka, K. Ogi, Takeharu Sugiyama, George F. Harrington, Bretislav Smid, Benjamin Cunning, Kazunari Sasaki, Akari Hayashi, Stephen M. Lyth

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Polymer electrolyte membrane fuel cells (PEMFCs) are electrochemical energy conversion devices used for portable, residential and vehicular applications due to their low emissions, high efficiency, and quick start-up characteristics. However, PEMFCs generally use expensive, Pt-based electrocatalysts as electrode catalysts. Due to the high cost and limited availability of platinum, research and development to either drastically reduce platinum loading, or replace platinum with alternative catalysts is of paramount importance. A combination of high surface area supports and nano-structured active sites is essential for effective operation of catalysts. We synthesize carbon foam supports by thermal decomposition of sodium ethoxide, using a template-free, gram scale, cheap, and scalable pyrolysis method. This carbon foam has a high surface area, highly porous, three-dimensional framework which is ideal for electrochemical applications. These carbon foams can have surface area larger than 2500 m²/g, and electron microscopy reveals that they have micron-scale cells, separated by few-layer graphene-like carbon walls. We applied this carbon foam as a platinum catalyst support, resulting in the improved electrochemical surface area and mass activity for the oxygen reduction reaction (ORR), compared to carbon black. Similarly, silver-decorated carbon foams showed higher activity and efficiency for electrochemical carbon dioxide conversion than silver-decorated carbon black. A promising alternative to Pt-catalysts for the ORR is iron-impregnated nitrogen-doped carbon catalysts (Fe-N-C). Doping carbon with nitrogen alters the chemical structure and modulates the electronic properties, allowing a degree of control over the catalytic properties. We have adapted our synthesis method to produce nitrogen-doped carbon foams with large surface area, using triethanolamine as a nitrogen feedstock, in a novel bottom-up protocol. These foams are then infiltrated with iron acetate (FeAc) and pyrolysed to form Fe-N-C foams. The resulting Fe-N-C foam catalysts have high initial activity (half-wave potential of 0.68 VRHE), comparable to that of commercially available Pt-free catalysts (e.g., NPC-2000, Pajarito Powder) in acid solution. In alkaline solution, the Fe-N-C carbon foam catalysts have a half-wave potential of 0.89 VRHE, which is higher than that of NPC-2000 by almost 10 mVRHE, and far out-performing platinum. However, the durability is still a problem at present. The lessons learned from X-ray absorption spectroscopy (XAS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and electrochemical measurements will be used to carefully design Fe-N-C catalysts for higher performance PEMFCs.

Keywords: carbon-foam, polymer electrolyte membrane fuel cells, platinum, Pt-free, Fe-N-C, ORR

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Authors: Aslı Şalcıoğlu, Grigorous Krey, Raşit Bilgin

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In this study, the effect of the Turkish Straits System (TSS), comprising a biogeographical boundary that forms the connection between the Mediterranean and the Black Sea, on the evolutionary history, phylogeography and intraspecific gene flow of the whiting (Merlangius merlangus) a demersal fish species, was investigated. For these purposes, the mitochondrial DNA (CO1, cyt-b) genes were used. In addition, genetic comparisons samples from other regions (Greece, France, Atlantic) obtained from GenBank and Barcode of Life Database were made to better understand the phylogeographic history of the species at a larger geographic scale. Within this study, high level of genetic differentiation was observed along the Turkish coastal waters based on cyt-b gene, suggesting that TSS is a barrier to dispersal. Two different sub-species were also observed based on mitochondrial DNA, one found in Turkish coastal waters and Greece (M.m euxinus) and other (M.m. merlangus) in Atlantic, France.

Keywords: genetic, phylogeography, TSS, whiting

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Authors: Rachid Belhachemi, Pierre Rostan, Alexandra Rostan

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This paper develops a discrete-time option pricing model for index options. The model consists of two key ingredients. First, daily stock return innovations are driven by a continuous hidden threshold mixed skew-normal (HTSN) distribution which generates conditional non-normality that is needed to fit daily index return. The most important feature of the HTSN is the inclusion of a latent state variable with a continuum of states, unlike the traditional mixture distributions where the state variable is discrete with little number of states. The HTSN distribution belongs to the class of univariate probability distributions where parameters of the distribution capture the dependence between the variable of interest and the continuous latent state variable (the regime). The distribution has an interpretation in terms of a mixture distribution with time-varying mixing probabilities. It has been shown empirically that this distribution outperforms its main competitor, the mixed normal (MN) distribution, in terms of capturing the stylized facts known for stock returns, namely, volatility clustering, leverage effect, skewness, kurtosis and regime dependence. Second, heteroscedasticity in the model is captured by a threeexogenous-factor GARCH model (GARCHX), where the factors are taken from the principal components analysis of various world indices and presents an application to option pricing. The factors of the GARCHX model are extracted from a matrix of world indices applying principal component analysis (PCA). The empirically determined factors are uncorrelated and represent truly different common components driving the returns. Both factors and the eight parameters inherent to the HTSN distribution aim at capturing the impact of the state of the economy on price levels since distribution parameters have economic interpretations in terms of conditional volatilities and correlations of the returns with the hidden continuous state. The PCA identifies statistically independent factors affecting the random evolution of a given pool of assets -in our paper a pool of international stock indices- and sorting them by order of relative importance. The PCA computes a historical cross asset covariance matrix and identifies principal components representing independent factors. In our paper, factors are used to calibrate the HTSN-GARCHX model and are ultimately responsible for the nature of the distribution of random variables being generated. We benchmark our model to the MN-GARCHX model following the same PCA methodology and the standard Black-Scholes model. We show that our model outperforms the benchmark in terms of RMSE in dollar losses for put and call options, which in turn outperforms the analytical Black-Scholes by capturing the stylized facts known for index returns, namely, volatility clustering, leverage effect, skewness, kurtosis and regime dependence.

Keywords: continuous hidden threshold, factor models, GARCHX models, option pricing, risk-premium

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Authors: Neo Mohlabane

Abstract:

-- Feminists across various contexts have written extensively on the subject of ‘Woman.’ Recently the question of difference; to account for the cultural, ethnic, and racial diversity among women themselves has become a highly contested issue in feminist theories. Tensions have ensued where ‘western feminisms’ have been criticized for bias that is embedded in the objectification of ‘different’ women often regarded as ‘other’; traditional, therefore inferior. Thus, it is argued that womanhood; a set of socially defined attributes appropriate for women, holds different meanings depending on the context in which it is defined. Drawing on decolonial feminist approaches, this qualitative study explored the constructions of ‘womanhood’ from the perspective of unmarried Basotho women in Lesotho, where womanhood is predominantly defined in marital terms. Through the narrated life-stories of twenty unmarried Basotho women, the study revealed that as opposed to the ‘traditional’ definition that accounts for a single attribute woman as ‘wife,’ unmarried Basotho women defined ‘womanhood’ in different ways that deconstructed fixed gendered categories. The women drew meaning from their past personal experiences of childhood to construct and re-construct womanhood in adulthood. By transforming their embodied experiences of hardship and sorrow into valuable constructs with which they self-evaluated as resilient and perseverant, the women constructed a base for self-affirmation as woman. In addition, the women anchored their constructions and reconstructions of woman by transforming the meanings attached to the realms of respectability, sexuality and motherhood. Thus, to the question; what is a Woman? In part, the study concluded that there is no such thing as a ‘unitary’ definition of womanhood, instead Mosotho womanhood has always been and will always be in a state of flux; bearing multiplicity and complexity. This study highlights the need to exercise caution when using western concepts to understand the experiences of women in local African contexts. In order to decolonize feminist scholarship, African feminisms need to re-construct conceptual and theoretical frameworks appropriate for analyzing and understanding gender issues in African contexts.

Keywords: decoloniality, feminism, Lesotho, womanhood

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Authors: Ines Gasmi, Salima Smiti, Makram Soui, Khaled Ghedira

Abstract:

Credit risk is considered as one of the important issues for financial institutions. It provokes great losses for banks. To this objective, numerous methods for credit risk evaluation have been proposed. Many evaluation methods are black box models that cannot adequately reveal information hidden in the data. However, several works have focused on building transparent rules-based models. For credit risk assessment, generated rules must be not only highly accurate, but also highly interpretable. In this paper, we aim to build both, an accurate and transparent credit risk evaluation model which proposes a set of classification rules. In fact, we consider the credit risk evaluation as an optimization problem which uses a genetic programming (GP) algorithm, where the goal is to maximize the accuracy of generated rules. We evaluate our proposed approach on the base of German and Australian credit datasets. We compared our finding with some existing works; the result shows that the proposed GP outperforms the other models.

Keywords: credit risk assessment, rule generation, genetic programming, feature selection

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Authors: Xavier Ruiz Del Portal

Abstract:

This paper incorporates mobility between the legal and black economies into a model of tax evasion with endogenous labor supply in which underreporting is possible in one sector but impossible in the other. We have found that the results of the effects along the extensive margin (number of evaders) become more robust and conclusive than those along the intensive margin (hours of illegal work) usually considered by the literature. In particular, it is shown that the following policies reduce the number of evaders: (a) larger and more progressive evasion penalties; (b) higher detection probabilities; (c) an increase in the legal sector wage rate; (d) a decrease in the moonlighting wage rate; (e) higher costs for creating opportunities to evade; (f) lower opportunities to evade, and (g) greater psychological costs of tax evasion. When tax concealment and illegal work also are taken into account, the effects do not vary significantly under the assumptions in Cowell (1985), except for the fact that policies (a) and (b) only hold as regards low- and middle-income groups and policies (e) and (f) as regards high-income groups.

Keywords: income taxation, tax evasion, extensive margin responses, the penalty system

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Authors: Gurleen Kaur

Abstract:

Being tall-short, fat-thin, black-white, etc. is an inevitable part of how people perceive you. This association of people with your external appearance carves out an identity for you. This paper will look at the reasons why people relate a person to a particular categorization on the basis of his/her physical appearance. The paper delves into reasons for this categorization into groups: Subconscious grouping, personal gain, ease of relating to the group, and social acceptance. Development of certain unique physical features also leads to a person relating himself to a collective identity. Thus, this paper will support the fact that physical appearance plays a crucial role in categorization of people into groups and hence forming a group identity for them. This paper is divided into three parts. The first part will discuss what physical appearance is and how is it linked to our daily lives. The second part will talk about why it works i.e. why this factor of external appearance is important in formation of identity. The last part will talk about the factors which lead to categorization of identity because of physical appearance.

Keywords: group identity, physical appearance, subconscious grouping, collective identity

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Authors: Tsediso Makoelle

Abstract:

South Africa like in other parts of the world has acknowledged the prevalence of the phenomenon of homosexuality in the society. Due to the number of homosexuality cases in the South African society, questions have been asked about the impact of homosexuality in schools and how teachers and learners deal with homosexuality within the context of an emerging inclusive education system. This qualitative study analysis the experiences of teachers and learners in selected secondary schools in relation to prevalence of transgender in schools. Interviews were conducted with principals, teachers and focus group of learners in schools were cases homosexuality have been reported. Data was analysed using an inductive analysis framework. Among the findings was that homosexuality is still viewed as a taboo in Black-African dominated school communities and that the need to create all-embracing and inclusive environment was evident. The study suggests a needs to open communications in communities about homosexuality in order to develop an all-inclusive environment for all learners regardless of their sexual orientation.

Keywords: homosexuality, inclusive education, sexual orientation, transgender

Procedia PDF Downloads 246