OpenCL Actors - Adding Data Parallelism to Actor-based Programming with CAF

The actor model of computation has been designed for a seamless support of concurrency and distribution. However, it remains unspecific about data parallel program flows, while available processing power of modern many core hardware such as graphics processing units (GPUs) or coprocessors increases the relevance of data parallelism for general-purpose computation. In this work, we introduce OpenCL-enabled actors to the C++ Actor Framework (CAF). This offers a high level interface for accessing any OpenCL device without leaving the actor paradigm. The new type of actor is integrated into the runtime environment of CAF and gives rise to transparent message passing in distributed systems on heterogeneous hardware. Following the actor logic in CAF, OpenCL kernels can be composed while encapsulated in C++ actors, hence operate in a multi-stage fashion on data resident at the GPU. Developers are thus enabled to build complex data parallel programs from primitives without leaving the actor paradigm, nor sacrificing performance. Our evaluations on commodity GPUs, an Nvidia TESLA, and an Intel PHI reveal the expected linear scaling behavior when offloading larger workloads. For sub-second duties, the efficiency of offloading was found to largely differ between devices. Moreover, our findings indicate a negligible overhead over programming with the native OpenCL API.Comment: 28 page

Near-field properties of plasmonic nanostructures with high aspect ratio

Using the Green's dyad technique based on cuboidal meshing, we compute the electromagnetic field scattered by metal nanorods with high aspect ratio. We investigate the effect of the meshing shape on the numerical simulations. We observe that discretizing the object with cells with aspect ratios similar to the object's aspect ratio improves the computations, without degrading the convergency. We also compare our numerical simulations to finite element method and discuss further possible improvements

Multi-criteria governmental crop planning problem based on an integrated AHP-PROMETHEE approach

The study uses analytic hierarchy process (AHP) and preference ranking organisation method for enrichment evaluations (PROMETHEE) to deal with the crop planning problem as a multi-criteria decision-making problem, for governmental lands in Gaza Strip under two conditions: the normal economy condition and the resistant economy condition. These two conditions are studied from the governmental point of view. The study goal is to rank crops according to some considered criteria. Crops are divided into eight types that include vegetables, fruits, citrus, olives, palms, export crops, field crops and medical and aromatic crops. The developed AHP and PROMETHEE compare crops with respect to seven main criteria, namely; economical, financial, marketing, environmental, technical, political and social criteria. AHP is used to obtain criteria weights to be used as input for PROMETHEE to outrank alternatives. The

Multi criteria governmental crop planning problem: an analytic hierarchy approach

The goal of this study is to rank crops to cultivate in the governmental agricultural lands in Gaza Strip using AHP methodology as a Multi Criteria Decision Making (MCDM) tool. This study is applied under the normal condition, from the governmental point of view. Seven main criteria were first identified consisting of economical, financial, marketing, environmental, technical, political, and social criteria, while thirty one sub-criteria were then identified. Crops were divided into eight types that include vegetables, fruits, citrus, olives, palms, export crops, field crops and medical and aromatic crops. The results indicate that the economic criteria are the most important criteria as they represent 0.33 of the total weight, while the technical criteria are the least important criteria as they represent 0.07 of the total weight. Sub-criteria weights indicate that the contribution to GDP sub-criterion is the most important one with respect to the goal as it has 0.103 of the total weight. Cropping pattern is skewed towards export crops, citrus and vegetables

Automatic Verification of Erlang-Style Concurrency

This paper presents an approach to verify safety properties of Erlang-style, higher-order concurrent programs automatically. Inspired by Core Erlang, we introduce Lambda-Actor, a prototypical functional language with pattern-matching algebraic data types, augmented with process creation and asynchronous message-passing primitives. We formalise an abstract model of Lambda-Actor programs called Actor Communicating System (ACS) which has a natural interpretation as a vector addition system, for which some verification problems are decidable. We give a parametric abstract interpretation framework for Lambda-Actor and use it to build a polytime computable, flow-based, abstract semantics of Lambda-Actor programs, which we then use to bootstrap the ACS construction, thus deriving a more accurate abstract model of the input program. We have constructed Soter, a tool implementation of the verification method, thereby obtaining the first fully-automatic, infinite-state model checker for a core fragment of Erlang. We find that in practice our abstraction technique is accurate enough to verify an interesting range of safety properties. Though the ACS coverability problem is Expspace-complete, Soter can analyse these verification problems surprisingly efficiently.Comment: 12 pages plus appendix, 4 figures, 1 table. The tool is available at http://mjolnir.cs.ox.ac.uk/soter

The SCARE 2020 Guideline: Updating Consensus Surgical CAse REport (SCARE) Guidelines

INTRODUCTION: The SCARE Guidelines were first published in 2016 and were last updated in 2018. They provide a structure for reporting surgical case reports and are used and endorsed by authors, journal editors and reviewers, in order to increase robustness and transparency in reporting surgical cases. They must be kept up to date in order to drive forwards reporting quality. As such, we have updated these guidelines via a DELPHI consensus exercise. METHODS: The updated guidelines were produced via a DELPHI consensus exercise. Members were invited from the previous DELPHI group, as well as editorial board members and peer reviewers of the International Journal of Surgery Case Reports. The expert group completed an online survey to indicate their agreement with proposed changes to the checklist items. RESULTS: A total of 54 surgical experts agreed to participate and 53 (98%) completed the survey. The responses and suggested modifications were incorporated into the new 2020 guideline. There was a high degree of agreement amongst the SCARE Group, with all modified SCARE items receiving over 70% scores 7-9. CONCLUSION: A DELPHI consensus exercise was completed and an updated and improved SCARE Checklist is now presented

RELEASE: A High-level Paradigm for Reliable Large-scale Server Software

Erlang is a functional language with a much-emulated model for building reliable distributed systems. This paper outlines the RELEASE project, and describes the progress in the first six months. The project aim is to scale the Erlang’s radical concurrency-oriented programming paradigm to build reliable general-purpose software, such as server-based systems, on massively parallel machines. Currently Erlang has inherently scalable computation and reliability models, but in practice scalability is constrained by aspects of the language and virtual machine. We are working at three levels to address these challenges: evolving the Erlang virtual machine so that it can work effectively on large scale multicore systems; evolving the language to Scalable Distributed (SD) Erlang; developing a scalable Erlang infrastructure to integrate multiple, heterogeneous clusters. We are also developing state of the art tools that allow programmers to understand the behaviour of massively parallel SD Erlang programs. We will demonstrate the effectiveness of the RELEASE approach using demonstrators and two large case studies on a Blue Gene

The importance of socio-economic context for social marketing models for improving reproductive health: Evidence from 555 years of program experience

BACKGROUND: Over the past two decades, social marketing programs have become an important element of the national family planning and HIV prevention strategy in several developing countries. As yet, there has not been any comprehensive empirical assessment to determine which of several social marketing models is most effective for a given socio-economic context. Such an assessment is urgently needed to inform the design of future social marketing programs, and to avoid that programs are designed using an ineffective model. METHODS: This study addresses this issue using a database of annual statistics about reproductive health oriented social marketing programs in over 70 countries. In total, the database covers 555 years of program experience with social marketing programs that distribute and promote the use of oral contraceptives and condoms. Specifically, our analysis assesses to what extent the model used by different reproductive health social marketing programs has varied across different socio-economic contexts. We then use random effects regression to test in which socio-economic context each of the models is most successful at increasing use of socially marketed oral contraceptives and condoms. RESULTS: The results show that there has been a tendency to design reproductive health social marketing program with a management structure that matches the local context. However, the evidence also shows that this has not always been the case. While socio-economic context clearly influences the effectiveness of some of the social marketing models, program maturity and the size of the target population appear equally important. CONCLUSIONS: To maximize the effectiveness of future social marketing programs, it is essential that more effort is devoted to ensuring that such programs are designed using the model or approach that is most suitable for the local context

Model Analisis Prediksi Kebangkrutan Bank Swasta Nasional Periode 2002-2006

There are two main objectives to be achieved by this study:to determine the accuracy level of prediction models of health national private banks using CAMEL ratios, and model the value of Z for the national private commercial banks by using multiple discriminant analysis (MDA) as well as Altman Z values on the model. Determination of the model using the Z value ratios banking health of Capital, Assets, Earnings and Liability (CAEL), then create a new Z value model specifically for national private commercial bank in Indonesia by using statistical analysis of MDA, with SPSS. The samples used were 30 banks, consisting of 19 survived banks in 2002 and 11 bankrupt banks in the same year. The results showed that the model value of Z in the year 2003-2006 cannot reach good accuracy when measured on a per year. Instead, the new Z value model generated by this study has better accuracy in predicting the rate of bankruptcy cases nationwide private commercial bank in Indonesia (86.7%) in 2002 and an average accuracy of 71.67% for the 4-year period of the review

Preferred reporting of case series in surgery (PROCESS) 2023 guidelines.

INTRODUCTION: The PROCESS guidelines were developed in 2016 in order to improve the reporting quality of surgical case series. Since its inception, it has been updated twice, in 2018 and 2020, and has been cited over 1000 times. PROCESS guidelines have enjoyed great acceptance within the surgical research community. Our aim is to update the PROCESS guidelines in order to maintain its applicability in the field of surgical research. METHODS: A PROCESS 2023 steering group was created. By working in collaboration, members of this group came up with proposals to update the PROCESS 2020 guidelines. These proposals were presented to an expert panel of researchers, who in turn scrutinised these proposals and decided whether they should become part of PROCESS 2023 guidelines or not, through a Delphi consensus exercise. RESULTS: A total of 38 people participated in the development of PROCESS 2023 guidelines. The majority of items received a score between 7 and 9 from >70% of the participants, indicating consensus with the proposed changes to those items. However, two items (3c and 6a) received a score between 7 and 9 from <70% of the participants, indicating a lack of consensus with the proposed changes to those items. Those items will remain unchanged. DISCUSSION: The updated PROCESS 2023 guidelines are presented with an aim to continue improving the reporting quality of case series in surgery