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关键词： Electronic mail   Additives   Standards   Recurrent neural networks   Long short term memory   Computer science   Text categorization   Aggregation functions   Choquet integral   LSTM   recurrent neural networks (RNNs)   vector Choquet integral (VCI)  

摘要： Choquet integral is a widely used aggregation operator on 1-D and interval-valued information, since it is able to take into account the possible interaction among data. However, there are many cases where the information taken into account is vectorial, such as long short-term memories (LSTM). LSTM units are a kind of recurrent neural networks that have become one of the most powerful tools to deal with sequential information since they have the power of controlling the information flow. In this article, we first generalize the standard Choquet integral to admit an input composed by n-dimensional vectors, which produces an n-dimensional vector output. We study several properties and construction methods of vector Choquet integrals (VCIs). Then, we use this integral in the place of the summation operator, introducing in this way the new VCI-LSTM architecture. Finally, we use the proposed VCI-LSTM to deal with two problems: 1) sequential image classification;2) text classification.

摘要： The words "Programming is the second literacy" were coined more than 40 years ago [13], but never came to life. The paper develops and details that old slogan by proposing that the mainstream mathematics education in schools should merge with education in computer science/programming. Of course, this means a deep structural reform of school mathematics education. We are not talking about adapting the 20th century mathematics to the 21st century-as it outlined in [10, 19], we mean the 21st century mathematics education for the 21st century mathematics. To the best of our knowledge, this paper is perhaps the first known attempt to start a proper feasibility study for this reform. The scope of the paper does not allow us to touch the delicate socio-political (and financial) sides of the reform, we are looking only at general curricular and didactic aspects and possible directions of the reform. In particular, we indicate approaches to development of a Domain Specifiic Language (DSL) as a basis for all programming aspects of a new course.

关键词： Big Data   Data models   Unsolicited e-mail   Smoothing methods   Context modeling   Computer science   Computational modeling   Big data   e-commerce   review spammer detection   spam reviews  

摘要： The growing consumerism has led to the importance of online reviews on the Internet. Opinions voiced by these reviews are taken into consideration by many consumers for making financial decisions online. This has led to the development of opinion spamming for profitable motives or otherwise. This work has been done to tackle the challenge of identifying such spammers, but the scale of the real-world review systems demands this problem to be tackled as a big data challenge. So, an effort has been made to detect online review spammers using the principle of big data. In this article, a rating-based model has been studied under the light of large-scale datasets (more than 80 million reviews by 20 million reviewers) using the Hadoop and Spark frameworks. Scale effects have been identified and mitigated to provide better context to large review systems. An improved computational framework has been presented to compute the overall spamcity of reviewers using exponential smoothing. The value of the smoothing factor was set empirically. Finally, future directions have been discussed.

关键词： Special issues and sections   History   Europe   Surveys   Machine intelligence   Informatics   Artificial intelligence   special issues and sections   artificial intelligence   cybernetics   computer science   informatics   computer metaphor  

摘要： While artificial intelligence (AI) as a technology has been gaining widespread media and popular attention, its historical analysis is still in its infancy. As Jon Agar noted, "There is a surprising absence in the secondary literature of survey histories of artificial intelligence written by professional historians of science" [4, p. 291].1 When we began our own project on the history of AI in the Federal Republic of Germany,2 we found that we had to agree: Each project member-there are five of us (Florian Muller, Dinah Pfau, Helen Piel, Rudolf Seising, and Jakob Tschandl)-individually investigates one subject area of AI and has often found little historical work.3 What is more, the available histories, both monographs and articles, strongly focus on US developments (occasionally including British developments, Alan Turing, and Donald Michie) and are often written by practitioners and nonhistorians [12], [14], [16], [25], [34], [42], [63]. This prevalence of practitioner (as well as popular) accounts is being replicated outside the US too [9], [10], [11], [53]. While valuable as sources, these can only be a first step toward a thorough historical analysis of AI that extends beyond its US origins. This Special Issue therefore collects several histories of AI in Europe by historians and media theorists.

关键词： Costs   Quality of service   Bandwidth   Servers   Optimization   Computer science   Systematics   Cloud edge computing   content delivery   Index Terms   live streaming   resource scheduling   traffic engineering  

摘要： Even though conventional wisdom claims that in order to improve viewer engagement, the cloud-edge providers should serve the viewers with the nearest edge nodes, however, we show that doing this for crowdsourced live streaming (CLS) services can introduce significant costs inefficiency. In this paper, we first carry out large-scale measurement analysis by using the real-world service data from Huawei Cloud, a representative cloud-edge provider in China. We observe that the massive number of channels has proposed great burdens to the operating expenditure of the cloud-edge providers, and most importantly, unbalanced viewer distribution makes the edge nodes suffer significant costs inefficiency. To tackle the above concerns, we propose AggCast, a novel CLS scheduling framework to optimize the edge node utilization for the cloud-edge provider. The core idea of AggCast is to aggregate some viewers that are initially scattered on different regions, and assign them to fewer pre-selected nodes, thereby reducing bandwidth costs. In particular, by integrating the useful insights obtained from our large-scale measurement, AggCast can not only ensure that quality of experience (QoS) does not suffer degradation, but also satisfy the systematic requirements of CLS services. AggCast has been A/B tested and fully deployed. The online and trace-driven experiments show that, compared to the most prevalent method, AggCast saves over 16.3% back-to-source (BTS) bandwidth costs while significantly improving QoS (startup latency, stall frequency and stall time are reduced over 12.3%, 4.57% and 3.91%, respectively).

关键词： Costs   Software as a service   Quality of service   Web services   Predictive models   Task analysis   Computer science   Optimization   service composition   software adaptation   technical debt  

摘要： Given the changing workloads from the tenants, it is not uncommon for a service composition running in the multi-tenant SaaS cloud to encounter under-utilization and over-utilization on the component services. Both cases are undesirable and it is therefore nature to mitigate them by recomposing the services to a newly optimized composition plan once they have been detected. However, this ignores the fact that under-/over-utilization can be merely caused by temporary effects, and thus the advantages may be short-term, which hinders the long-term benefits that could have been created by the original composition plan, while generating unnecessary overhead and disturbance via recomposition. In this article, we propose DebtCom, a framework that determines whether to trigger recomposition based on the technical debt metaphor and time-series prediction of workload. In particular, we propose a service debt model, which has been explicitly designed for the context of service composition, to quantify the debt. Our core idea is that recomposition can be unnecessary if the under-/over-utilization only cause temporarily negative effects, and the current composition plan, although carries debt, can generate greater benefit in the long-term. We evaluate DebtCom on a large scale service system with up to 10 abstract services, each of which has 100 component services, under real-world dataset and workload traces. The results confirm that, in contrast to the state-of-the-art, DebtCom achieves better utility while having lower cost and number of recompositions, rendering each composition plan more sustainable.

关键词： Artificial intelligence   Cybernetics   History   Pragmatics   Europe   Economics   Social factors   Government  

摘要： AI research and development in the German Democratic Republic (GDR) can be seen as paradigmatic for the phase of late socialism. The imperatives of the socialist project and its economic ramifications in the endgame of the Cold War left a distinct imprint on AI. The GDR adopted a pragmatic approach to AI, which this article examines. It highlights the various strands and applications of late socialist AI research, encompassing both everyday applications and advanced scientific endeavors. Moving beyond the prevailing focus on U.S. research within the military-industrial complex, this article situates AI research within the broader history of the GDR, Central, and Eastern Europe. This study employs methods from science and technology studies to analyze AI objects, particularly chess computers, as indicators of the proliferation of AI within the everyday practices of the GDR. Through a thorough examination of a widely circulated computer magazine, this overview illustrates the diverse range of AI applications in the GDR, spanning areas such as planning, industrial management, state administration, science, public health, and pervasive surveillance. In this context, high-tech solutions were deployed alongside decaying industrial infrastructure, while utopian visions of intelligent machines intersected with ideological exhaustion, and health care applications were juxtaposed with fleeing doctors. These ambivalences reflect the complex state of the GDR in late socialism. Nevertheless, researchers and engineers worked on prototypes for image recognition, language processing, automatic reasoning and basic AI technologies, including programming languages and specialized hardware.

关键词： computational thinking   engineering   epistemic   science   science and engineering practices   verbal support  

摘要： Elementary teachers are tasked with the challenge of implementing Next Generation Science Standards-aligned projects that integrate science, technology, engineering, mathematics, and computer science (STEM + CS) in a variety of classroom contexts. This study investigates how teachers verbally support students in two classrooms, one general education class and one inclusive class with a larger proportion of students with individualized educational plans, to engage in a Next Generation Science Standards-aligned, STEM + CS unit. Teachers' verbal support for students to understand how (pragmatic) and when and why (epistemic) to use practices was examined during whole-class discussions for a 4-week unit in science, engineering, and computer science-focused lessons. Bi-weekly teacher surveys and weekly teacher interviews provided insight into the teachers' perceptions of students and project activities in each class section. Teachers reported instructional decisions to modify their enactment of the interdisciplinary curricular materials for the Inclusive Class and discussed their rationales for these modifications. Results suggest that instructional decisions that teachers made in how to verbally support students may depend upon their own knowledge of the different disciplines being integrated, their prior beliefs of students in different classroom contexts, and their in-the-moment perceptions of student needs. These factors may have led to different learning experiences for the students in each class section. Findings underscore the need for more research to better understand what kinds of support students and teachers need to be able to integrate engineering, science, and computer science content and practices within their elementary classrooms and provide equitable learning opportunities for all students.

关键词： Employment  

摘要： This article presents my observations on how computing and computing education have evolved throughout my professional career;it concludes with some guesses about changes that may come in the future.

关键词： High performance computing   Database systems   Information management   Translational research   Computer science  

摘要： High-performance computing (HPC) has become an indispensable tool for solving diverse problems in science and engineering. Harnessing the power of HPC is not just a matter of efficient computation, however;it also calls for the efficient management of vast quantities of scientific data. This presents daunting challenges: rapidly evolving storage technology has motivated a shift toward increasingly complex, heterogeneous storage architectures that are difficult to optimize, and scientific data management needs have become every bit as diverse as the application domains that drive them. There is a clear need for agile, adaptable storage solutions that can be customized for the task and platform at hand. This motivated the establishment of the Mochi composable data service project. The Mochi project provides a library of robust, reusable, modular, and connectable data management components and microservices along with a methodology for composing them into specialized distributed data services. Mochi enables rapid deployment of custom data services with a high degree of developer productivity while still effectively leveraging cutting-edge HPC hardware. This article explores how the principles of translational computer science have been applied in practice in Mochi to achieve these goals.