Complete Program Synthesis for Linear Arithmetic

Synthesis of programs or their fragments is a way to write programs by providing only their meaning without worrying about the implementation details. It avoids the drawback of writing sequential code, which might be difficult to check, error-prone or tedious. Our contribution is to provide complete program synthesis algorithms with unbounded data types in decidable theories. We present synthesis algorithms for Linear Rational Arithmetic, Linear Integer Arithmetic and Parametrized Linear Integer Arithmetic. Our implementation and the associated Scala compiler plug-in have been used to implement Boolean Algebra for Presburger Arithmetic synthesis

Game Programming by Demonstration

The increasing adoption of smartphones and tablets has provided tens of millions of users with substantial resources for computation, communication and sensing. The availability of these resources has a huge potential to positively transform our society and empower individuals. Unfortunately, although the number of users has increased dramatically, the number of developers is still limited by the high barrier that existing programming environments impose. To understand possible directions for helping end users to program, we present Pong Designer, an environment for developing 2D physics games through direct manipulation of object behaviors. Pong Designer is built using Scala and runs on Android tablets with the multi-touch screen as the main input. We show that Pong Designer can create simple games in a few steps. This includes (multi-player and multi-screen) Pong, Brick Breaker, Pacman, Tilting maze. We make available Pong Designer as well as several editable games that we created using it. This paper describes the main principles behind Pong Designer, and illustrates the process of developing and customizing behavior in this approach

Towards Automating Grammar Equivalence Checking

We consider from practical perspective the (generally undecidable) problem of checking equivalence of context-free grammars. We present both techniques for proving equivalence, as well as techniques for finding counter-examples that establish non-equivalence. Among the key building blocks of our approach is a novel algorithm for efficiently enumerating and sampling words and parse trees from arbitrary context-free grammars; the algorithm supports polynomial time random access to words belonging to the grammar. Furthermore, we propose an algorithm for proving equivalence of context-free grammars that is complete for LL grammars, yet can be invoked on any context-free grammar, including ambiguous grammars. Our techniques successfully find discrepancies between different syntax specifications of several real-world languages, and is capable of detecting fine-grained incremental modifications performed on grammars. Our evaluation shows that our tool improves significantly on the existing available state of the art tools. In addition, we used these algorithms to develop an online tutoring system for grammars that we then used in an undergraduate course on computer language processing. On questions involving grammar constructions, our system was able to automatically evaluate the correctness of 95% equivalence questions: it disproved 74% of cases and proved 21% of them. This opens up the possibility of using our tool in massive open online courses to introduce grammars to large populations of students

Roombots-Towards Decentralized Reconfiguration with Self-Reconfiguring Modular Robotic Metamodules

This paper presents our work towards a decentralized reconfiguration strategy for self-reconfiguring modular robots, assembling furniture-like structures from Roombots metamodules. We explore how reconfiguration by locomotion from a configuration A to a configuration B can be controlled in a distributed fashion. This is done using Roombots metamodules—two Roombots modules connected serially—that use broadcast signals, lookup tables of their movement space, assumptions about their neighborhood, and connections to a structured surface to collectively build desired structures without the need of a centralized planne

Технологические решения для строительства разведочной вертикальной скважины глубиной 1710 метров на нефтяном месторождении (Томская область)

Цель работы – проектирование вертикальной разведочной скважины глубиной 1710 метров. В процессе работы был составлен проект на строительство вертикаль-ной разведочной скважины на нефть глубиной 1710 м (по вертикали). Разработаны мероприятия по организации строительству, охране труда и окружающей среды. В работе рассмотрен вопрос о возможности применения бурового яса, рассмотрены варианты компоновок низа бурильной колонны с их применением.The purpose of the work is to design a vertical exploration well with a depth of 1710 meters. In the course of work, a project was drawn up for the construction of a vertical exploration well for oil with a depth of 1710 m (vertical). Developed measures for the organization of construction, labor and environmental protection. The paper discusses the possibility of using a drilling jar and bottomhole assembly with drilling jar

Reply to: New Meta- and Mega-analyses of Magnetic Resonance Imaging Findings in Schizophrenia: Do They Really Increase Our Knowledge About the Nature of the Disease Process?

This work was supported by National Institute of Biomedical Imaging and Bioengineering Grant No. U54EB020403 (to the ENIGMA consortium)

Performance of ALICE AD modules in the CERN PS test beam

Two modules of the AD detector have been studied with the test beam at the T10 facility at CERN. The AD detector is made of scintillator pads read out by wave-length shifters (WLS) coupled to clean fibres that carry the produced light to photo-multiplier tubes (PMTs). In ALICE the AD is used to trigger and study the physics of diffractive and ultra-peripheral collisions as well as for a variety of technical tasks like beam-gas background monitoring or as a luminometer. The position dependence of the modules' efficiency has been measured and the effect of hits on the WLS or PMTs has been evaluated. The charge deposited by pions and protons has been measured at different momenta of the test beam. The time resolution is determined as a function of the deposited charge. These results are important ingredients to better understand the AD detector, to benchmark the corresponding simulations, and very importantly they served as a baseline for a similar device, the Forward Diffractive Detector (FDD), being currently built and that will be in operation in ALICE during the LHC Runs 3 and 4.Peer reviewe

Periodontal status of rheumatoid arthritis patients in khartoum state

<p>Abstract</p> <p>Background</p> <p>Few studies have investigated the periodontal condition among Rheumatoid arthritis in Sudan. The present study described the periodontal condition among Sudanese patients suffering from rheumatoid arthritis and to compare them with those of non-rheumatic subjects.</p> <p>Methods</p> <p>A group of eighty rheumatoid arthritis patients was selected from Patient's Rheumatoid Clinics in Khartoum State during the period of January to May 2010. A control group of eighty patients with the same age and gender was selected for the study. Both Rheumatoid arthritis patients and the control group were examined for their plaque index, gingival index, and clinical attachment loss.</p> <p>Results</p> <p>The results revealed that there were no significant differences in plaque and gingival index among study and control groups, with mean plaque index of (1.25 ± 0.4) for patients and (1.17 ± 0.28) for the control group (p-value is 0.3597). The mean gingival index was (1.2 ± 0.24) for the patients and (1.2 ± 0.33) for the control (p = is 0.3049). The results showed statistically significant differences in clinical attachment loss between study and control groups, with mean clinical attachment loss of (1.03 ± 0.95) for the study group and (0.56 ± 0.63) for the control group (p = 0.0002). The study revealed that no association exists between the type of drug used to treat rheumatoid arthritis (NSAIDs & DMARDs) and the periodontal parameters (plaque index, gingival index, and clinical attachment loss).</p> <p>Conclusion</p> <p>A significant relationship between periodontal disease and Rheumatoid Arthritis does exist, but no difference between plaque and gingival index has been detected among study and control groups.</p