4,750 research outputs found

    Skew Schur Function Representation of Directed Paths in a Slit

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    19 pages, 5 figures, accepted version (Journal of Combinatorics)19 pages, 5 figures, accepted version (Journal of Combinatorics)In this work, we establish a general relationship between the enumeration of weighted directed paths and skew Schur functions, extending work by Bousquet-M\'elou, who expressed generating functions of discrete excursions in terms of rectangular Schur functions

    Coral reef and associated habitat mapping using ALOS satellite imagery

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    Coral reefs are rich in biodiversity and ecosystem services. However increase in degradation are still occurring at an alarming rate. In management of this ecosystem, determination of its spatial distribution is of importance. Satellite imageries can be used to map distribution extent using spectral characteristics which is a fundamental parameter in mapping. The aims of this study were to determine the spectral characteristics of corals and associated habitats and to map its spatial distribution using 2009 ALOS advanced visible and near infrared radiometer type 2 (AVNIR-2) satellite imagery. Results indicated that coral and habitats surrounding the area display variation in the spectral characteristics magnitude but displays similar spectral curve. Spectral characteristics from the corals and surrounding habitats were determined by presence of benthic microalgae and calcium carbonate. Maximum likelihood classification on the image produced five main classes. Spatial distribution of coral and associated habitats indicated five main zones which are sandy shore zone, sandy intertidal zone, seagrass zone, coral/submerged sandy zone and rocky zone. Distribution of live corals indicated coverage of 0.54 km2, sea grass (0.94 km2), sandy bottom (1.31 km2) and rocky shores (0.19 km2). The results of this study indicated that ALOS satellite data was able to determine variation in spectral characteristics of coral reefs and other habitats thus is capable of mapping the ecosystems spatial distribution

    The Influence of the Upper Extremities Movement on Take-off in Vertical Jump

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    The positive influence of the upper extremities swing on the effect of take-off in jumping is well known. Such movement is used in vertical jump, long jump, high jump and others. This effect causes increase of the ground reaction force produced by each segment (Luhtanen and Komi, 1978) and in addition the upper extremities swing has also a coordinative meaning, for example while double overarm movement at running is to be change into parallel movement at take off (high jump), There are also such situations like in basketball and volleyball (Wielki and Dangre, 1983; Wilkerson, 1983) in which the desired arms swing is limited by the other task which has to be performed like blocking or passing the ball. Loss in the height of the vertical jump -while the arms swing is not executed -and diminishing ground reaction force at take-off and the possible changes in biomechanical variables during take-off, are the object of this experiment

    Acute-on-chronic Liver Failure: MELD Score 30-day Mortality Predictability and Etiology in a Pakistani Population

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    Background: Cirrhosis is a pathological condition that ultimately leads to liver failure. Acute on chronic liver failure (ACLF) has a high short term mortality rate. Viral hepatitis is the most common cause of liver failure in our local population. We carried out this study to identity the 30-day mortality and etiology of patients presenting with ACLF using Model for End-Stage Liver Disease (MELD) score predictability. Methodology: This was a descriptive case series, conducted at Sheikh Zayed Hospital, Lahore, Pakistan from January 31, 2018 to July 30, 2018. One hundred and eighty five patients who met the inclusion criteria were enrolled using 95% confidence level and 4% margin of error. Data was entered and analyzed with SPSS version 23.0. Numerical variables including age was presented by Mean ± S.D. Categorical variables i.e. gender, etiology of acute-on-chronic liver failure and 30-day mortality were presented by frequency and percentage. Data was stratified for age, gender, duration of chronic liver disease and MELD grade to address the effect modifiers. Post-stratification chi-square test was calculated using 95% significance (p≤0.05). Results: Majority of the enrolled patients were male (74.6%) while only 25.4% of the patients were female. One hundred and thirty patients (70.3%) had underlying viral hepatitis while twelve patients (6.5%) and forty three patients (23.2%) presented with alcoholic liver disease and drug-induced ACLF, respectively. Eighty patients (43.2%) died within 30 days of admission.The 30-day mortality with respect to MELD grade was statistically significant (p<0.001) with the highest mortality noted in grade-IV and thirty five patients (43.8%) dying within 30 days of admission (p<0.001). Grade-II and III MELD scores also contributed to the 30-day mortality with twenty three patients (28.8%) and nineteen patients (23.8%) dying within 30 days of admission (p<0.001). Conclusion: MELD scores are able to accurately predict the short-term mortality in patients with ACLF and viral hepatitis was the most common etiology in our population. Early detection and use of appropriate prognostic models may alleviate mortality and morbidity in paitents with ACLF

    A Framework for Protecting Cloud Users from Third Party Auditors

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    Cloud computing has merged to be a now computing paradigm that lets public to access shared pool of resources without capital investment. The users of cloud need to access resources through Internet in pay per use fashion. Thus there is increased use of storage services of cloud in the real world. This service is known as Infrastructure as a Service (IaaS). However, there are security concerns as this service runs in entrusted environment. To ensure data integrity many public verification or auditing schemes came into existence. Nevertheless, there is a concern when the so called Third Party Auditor (TPA) has malicious intentions. In such cases, protection is required against malicious TPAs. Towards this end, recently, Huang et al. proposed a scheme in which users can directly check the integrity of stored data using a feedback based audit scheme. TPA takes process proof from cloud server and gives feedback to cloud user. The feedback is unforgivable and the TPA cannot make any malicious attacks. Based on this scheme, in this paper, we implemented a prototype application that demonstrates the proof of concept. The empirical results are encouraging. DOI: 10.17762/ijritcc2321-8169.15065

    Lightweight Strategy for XOR PUFs as Security Primitives for Resource-constrained IoT device

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    Physical Unclonable Functions (PUFs) are promising security primitives for resource-constrained IoT devices. And the XOR Arbiter PUF (XOR-PUF) is one of the most studied PUFs, out of an effort to improve the resistance against machine learning attacks of probably the most lightweight delay-based PUFs - the Arbiter PUFs. However, recent attack studies reveal that even XOR-PUFs with large XOR sizes are still not safe against machine learning attacks. Increasing PUF stages or components and using different challenges for different components are two ways to improve the security of APUF-based PUFs, but more stages or components lead to more hardware cost and higher operation power, and different challenges for different components require the transmission of more bits during operations, which also leads to higher power consumption. In this paper, we present a strategy that combines the choice of XOR Arbiter PUF (XOR-PUF) architecture parameters with the way XOR-PUFs are used to achieve lightweights in hardware cost and energy consumption as well as security against machine learning attacks. Experimental evaluations show that with the proposed strategy, highly lightweight component-differentially challenged XOR-PUFs can withstand the most powerful machine learning attacks developed so far and maintain excellent intra-device and inter-device performance, rendering this strategy a potential blueprint for the fabrication and use of XOR-PUFs for resource-constrained IoT applications.Comment: arXiv admin note: text overlap with arXiv:2206.0131

    Modification of Levenberg-Marquardt Algorithm for Solve Two Dimension Partial Differential Equation

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    في هذه الدراسة تم تطوير طريقة جديدة تقوم على الشبكة العصبية من أجل حل المعادلات التفاضلية الجزئية البعدين. استخدام الشبكة العصبية المعدلة لتجنب عيوب خوارزمية التدريب لﭭنبرك – ماركوادت. أولا نقترح SVD تحليل القيمة المنفردة إلى J  و J-1  إذا كانت المصفوفة J(w) مستطيلة او منفردة . ثانيا نقترح حساب جديد إلى   μ بحيث ان  . نعتبر ان دالة الهدف الغير خطية  E(w) تملك مجموعة غير خالية من الحلول  W*  ونشير أن ‖ ‖ هو من المعيار 2  و E(w):  هي مستمرة وقابلة للاشتقاق وتحقق شرط  حيث ان L   هو ثابت ليبشيتز.In this paper we presented a new way based on neural network has been developed for solutione of two dimension  partial differential equations . A modified neural network use to over passing the Disadvantages of LM algorithm, in the beginning we suggest signaler value decompositions of Jacobin matrix (J) and inverse of Jacobin matrix( J-1), if a matrix rectangular or singular  Secondly, we suggest new calculation of μk , that ismk=|| E (w)||2    look the nonlinear execution equations E(w) = 0 has not empty solution W* and we refer   to the second norm in all cases ,whereE(w):  is continuously differentiable and E(x) is Lipeschitz  continuous, that is=|| E(w 2)- E(w 1)||£ L|| w  2- w  1|| ,where L  is Lipeschitz  constant

    Preparation, Characterization and Spectroscopic Study of New Tridentate Schiff Base and its Cu(II), Ni(II) and Zn(II) Metal Complexes

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    A new tridentate ligand has been synthesized derived from phenyl(pyridin-3-yl)methanone. Three coordinated metal complexes were prepared by complexation of the new ligand with Cu(II), Ni(II) and Zn(II) metal salts. The new Schiff base “benzyl -2-[phenyl(pyridin-3-yl)methylidene]hydrazinecarbodithioate” and the new metal complexes were characterized using various physico-chemical and spectroscopic techniques. From the analysis results, the expected structure to the metal complexes are octahedral in geometry for Cu(II) complex, square planner for Ni(II) and tetrahedral for Zn(II) complex. The new compounds are expected to show strong bioactivity against bacteria and cancer cells
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