Forchheimer Model for Non-Darcy Flow in Porous Media and Fractures

Imperial Users onl

The Impact of Heterogeneity on Tertiary Miscible Gas Injection

Imperial Users onl

Shadow of a Charged Rotating Black Hole in f(R)f(R) Gravity

We study the shadow of a charged rotating black hole in $f(R)$ gravity. This black hole is characterized by mass, $M$, spin, $a$, electric charge, $Q$ and $R_{0}$ which is proportional to cosmological constant. We analyze the image of the black hole's shadow in four types 1) at $r\rightarrow\infty$, 2) at $r\rightarrow r_{o}$, in vacuum, 3) at $r\rightarrow\infty$, 4) at $r\rightarrow r_{o}$, for an observer at the presence of plasma. Moreover, we investigate the effect of spin, charge and modfication of gravity on the shape of shadow. In addition, we use two observables, the radius $R_{s}$ and the distortion parameter $\delta_{s}$, characterizing the apparent shape. We show that for all cases, the shadow becomes smaller with increasing electric charge. Also, by increasing the rotation parameters, circular symmetry of the image of black hole's shadow will change. Furthermore, in the presence of plasma, plasma parameter also effects on size of the shadow.Comment: 28 pages,6 tables,43 figure

Biden's Challenge: Kurdish Autonomy and Turkish Expansionism

The United States wants to end "forever wars" in the Middle East, among them the war against ISIS in Syria and Iraq. Much to Turkey's dismay, Kurdish forces were crucial on-the-ground allies in that pursuit. While the military battle is subsiding, the question has arisen of how the new US administration will politically approach its Kurdish allies and deal with Turkey's expansionism in the future. Turkish expansionism worries the European Union and United States, despite it having been facilitated by them in the past: Both entities allowed Turkish president Erdoğan to expand militarily into Kurdish areas in Syria and Iraq without any political repercussions from his Western allies. Therefore, a currently untamed and unilaterally acting Turkey will be one of Biden's greatest challenges in the region. Biden will campaign for an end to endless wars, as Trump did, but he also knows that an abrupt withdrawal of US forces is not a solution. Rather, a comprehensive post-war structure for Syria must be drafted, in which the Syrian Democratic Forces should play a crucial role. The main obstacle to such an encompassing agreement will be Turkey. The Kurdistan Region of Iraq represents a historical precedent that should not be copied. Since 2016, Turkey has increasingly and repeatedly targeted civilians there, even though the region's Kurdish administration formally cooperates with Turkey. The short-sighted approach that the United States took vis-à-vis the Iraqi Kurds - only granting them autonomy if they agree to act as a proxy force for Turkey - has enabled this. Joe Biden as well as his secretaries of state and of defense, respectively Antony Blinken and Lloyd Austin, have much experience on the Kurdish question and, to some extent, strong pro-Kurdish records. They will likely push for a compromise between Kurdish actors and Turkey in the time to come. To achieve long-lasting stability concerning the Kurdish question, Biden's administration should design policies that aim to prevent Turkish unilateralism and facilitate peace talks between Ankara and especially the PKK leadership, in cooperation with partners in the European Union. Furthermore, the political recognition of the Kurds in Syria is central to defending the gains made against ISIS

The Kurds defeated Islamic State - now Turkey wants to end their success story

We owe much to the Kurds for the defeat of Islamic State, even if the fight still goes on. Yet, writes the author, the rise of Turkey as an unpredictable military power threatens post-conflict reconstruction - and Syria's democratic future

Analysis of Sustainable Transport for Smart Cities

For decades, transportation has been considered as a link to all aspects of life worldwide. In this case, the world's natural environment, social well-being and economic development all usually depend on transportation systems. In most cases, safe, clean, sustainable and equitable transport systems help countries, especially in cities and urban centers, to thrive. However, a wide range of research shows that transportation systems in most of the cities and urban areas are unsustainable. In fact, some of these transportation systems are considered to be a threat to the environmental, social and economical aspects of future generations. In this perspective, therefore, changing such trends in transportation requires the collaboration of various stakeholders at regional, national and international levels. In this paper, therefore, a wide range of definitions of sustainable transport are discussed. More so, some of the aspects of smart transport for modern cities such as cycling and the role of women in sustainable transport were explored. With the aim of getting to the core of the subject, cases of women in bicycle transport, especially in the Netherlands and Germany compared to Kenya and Uganda are equally elucidated. Although not fully outlined, the idea of smart cities and sustainable transport have heterogeneous characteristics globally as discussed herein.O

An Analysis of Social Ties: Coffee Value Chain in Uganda

Uganda is among the worlds' largest coffee producers and exporters. Coffee production in Uganda has been a developing process over the last 60 years, with various players from the garden, home drying, factories, stores and exporters, and lastly at tables. This study investigates the nature and the different types of ties used for coffee development in Uganda. These ties form what is referred to as value chain which herein has been very paramount in the production and trade of coffee in Uganda. The study consisted of both qualitative and quantitative studies to find out the relationships existing between the different types of ties used in the coffee processes. The research used mutually regression and correlation approaches to analyze field data collected from the coffee farmer families, buyers and the regulators in Uganda. The findings illustrate a statistically significant relationship between family ties and coffee development, farm and firm ties, friendship ties and coffee development. The results established that weak ties are more beneficial than strong ties bearing in mind the development of coffee farming and production than the strong ties in Uganda. Further research needs to be directed on these networks in the coffee value chain, and appropriate solutions for its competitiveness and sector growth. Understanding connections which our study referred to as ties is very vital for the success of any business of sorts.O

Impact and flexural properties of hybrid jute/HTPET fibre reinforced epoxy composites

In this study, hybridizing jute with high tenacity polyethylene terephthalate (HTPET) fibres has been proposed. Different hybrid jute/HTPET fibre reinforced epoxy composite samples have been fabricated with different weight ratios of HTPET, and subjected to charpy impact and three-point bending test. The results show that increasing the content of HTPET fibres in the composites will considerably improve their energy absorption capabilities and structural integrity after impact and bending test. However, hybrid composites with HTPET show lower flexural stress and bending modulus than pure jute composites

The Educational Needs of the Patients who Take Treatment in Psychiatric Clinic in Kars

AbstractThis study was done with the aim of to determine the educational needs of the patients who take treatment in psychiatric clinic in Kars. The study which is a cross-sectional was made in Kars Government Hospital's Psychiatric Clinic with 50 patients, between 02.01.2012 - 30.04.2012. In collecting data, a questionnaire and the Educational Needs Questionnaire (EDQ) were used. The participants who takes place in the survey, the patients includes who have depression diagnosis are (40%) and men (66%). When we look to the points mean average that they get from the EDQ is 29.04 ± 5.59. According to the EDQ: the 3 articles which they get the highest marks in order are: “Anger, violence, assaultive behaviour”, “Sleeping problems”, “Problems with concentration” and “Patients self-help organizations”. Educational Needs, it was seen that; the ones who has nuclear family, who has social guarantee, who applies to non-medical people, who has social supporters from their family, who lose their job because of mental illness, who has a belief that they will be get well, have a higher point of mean average. According to these results, it is supposed that the educational programs must be planned due to the fact that the patients have needs for information and when doing this the needs of the patients must be remembered