13 research outputs found

    ADHOCTCP: Improving TCP Performance in Ad Hoc Networks

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    The Role of Iran Regarding the U.S. Security Systems in the Persian Gulf Region

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    Since the withdrawal of U.K from the east of Suez and the Persian Gulf region, the security system of this area has been confronted with many challenges and the concern about security has been reintroduced in to the debate on the world order and it has enhanced the previous efforts of the united states of America to establish a balance of power security system among Soviet Union. Furthermore, the end of formal domination of United Kingdom since 1971 brought to the debate the issue of security studies and related questions in the Persian Gulf region. Occurrence of the Islamic revolution in Iran in 1979 was a period that the U.S. interests in the Persian Gulf confronted with serious challenges and so the U.S. leaders began to make some important policies for this region; because this area had an important role for America's economy and industries. But these policies have always been facing serious challenges from Iran and other countries in the region. This article is to study perspective of the U.S. government on security systems of the United States in the Persian Gulf region and internal security approaches according on specific characteristics of this region taken by the littoral stats based on indigenous values and practices. Key words: Regional security; Persian Gulf; United States; Dual containment; Twin pillar policy; Carter DoctrineResumé: Depuis le retrait du Royaume-Uni dans l'est de Suez et dans le golfe persique, le système de sécurité de cette région a été confrontée à de nombreux défis et la préoccupation concernant la sécurité a été réintroduite dans le débat sur l'ordre mondial. Il a renforcé les efforts précédents des États-Unis de créer un équilibre du système de sécurité de pouvoir au sein de l'Union soviétique. En outre, la fin de la domination formelle du Royaume-Uni depuis 1971 a apporté au débat la question des études de sécurité et des questions apparentées dans la région du golfe persique. Le surgissement de la révolution islamique en Iran en 1979 était une période dans laquelle les intérêts américains dans le golfe persique sont confrontés à des défis sérieux et donc les dirigeants américains ont commencé à faire des politiques importantes pour cette région, parce que cette région a un rôle important pour l'économie et industries américaines. Mais ces politiques ont toujours été confrontés à des défis sérieux de l'Iran et des autres pays dans la région. Cet article tente d'étudier la perspective du gouvernement américain sur les systèmes de sécurité des États-Unis dans la région du golfe persique et les approches de la sécurité intérieure en fonction des caractéristiques spécifiques de cette région des états littoraux basées sur des valeurs et des pratiques autochtones.Mots-clés: sécurité régionale; Golfe Persique; Etats-Unis; double confinement; politique de deux piliers; Doctrine Carte

    Development of Hybrid Adaptive Neuro Fuzzy Inference System - Harris Hawks Optimizer (ANFIS-HHO) for Monthly Inlet Flow to Dam Reservoirs Prediction

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    Nowadays, machine learning models are able to make good predictions based on pattern extraction between data. In this study, a neural-fuzzy network (ANFIS) was used to predict the inflow to the reservoirs of a dam namely, the Mahabad dam located in the northwestern part of Iran. A new Harris Hawk (HHO) optimization algorithm was also used to improve the ANFIS (HHO-ANFIS) structure. Monthly precipitation and temperature and inlet flow data to the reservoir one to three months ago were used as input parameters as 6 different input patterns. About 70% of the data was used for training and 30% to test the models. The results showed that the ANFIS model has good accuracy in training data although, for test data, its accuracy was greatly reduced. The development of the HHO-ANFIS model improved the accuracy of the prediction. The patterns with all input parameters had the highest prediction accuracy. In this pattern, values ​​of Root Mean Square Error (RMSE), Mean Absolute Error (MAE), and Nash Sutcliffe Efficiency coefficient (NSE) for test data were 3.9 MCM, 2.41 MCM, and 0.86, respectively. Due to the good performance of the model used, it can be recommended for time series predictions

    First evidence of the presence of adenovirus type 8 in myocardium of patients with severe idiopathic dilated cardiomyopathy

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    Previous studies have detected adenovirus and cytomegalovirus (CMV) in cardiac tissue of patients with myocarditis. Therefore, in this study, we investigated the frequency of these viruses, which may be involved in the development of severe dilated cardiomyopathy (DCM). Myocardial tissue from of 23 cardiac transplant candidates with acute idiopathic DCM below the age of 40 years were analyzed by amplification of adenovirus and CMV DNA and subsequent sequencing. Adenovirus was detected in four (17.4%) and CMV in one (4.3%) of the patients. All controls were negative for the presence of both viruses. Our study shows that myocardial infection with adenovirus may play an important role in the pathogenesis of severe DCM and suggests that vaccination against adenovirus might be helpful in decreasing the prevalence of severe idiopathic DCM. This is the first study in which adenovirus type 8 has been detected in the hearts of patients with DCM

    U.S. policies toward Iran and implications for regional security in the Persian Gulf 1979-2008

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    This research examined the US policies toward Iran and its implications on regional security in the Persian Gulf during the period from 1979 – 2008. In addition, the study also evaluated the U.S. policies toward Iran in relations to the Persian Gulf during the presidencies of Carter, Reagan, George HW Bush, Clinton, and George Bush during this period of time. The objectives of the research were achieved by seeking answers to the two research questions: 1) What were the evolutions of the U.S. regional security policies regarding Iran in the Persian Gulf from 1979 to 2008?; 2) What were the influences of the U.S. regional security policies on the regional peace and stability regarding Iran in the Persian Gulf? Based on the research questions, the goals of this study were to examine and analyze the security policies of different US administrations from the time of the Islamic revolution in 1979 until the end of the George W. Bush presidency in 2008. In other words, the main focus of the study was to understand the security policies of the US administrations during the period from 1979 to 2008 toward Iran in the Persian Gulf region. Therefore, the study attempted to evaluate these security policies to identify and explain the factors of success or failure of these policies in the Persian Gulf region and to finally determine the security status of the Persian Gulf. As such, evaluating the thrust of various US policies toward Iran in the Persian Gulf region will show the success or failure of the US to create peace and security in the region. For this purpose, the qualitative approach was selected and applied to the study and the data were collected from official websites available on the internet. Such data comprised the speeches of the Iranian and American administrations, official records and documents on security policies of the US toward Iran in the Persian Gulf region including the Arms Export Control Act, U.S. Congress negotiations, US Department of State annual reports, Country Reports on Terrorism, Peterson Institute Documents, and Middle East policy council documents. Thus, the goal of using the qualitative approach was to obtain an in-depth understanding of the security policies of the US toward Iran in the Persian Gulf region during the specified period. The analysis of the data revealed that the unilateral security policies of different US administrations toward Iran in the Persian Gulf did not succeed in establishing stability and peace for the region. Based on the conclusions of the research, the three main findings are outlined as follows: Firstly, the findings of the current study about the U.S. policies toward Iran in relation to the Persian Gulf region since the Islamic Revolution of Iran in 1979 show that these policies were always confronted by challenges from local states such as Iran and Iraq and in some cases, a few regional conservative Arab states such as Saudi Arabia. This implies the failure of the unilateral U.S. security policies in the Persian Gulf region. Secondly, the analysis of the ―Regional Security Complex Theory‖ proves that according to the ―Regional Security Complex Theory‖, there were significant relationships between the rivalries of the regional states in the Persian Gulf and external interventions. The results revealed that local rivalries led to the interference by external powers in the region. In the case of Iran, the rivalries inside the Gulf Cooperation Council states and between them and Iran and Iraq led to U.S. intervention in the region. Moreover, the results obtained from application of the theory to the realities of the region revealed that the only reasonable solution for the security problems of the Persian gulf region is a collective security forum that involves all the states of this important area including the GCC states, Iran and Iraq (6+2 arrangement). Finally, the findings of this study have important implications for the promotion of peace and security in the Persian Gulf region. As the results showed, the various direct and indirect U.S policies toward Iran related to the Persian Gulf were unable to enhance American demands for a stable condition to maintain their interest in the region. Furthermore, the U.S. policies could not stop Iran‘s ambitions to have a collective security policy that involved all the Persian Gulf states in a forum. So the findings of this study suggest that to stabilize the region, there should be multilateral relations between Iran, Iraq, the GCC and U.S. that consider the concerns of all parties and the participation of all local states for peace and security to be achievable in the region

    Anterior Spinal Artery Syndrome Following Coronary Artery Bypass Grafting: a Case Report Abbreviations, acronyms & symbols CABG CPB CT IABP MRI = Coronary artery bypass grafting = Cardiopulmonary bypass = Computed tomography = Intra-aortic balloon pump =

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    Abstract We present a patient with unstable angina candidate for coronary artery bypass grafting. Saphenous vein graft was used in obtuse marginal and left internal mammary artery to left anterior descending artery properly. After surgery, the patient experienced flaccid paralysis of lower limb and impaired sensation of touch and warmth of knee and below. A computed tomography angiogram of lower limbs and thoracolumbar magnetic resonance imaging showed no abnormality. Based on the symptom, clinical diagnosis of anterior spinal artery syndrome was considered. The artery of Adamkiewicz is an important supplier to the anterior spinal artery. Internal thoracic mammary artery, used in coronary artery bypass grafting, is suspected as a collateral supplier of the artery of Adamkiewicz and has been accused for cause of spinal infarction

    Investigating and Modeling of the Scour Downstream of a Tree Trunk Deflector in a Straight Channel

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    Scouring depends on several factors, including the water flow of artificial obstacles, sections, piers, and foundations, the disturbance of bed materials, and soil permeability. The other factors are the non-parallelism between piers and the water flow, the type of river activity (static or dynamic), and the existence of a waterfall or an obstacle that forms a waterfall in natural bed materials, causing the underlying bed materials to be washed away. This study fully investigated how the movement of a tree trunk affects a river’s flow by considering different flow conditions using the artificial neural network (ANN) model. A feedforward optimal network with the error back-propagation training algorithm and sigmoid transfer functions was used for four models. To determine the number of neurons in the hidden layer, one and ten neurons were selected in the hidden layer according to verification indicators. In addition, a physical model was utilized to measure data. To verify and test the models, our data were gathered in a laboratory using the physical model. Considering the network structure of one neuron in the hidden layer, a comparison was made between dimensional and dimensionless parameter models that are effective in terms of the dimensions of the scour hole. The comparison between the results of the ANN and the measured data using nonlinear regression models demonstrated that the ANN was more accurate and capable of simulating phenomena. Additionally, R and RMSE values were between 0.93 and 0.98, as well as 0.18 and 0.013, respectively. Finally, the results related to the width, height, length, and depth of the scour revealed that the modified DOT model had the best agreement with Mahdavizadeh’s measured data

    Anterior Spinal Artery Syndrome Following Coronary Artery Bypass Grafting: a Case Report

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    Abstract We present a patient with unstable angina candidate for coronary artery bypass grafting. Saphenous vein graft was used in obtuse marginal and left internal mammary artery to left anterior descending artery properly. After surgery, the patient experienced flaccid paralysis of lower limb and impaired sensation of touch and warmth of knee and below. A computed tomography angiogram of lower limbs and thoracolumbar magnetic resonance imaging showed no abnormality. Based on the symptom, clinical diagnosis of anterior spinal artery syndrome was considered. The artery of Adamkiewicz is an important supplier to the anterior spinal artery. Internal thoracic mammary artery, used in coronary artery bypass grafting, is suspected as a collateral supplier of the artery of Adamkiewicz and has been accused for cause of spinal infarction

    Comparative Study of the Effect of Indomethacin and Acetaminophen on Pain after Collagen Cross-Linking Surgery

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    Introduction: One of the surgeries that needs to be considered after pain and discomfort is corneal cross-linking of the cornea. The aim of this study was to compare the effect of indomethacin and acetaminophen oral surgery before surgery on postoperative pain in the patients undergoing collagen cross-linking surgery. Methods: The present study was a double-blind clinical trial study that was performed on all the patients undergoing collagen cross-linking surgery. Fifty patients were divided into two groups of 25 patients receiving acetaminophen 500 mg and indomethacin 75 mg before surgery. VAS scale was used to determine the severity of pain. Data were collected through a pain questionnaire and statistically analyzed using SPSS16 software. Results: In the acetaminophen group, 60% were female and 40% male, and in the indomethacin group, 64% were female and 36% male, which were similar in terms of gender. The mean age in the acetaminophen group was 24.28±5 and in the indomethacin group was 24.04±4. The two groups were similar in the case of age. Based on Visual Analogue Scale (VAS) after collagen cross-linking surgery, the pain intensity was 6.29 in the acetaminophen group and 7.61 in the indomethacin group, respectively, which was significantly lower in the acetaminophen group. Moreover, there was no significant difference between the amounts of postoperative pain in the two groups. Conclusion: Oral administration of acetaminophen before corneal cross-linking surgery was more effective in reducing postoperative pain than indomethacin, while there was no difference in the number of postoperative analgesics between the two groups during 24 hours postoperation

    Traveling wave solution by differential transformation method and reduced differential transformation method

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    The present study further examines two recent semi-analytic methods, a reduced order of nonlinear differential transformation method (also called RDTM) and differential transformation method along with Pade approximation to discuss Jaulent–Miodek and coupled Whitham–Broer–Kaup equations. The basic ideas of these methods are briefly introduced and performance of the proposed methods for above mentioned equations is evaluated via comparing with exact solution. The results illustrate that the so-called DTM method, unlike RDTM, due to the presence of secular terms (similar to perturbation method), cannot be found practical for nonlinear partial differential equations (particularly in Acoustic and Wave propagation problems) even through utilizing Pade approximation; meanwhile, RDTM method, despite its simplicity and rapid convergence, assured a significant accuracy and great agreement, and thus it is fair to say that nonlinear problems together with Acoustic application which cannot be solved via Analytical methods, can be studied with reduced order of nonlinear differential transformation method
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