Direct perturbations of aggregate excess demand

We establish that an exchange economy, i.e., preferences and endowments, that generates a giiven aggregate excess demand (AED) function is close to the economy generating the AED obtained by an arbitrary perturbation of the original one.Arrow-Debreu, transversality, exchange economy.

EDUCATIVE NETWORK’S ROLE IN REINFORCING THE ACADEMIC DEVELOPMENT IN THE PALESTINIAN UNIVERSITIES (REFLECTIVE MODEL TOWARD AND INNOVATION IN TEACHING AND LEARNING)

The need for an educational proposal to emerge in the Palestinianeducational context is necessary and needed to face the various challenges that the higher education is dealing with in Palestine. The centers for teaching and learning (CTEs) in the Palestinian universities should be seen as part of the effort to support the evolving process and the innovation needed to allow these higher education institutions be able to compete on local, regional and international level.Methods. It is an approach to a contextualized education, with a significant role played by all who connects and interacts with the community environment and society needs, in order to build an educative community projects. This needs a real educative action with engagement and commitment by all role actors and stakeholders.Results and scientific novelty. Based on personal experience I would like to transmit what I have learned and gained in my teaching and learning experiences and present an educative proposal that is based on the connection between the different educative higher institutions in Palestine. This proposal tackles social and educational challenges through a common process; it is about adapting a concrete model of Educative network in Palestine. The proposal is presenting itself as an alternative model to help the higher education to be more integrated to the society needs and to obtain the coordina tion role for innovative actions in a comprehensive way to fulfill the educational vision of being a leading body in the evolving society in conflict. Practical significance. The purpose of this article is to offer a very practical reflective model that becomes a guidance to sustain CTEs activities and engage more faculties to positively change the learning/teaching culture of their universities. It is about how networks can help to bring about change to education in the Palestinian Universities. I believe that university policymakers and CTEs all alike will find the reasons why educative networks are fast becoming the learning reform organizations.Цель статьи – показать возможности сетевой модели деятельности университетов, адаптированной к специфике образовательного пространства Палестины. Такая модель позволит, по мнению автора, преодолеть различные проблемы, с которыми сталкивается палестинская высшая школа, изыскать дополнительные ресурсы для ее развития, позитивно изменить процесс обучения и культуру преподавания в университетах. Методы и методология. Исследование опирается на контекстуальный подход к организации высшего образования. Результаты и научная новизна. Описана альтернативная традиционному обучению сетевая модель высшего палестинского образования. Доказывается, что для ее реализации необходимо создание центров преподавания и обучения (ЦПО) в высших учебных заведениях. Предназначение таких организаций, осуществляющих работу по сетевому принципу, состоит в поддержке инновационных процессов в высшей школе, повышении ее конкурентоспособности на местном, региональном и международном уровнях через привлечение к решению социальных и образовательных задач как можно большего числа способных и высококвалифицированных профессионалов. Автор, исходя из личного опыта преподавательской и организаторской работы в сетевом поле, объединяющем различные вузы Палестины, полагает, что благодаря сетевому сотрудничеству ЦПО способны стать локомотивом проведения эффективных реформ в образовательной сфере на территории государства. Подобные центры могут исполнять координационную роль в создании и претворении в реальность общественно-образовательных проектов с участием всех заинтересованных сторон и комплексным учетом потребностей общества, развивающегося в условиях конфликта. Практическая значимость. Внедрение в практику высшего образования предлагаемой в публикации модели поможет добиться качественных перемен в деятельности палестинских университетов, сделать высшую школу более интегрированной в социальные и экономические процессы в государстве

On the Sum of Fisher-Snedecor F Variates and its Application to Maximal-Ratio Combining

Capitalizing on the recently proposed Fisher-Snedecor F composite fading model, in this letter, we investigate the sum of independent but not identically distributed (i.n.i.d.) Fisher-Snedecor F variates. First, a novel closed-form expression is derived for the moment generating function of the instantaneous signal-to-noise ratio. Based on this, the corresponding probability density function and cumulative distribution function of the sum of i.n.i.d. Fisher- Snedecor F variates are derived, which are subsequently employed in the analysis of multiple branch maximal-ratio combining (MRC). Specifically, we investigate the impact of multipath and shadowed fading on the outage probability and outage capacity of MRC based receivers. In addition, we derive exact closed-form expressions for the average bit error rate of coherent binary modulation schemes followed by an asymptotic analysis which provides further insights into the effect of the system parameters on the overall performance. Importantly, it is shown that the effect of multipath fading on the system performance is more pronounced than that of shadowing.Comment: 5 pages, 3 figure

A Cloud Platform-as-a-Service for Multimedia Conferencing Service Provisioning

Multimedia conferencing is the real-time exchange of multimedia content between multiple parties. It is the basis of a wide range of applications (e.g., multimedia multiplayer game). Cloud-based provisioning of the conferencing services on which these applications rely will bring benefits, such as easy service provisioning and elastic scalability. However, it remains a big challenge. This paper proposes a PaaS for conferencing service provisioning. The proposed PaaS is based on a business model from the state of the art. It relies on conferencing IaaSs that, instead of VMs, offer conferencing substrates (e.g., dial-in signaling, video mixer and audio mixer). The PaaS enables composition of new conferences from substrates on the fly. This has been prototyped in this paper and, in order to evaluate it, a conferencing IaaS is also implemented. Performance measurements are also made.Comment: 6 pages, 6 figures, IEEE ISCC 201

Cosmological Aspects of Rolling Tachyon

We examine the possibility of rolling tachyon to play the dual roll of inflaton at early epochs and dark matter at late times. We argue that enough inflation can be generated with the rolling tachyon either by invoking the large number of branes or brane world assisted inflation. However, reheating is problematic in this model.Comment: RevTeX 4 pages, Talk delivered in PASCOS held at TIFR (Mumbai) from 3rd Jan to 9th Jan. To appear in the proceedings of PASCOS to be published in a special issue of Praman

Nuclear classical dynamics of H2_2 in intense laser field

In the first part of this paper, the different distinguishable pathways and regions of the single and sequential double ionization are determined and discussed. It is shown that there are two distinguishable pathways for the single ionization and four distinct pathways for the sequential double ionization. It is also shown that there are two and three different regions of space which are related to the single and double ionization respectively. In the second part of the paper, the time dependent Schr\"{o}dinger and Newton equations are solved simultaneously for the electrons and the nuclei of H$_2$ respectively. The electrons and nuclei dynamics are separated on the base of the adiabatic approximation. The soft-core potential is used to model the electrostatic interaction between the electrons and the nuclei. A variety of wavelengths (390 nm, 532 nm and 780 nm) and intensities ($5\times10^{14}$ $Wcm^{-2}$ and $5\times10^{15}$ $Wcm^{-2}$) of the ultrashort intense laser pulses with a sinus second order envelope function are used. The behaviour of the time dependent classical nuclear dynamics in the absence and present of the laser field are investigated and compared. In the absence of the laser field, there are three distinct sections for the nuclear dynamics on the electronic ground state energy curve. The bond hardening phenomenon does not appear in this classical nuclear dynamics simulation.Comment: 16 pages, 7 figure

Non-small cell lung cancer: disease spectrum and management in a tertiary care hospital

Objectives: To review the spectrum of presentation and the surgical management of Non Small Cell Lung Cancer (NSCLC) and the role of various diagnostic modalities in predicting the post-operative stage and the correlation of the post-operative stage with the chances of recurrence.SETTINGS: The Aga Khan University Hospital, Karachi--a tertiary care referral center in Paksitan.Methods: This is a retrospective study of medical records of all the patients who were managed at the Aga Khan University Hospital (AKUH) between 1988 and 1998. The patients with a diagnosis of lung cancer were identified using the ICD-9-CM coding system and the data was analyzed for patients with NSCLC only.Results: A total of 773 patients were admitted with a diagnosis of lung cancer at AKUH over 10 years period. Out of these 21 (2.71%) underwent staging mediastinoscopy and 20 (2.58%) patients underwent exploratory thoracotomy and biopsy without any resection, as the disease was found to be unresectable. Only 18 (2.32%) patients underwent surgical resection. There were 15 males and 3 females and the mean age was 53 years. Mean duration of symptoms was 12 months and cough and haemoptysis were the main presenting symptoms. Most of the tumors were located on the right side. CT scan and mediastinoscopy were mainly used to stage the disease. Complete surgical resection including en-bloc resection of adjacent structures was attempted, when possible. Median follow up was 24 months and the recurrence rate was 39%. There was no significant correlation between post-op stage and recurrence.CONCLUSION: It is concluded that most of the patients present at the advanced stage and resection is possible only in a small number of patients. The size of primary tumor and local extension should not contra-indicate surgery in patients with negative mediastinal nodes and without distant metastasis as it can be performed safely. All pulmonary lesion in the adults must be thoroughly investigated as early diagnosis and complete resection is the only key to cure and long term survival

Fuzzy Integral Based Multi-Sensor Fusion for Arc Detection in the Pantograph-Catenary System

The pantograph-catenary subsystem is a fundamental component of a railway train since it provides the traction electrical power. A bad operating condition or, even worse, a failure can disrupt the railway traffic creating economic damages and, in some cases, serious accidents. Therefore, the correct operation of such subsystems should be ensured in order to have an economically efficient, reliable and safe transportation system. In this study, a new arc detection method was proposed and is based on features from the current and voltage signals collected by the pantograph. A tool named mathematical morphology is applied to voltage and current signals to emphasize the effect of the arc, before applying the fast Fourier transform to obtain the power spectrum. Afterwards, three support vector machine-based classifiers are trained separately to detect the arcs, and a fuzzy integral technique is used to synthesize the results obtained by the individual classifiers, therefore implementing a classifier fusion technique. The experimental results show that the proposed approach is effective for the detection of arcs, and the fusion of classifier has a higher detection accuracy than any individual classifier

Delicate f(R) gravity models with disappearing cosmological constant and observational constraints on the model parameters

We study the $f(R)$ theory of gravity using metric approach. In particular we investigate the recently proposed model by Hu-Sawicki, Appleby $-$ Battye and Starobinsky. In this model, the cosmological constant is zero in flat space time. The model passes both the Solar system and the laboratory tests. But the model parameters need to be fine tuned to avoid the finite time singularity recently pointed in the literature. We check the concordance of this model with the $H(z)$ and baryon acoustic oscillation data. We find that the model resembles the $\Lambda$CDM at high redshift. However, for some parameter values there are variations in the expansion history of the universe at low redshift.Comment: 16 pages and 9 figures, typos corrected, few references and minor clarifications added, revised version to appera in PR