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关键词： Random variables   Information theory   Correlation   Couplings   Task analysis   Computer science   Protocols   Common randomness   secret key generation   channel simulation   correlation generation   interactive communication  

摘要： The task of manipulating correlated random variables in a distributed setting has received attention in the fields of both Information Theory and Computer Science. Often shared correlations can be converted, using a little amount of communication, into perfectly shared uniform random variables. Such perfect shared randomness, in turn, enables the solutions of many tasks. Even the reverse conversion of perfectly shared uniform randomness into variables with a desired form of correlation turns out to be insightful and technically useful. In this article, we describe progress-to-date on such problems and lay out pertinent measures, achievability results, limits of performance, and point to new directions.

关键词： Computer science   Mathematics and computing   Quantum physics  

摘要： If it holds up, it will solve in one fell swoop a number of related problems in pure mathematics, quantum mechanics and a branch of computer science known as complexity theory. According to work by physicist Boris Tsirelson5, who reformulated the problem, this also means that it is impossible to calculate the amount of correlation that two such systems can display across space when entangled. [...]it could be difficult to even conceive an experiment that could test quantum weirdness on an intrinsically infinite system, she says.

关键词： Smart grids   Wireless sensor networks   Wireless communication   Reliability   Time factors   Real-time systems   Computer science   Broadcast   communications   delay   neighborhood area network (NAN)   optimization  

摘要： Neighborhood area networks (NANs) are essential communication infrastructure in smart grid. They support communications for various applications including time-critical ones. A typical NAN communication scenario is to send commands from a control center simultaneously to a large number of nodes, demanding low-latency broadcast communications. This is challenging due to the limited bandwidth and large number of nodes in wireless NANs. While some broadcast schemes, e.g., opportunistic flooding, have been developed for general wireless sensor networks, they are not optimized for smart grid NANs with unique characteristics and low-latency requirements for time-critical applications. Therefore, a constrained broadcast scheme with minimized latency (CBS-ML) is presented in this paper for low-latency NAN communications. To avoid traffic congestion, it constrains the broadcast to a small number of core nodes. Theoretical developments are presented to show how to select core nodes based on network topology and link reliability. Simulations are conducted to demonstrate the proposed CBS-ML.

关键词： Conferences   IEEE Service awards   Internet of Things   Computer science   Cloud computing   Micromechanical devices  

摘要： The Technical Committee on the Internet of the IEEE Computer Society (IEEE-CS TCI, or TCI in short) is a forum that the Internet community can get together to work for furthering the advancement of the Internet, ranging from its underlying technologies to the applications it supports. TCI’s interests span many areas in computer science and engineering, and TCI activities aim to support its mission. An update of the recent TCI activities is presented.

关键词： NONFICTION   IRAN-Saudi Arabia relations  

关键词： Computer science   DNA   Next-generation sequencing  

摘要： Because of its longevity and enormous information density, DNA is considered a promising data storage medium. In this work, we provide instructions for archiving digital information in the form of DNA and for subsequently retrieving it from the DNA. In principle, information can be represented in DNA by simply mapping the digital information to DNA and synthesizing it. However, imperfections in synthesis, sequencing, storage and handling of the DNA induce errors within the molecules, making error-free information storage challenging. The procedure discussed here enables error-free storage by protecting the information using error-correcting codes. Specifically, in this protocol, we provide the technical details and precise instructions for translating digital information to DNA sequences, physically handling the biomolecules, storing them and subsequently re-obtaining the information by sequencing the DNA. Along with the protocol, we provide computer code that automatically encodes digital information to DNA sequences and decodes the information back from DNA to a digital file. The required software is provided on a Github repository. The protocol relies on commercial DNA synthesis and DNA sequencing via Illumina dye sequencing, and requires 1-2 h of preparation time, 1/2 d for sequencing preparation and 2-4 h for data analysis. This protocol focuses on storage scales of similar to 100 kB to 15 MB, offering an ideal starting point for small experiments. It can be augmented to enable higher data volumes and random access to the data and also allows for future sequencing and synthesis technologies, by changing the parameters of the encoder/decoder to account for the corresponding error rates.

关键词： Software   Computer science   Guidelines   Industries   Software architecture   Cognition   Controlled experiment   understandability   temporal property   linear temporal logic   property specification patterns   complex event processing   event processing language  

摘要： Temporal properties are important in a wide variety of domains for different purposes. For example, they can be used to avoid architectural drift in software engineering or to support the regulatory compliance of business processes. In this work, we study the understandability of three major temporal property representations: (1) Linear Temporal Logic (LTL) is a formal and well-established logic that offers temporal operators to describe temporal properties;(2) Property Specification Patterns (PSP) are a collection of recurring temporal properties that abstract underlying formal and technical representations;(3) Event Processing Language (EPL) can be used for runtime monitoring of event streams using Complex Event Processing. We conducted two controlled experiments with 216 participants in total to study the understandability of those approaches using a completely randomized design with one alternative per experimental unit. We hypothesized that PSP, as a highly abstracting pattern language, is easier to understand than LTL and EPL, and that EPL, due to separation of concerns (as one or more queries can be used to explicitly define the truth value change that an observed event pattern causes), is easier to understand than LTL. We found evidence supporting our hypotheses which was statistically significant and reproducible.

关键词： Education computing  

摘要： Although it has never been rigorously demonstrated, there is a common belief that grades in computer science courses are bimodal. We statistically analyzed 778 distributions of final course grades from a large research university and found that only 5.8% of the distributions passed tests of multimodality. We then devised a psychology experiment to understand why CS educators believe their grades to be bimodal. We showed 53 CS professors a series of histograms displaying ambiguous distributions that we asked them to categorize. A random half of participants were primed to think about the fact that CS grades are commonly thought to be bimodal;these participants were more likely to label ambiguous distributions as "bimodal." Participants were also more likely to label distributions as bimodal if they believed that some students are innately predisposed to do better at CS. These results suggest that bimodal grades are instructional folklore in CS, caused by confirmation bias and instructor beliefs about their students.

关键词： Information science   Computer science   Vertical fragmentation   Clustering   Data allocation   Data replication   DDBS   Greedy algorithms   ASGOP  

摘要： In the literature of distributed database system (DDBS), several methods sought to meet the satisfactory reduction on transmission cost (TC) and were seen substantially effective. Data Fragmentation, site clustering, and data distribution have been considered the major leading TC-mitigating influencers. Sites clustering, on one hand, aims at grouping sites appropriately according to certain similarity metrics. On the other hand, data distribution seeks to allocate the fragmented data into clusters/sites properly. The combination of these methods, however, has been shown fruitful concerning TC reduction along with network overheads. In this work, hence, a heuristic clustering-based approach for vertical fragmentation and data allocation is meticulously designed. The focus is directed on proposing an influential solution for improving relational DDBS throughputs across an aggregated similarity-based fragmentation procedure, an effective site clustering and a greedy algorithm-driven data allocation model. Moreover, the data replication is also considered so TC is further minimized. Through the delineated-below evaluation, the findings of experimental implementation have been observed to be promising.