Sharif Digital Repository

Much attention has been directed to different aspects of the design of pipelines. Design of the control logic of non-linear pipelines has however, been considered as a subsidiary issue in that an RTL description for such logic can easily be obtained from a behavioral description, with the use of widely available synthesis tools. But, as the complexity of a non-linear pipeline increases, so does the complexity of the control logic. The complexity may be to an extent that obtaining even a behavioral description for the control logic is rendered difficult. This paper focuses on further automating the development of systems consisting of non-linear or multi-function pipelines by proposing an... 

In this study, the performance of virtual cut-through switching in the cube-based OTIS architecture, an optoelectronic interconnection architecture for multicomputer systems, is empirically analyzed. Deadlock-free deterministic and adaptive minimal path routing algorithms for this architecture are introduced, and the effects of different network and traffic parameters on average message latency are investigated. This analysis presents a relatively more realistic view of the OTIS architecture than that presented in previous work by considering issues related to a lower level of abstraction (the routing and switching of messages). Among other results, the analysis indicates that depending on... 

In this paper, routing properties of cube-based optoelectronic OTIS networks are explored. We show emulations of various cubical network topologies on their OTIS augmented variants, including the nD grid networks, shuffle-exchange, and de Brujin networks. An analytical performance model for OTIS-cube networks is proposed. The model is validated by means of comparison with rigorously obtained simulation results. Using this model, the performance characteristics of the OTIS-hypercube network are evaluated in view of a number of different constraints. Moreover, we compare the performance characteristics of the OTIS-hypercube with that of equivalent fully-electronic networks under various... 

The ability to perform multicast communication efficiently in parallel computing systems is increasingly becoming an essential feature of these systems. Therefore, any emerging parallel architecture must be able to provide effective multicasting performance. OTIS-based multi-computer systems are parallel systems that efficiently exploit optical connections between distant nodes, while using electronic connections for physically close processors. No previous work has attempted to determine an optimal multicast communication scheme for OTIS networks. This paper presents two approaches to implement efficient multicast communication in wormhole-routed OTIS networks, for the two different... 

In optoelectronic OTIS architectures, electrical and optical interconnects are used for local and global communication, respectively. Interesting instances of the OTIS architecture are the OTIS-hypercube and OTIS-mesh. This paper conducts a performance evaluation and comparison of these networks under different structural conditions and traffic loads. All judgments made, are based on observations from extensive simulation results of the interconnection networks. We conclude that, when the OTIS-hypercube and equivalent 2-D OTIS-mesh are compared under the constraint of equal bisection bandwidth, the performance of the OTIS-hypercube is of superior performance. We however show that the... 

This study provides a stochastic dynamic programming model with a Markov chain that explicitly focuses on the customer as well as a new model for valuing the customers in the banking industry. The proposed framework calculates individual customer’s lifetime value dynamically. The study follows a stochastic dynamic programming model that is based on the Markov chain. The deduced findings are illustrated with supplementary context from an outstanding case study. The findings underline the importance of the stochastic model for calculating customer lifetime value based on customer behavior. The presented framework provides a beneficial way for future research and valuable insight for allocating... 

Twitter as one of the most important microblogging online social networks has attracted more than 200 million users in recent years. Although there have been several attempts on characterizing the Twitter by using incomplete sampled data, they have not been very successful to estimate the characteristics of the whole network. In this paper, we characterize Twitter by sampling from its social graph and user behaviors through a random walk based sampling technique called Respondent-Driven Sampling (RDS). To the best of our knowledge, for the first time RDS method and its estimator are used in order to obtain uniform unbiased estimation of several key structural and behavioral properties of... 

Traffic safety policies are still conventionally ranked on financial and environmental criteria in developing countries, yet the equity concept can be advantageously used as an integral part of the process of traffic safety policy making. Equity in transportation is defined as how appropriately and equally the impacts of transportation are distributed among different types of users. The main contribution of this research is to introduce traffic safety equity in transportation policy making. The authors advocate for a modeling framework that considers traffic safety equity as a focal point. The analytical network process overcomes the drawbacks of data intensive models that are so difficult... 

A double burden of malnutrition occurs when individuals, household members or communities experience both undernutrition and overweight. Here, we show geospatial estimates of overweight and wasting prevalence among children under 5 years of age in 105 low- and middle-income countries (LMICs) from 2000 to 2017 and aggregate these to policy-relevant administrative units. Wasting decreased overall across LMICs between 2000 and 2017, from 8.4% (62.3 (55.1–70.8) million) to 6.4% (58.3 (47.6–70.7) million), but is predicted to remain above the World Health Organization’s Global Nutrition Target of <5% in over half of LMICs by 2025. Prevalence of overweight increased from 5.2% (30 (22.8–38.5)... 

An amendment to this paper has been published and can be accessed via a link at the top of the paper. © 2020, The Author(s)  

Anemia is a globally widespread condition in women and is associated with reduced economic productivity and increased mortality worldwide. Here we map annual 2000–2018 geospatial estimates of anemia prevalence in women of reproductive age (15–49 years) across 82 low- and middle-income countries (LMICs), stratify anemia by severity and aggregate results to policy-relevant administrative and national levels. Additionally, we provide subnational disparity analyses to provide a comprehensive overview of anemia prevalence inequalities within these countries and predict progress toward the World Health Organization’s Global Nutrition Target (WHO GNT) to reduce anemia by half by 2030. Our results... 

Background: While there is a long history of measuring death and disability from injuries, modern research methods must account for the wide spectrum of disability that can occur in an injury, and must provide estimates with sufficient demographic, geographical and temporal detail to be useful for policy makers. The Global Burden of Disease (GBD) 2017 study used methods to provide highly detailed estimates of global injury burden that meet these criteria. Methods: In this study, we report and discuss the methods used in GBD 2017 for injury morbidity and mortality burden estimation. In summary, these methods included estimating cause-specific mortality for every cause of injury, and then...