Suchergebnisse

Hikama (Governance) is a peer reviewed academic journal published by the Arab Center for Research and Policy Studies and Doha Institute for Graduate Studies (p-ISSN: 2708-5805), (e-ISSN: 2708-5813). Hikama seeks to broaden the understanding of the fields of public policy and public administration in the Arab World and reinvigorate the political and social elements of public policy. It is a space for academic thought and discussion on what Arab governments - with their values, institutions, and public bodies - are doing, and should aspire to do in order to nurture politically modern and socially just Arab societies. -- AHMED MOHSEN Doctoral candidate, Faculty of Political Science and International Relations, Sabahattin Zaim University, Turkey. Email: abdelrahman.ahmed@std.izu.edu.tr ; تحاول هذه الدراللسة الإجابة عن اللسؤال التالي: لماذا اختلفت الستجابة الأجهزة البيروقراطية والتنفيذية عند تصميم اللسياسات الصحية وتنفيذها تجاه أزمة جائحة فيرولس كورونا المستجد (كوفيد19) في دول تبدو متشابهة، كونها تملك ميراثا من المركزية والأنظمة الرئالسية، كما همي الحال في مصر وتركيا؟ وتنطلق فرضية الدراسة الرئيسة من أن الأزمة في بدايتها أعطت ملساحة أكبل للوزراء التنفيذيين والتكنوقراط والأجهزة البيروقراطية المتخصطة فمي اللسيالسات الطحية والوبائية للمساهمة بشكل أكبر فمي 'لاكلملم اللسياسات الطحية لمواجهة هذا الوباء، لكن الستمرار هذه الملساحة والستكمال تلك الأدوار ارتبط بعد ذلك بمدم توافر "القدرة السياساتية" التي تتيح لهؤلاء المسؤولين ذلك. تظهر الدراسة من خلال دراسة الحالة التركية والمصرية بصورة مقارنة، أنه كلما كانت الدولة أكثل مركزية، وكانت للأزمة التمي تواجهها طبيعة خاطة وغير مسبوقة، ولديها فمي الوقت نفسه قدرات سياساتية أعلل فمي تصميم السياسات، فإن هذا يساهم فمي تعزيز دور الخبراء والبيروقراطيين في تطميم اللسيالسات عل حلساب اللسيالسيين. ; This paper seeks to answer the following question: Why have the bureaucracies and executive arms of two highly centralized presidential regimes – Egypt and Turkey – produced such different responses to the Coronavirus crisis? Its basic hypothesis is that while the crisis did initially provide scope for ministers, technocrats and bureaucrats specialized in public health to play a greater part in making health policy, their ability to maintain this newfound influence depended on their "policy capability". Through a comparison of the two case studies, this article shows that the more centralized a state is, the more unprecedented the crisis is and the more policy capability it has, the greater the role bureaucrats play at the expense of politicians.

AbstractDespite the substantial impact of rivers on the global marine litter problem, riverine litter has been accorded inadequate consideration. Therefore, our objective was to detect riverine litter by utilizing middle-scale multispectral satellite images and machine learning (ML), with the Tisza River (Hungary) as a study area. The Very High Resolution (VHR) images obtained from the Google Earth database were employed to recognize some riverine litter spots (a blend of anthropogenic and natural substances). These litter spots served as the basis for training and validating five supervised machine-learning algorithms based on Sentinel-2 images [Artificial Neural Network (ANN), Support Vector Classifier (SVC), Random Forest (RF), Naïve Bays (NB) and Decision Tree (DT)]. To evaluate the generalization capability of the developed models, they were tested on larger unseen data under varying hydrological conditions and with different litter sizes. Besides the best-performing model was used to investigate the spatio-temporal variations of riverine litter in the Middel Tisza. According to the results, almost all the developed models showed favorable metrics based on the validation dataset (e.g., F1-score; SVC: 0.94, ANN: 0.93, RF: 0.91, DT: 0.90, and NB: 0.83); however, during the testing process, they showed medium (e.g., F1-score; RF:0.69, SVC: 0.62; ANN: 0.62) to poor performance (e.g., F1-score; NB: 0.48; DT: 0.45). The capability of all models to detect litter was bounded to the pixel size of the Sentinel-2 images. Based on the spatio-temporal investigation, hydraulic structures (e.g., Kisköre Dam) are the greatest litter accumulation spots. Although the highest transport rate of litter occurs during floods, the largest litter spot area upstream of the Kisköre Dam was observed at low stages in summer. This study represents a preliminary step in the automatic detection of riverine litter; therefore, additional research incorporating a larger dataset with more representative small litter spots, as well as finer spatial resolution images is necessary.

The aims of this paper is investigating the spread of AIDS both within-host, through the contact between healthy cells with free virus inside the body, and between-host, through sexual contact among individuals and external sources of infectious. The outbreak of AIDS is described by a mathematical model consisting of two stages. The first stage describes the within-host spread of AIDS and is represented by the first three equations. While the second stage describes the between-host spread of AIDS and represented by the last four equations. The existence, uniqueness and boundedness of the solution of the model are discussed and all possible equilibrium points are determined. The local asymptotic stability (LAS) of the model is studied, while suitable Lyapunov functions are used to investigate the global asymptotic stability (GAS) of the model. Optimal control strategy is used to control the outbreak of AIDS. Finally, a numerical simulation is carried out to confirm the analytical results and understand the effects of varying the parameters on the spread of disease.

‎ Since the first outbreak in Wuhan, China, in December 31, 2019, COVID-19 pandemic ‎has been spreading to many countries in the world. The ongoing COVID-19 pandemic has caused a ‎major global crisis, with 554,767 total confirmed cases, 484,570 total recovered cases, and ‎‎12,306 deaths in Iraq as of February 2, 2020. In the absence of any effective therapeutics or drugs ‎and with an unknown epidemiological life cycle, predictive mathematical models can aid in ‎the understanding of both control and management of coronavirus disease. Among the important ‎factors that helped the rapid spread of the epidemic are immigration, travelers, foreign workers, and foreign students. In this work, we develop a mathematical model to study the dynamical ‎behavior of COVID-19 pandemic, involving immigrants' effects with the possibility of re-infection. ‎Firstly, we studied the positivity and roundedness of the solution of the proposed model. The stability ‎results of the model at the disease-free equilibrium point were presented when . Further, it was proven that the pandemic equilibrium point will persist uniformly when . Moreover, we ‎confirmed the occurrence of the local bifurcation (saddle-node, pitchfork, and transcritical). Finally, ‎theoretical analysis and numerical results were shown to be consistent.