Correctness Of Programs Research Articles

Designing a Risk Management Model for Continuously Reinforced Concrete Pavement (CRCP) Using Network Analysis

Project managers, using the correct economic program and tools for controlling threats and taking opportunities, can reach the goal. Purpose of managers in terms of cost, time, quality and safety depends on certain and uncertain factors. Uncertainties in estimation and feasibility studies are not measurable or are hidden from experts. Hence, having a comprehensive and complete plan that identifies, analyses, studies, evaluates and examines unforeseen incidents, technical mistakes which are not considered, and or hidden costs that are imposed at the time of execution of the project which had been no plans for them before, can minimize the project risk. In our country, using and benefiting from continuously reinforced concrete pavements (CRCP) in recent years has been increasing. Therefore, continuously reinforced concrete pavement application creates problems for managers during implementation in our country, due to being new. In this research, we have tried to use the Dematel method and network analysis to provide a model for review, identification, and rating, considering the most important risks of the armed concrete pavement, the ongoing construction of the honorary street, Eftekhari.

Complex Program Induction for Querying Knowledge Bases in the Absence of Gold Programs

Recent years have seen increasingly complex question-answering on knowledge bases (KBQA) involving logical, quantitative, and comparative reasoning over KB subgraphs. Neural Program Induction (NPI) is a pragmatic approach toward modularizing the reasoning process by translating a complex natural language query into a multi-step executable program. While NPI has been commonly trained with the ‘‘gold’’ program or its sketch, for realistic KBQA applications such gold programs are expensive to obtain. There, practically only natural language queries and the corresponding answers can be provided for training. The resulting combinatorial explosion in program space, along with extremely sparse rewards, makes NPI for KBQA ambitious and challenging. We present Complex Imperative Program Induction from Terminal Rewards (CIPITR), an advanced neural programmer that mitigates reward sparsity with auxiliary rewards, and restricts the program space to semantically correct programs using high-level constraints, KB schema, and inferred answer type. CIPITR solves complex KBQA considerably more accurately than key-value memory networks and neural symbolic machines (NSM). For moderately complex queries requiring 2- to 5-step programs, CIPITR scores at least 3× higher F1 than the competing systems. On one of the hardest class of programs (comparative reasoning) with 5–10 steps, CIPITR outperforms NSM by a factor of 89 and memory networks by 9 times. 1

A survey on the use of access permission-based specifications for program verification

Verifying the correctness and reliability of imperative and object-oriented programs is one of the grand challenges in computer science. In imperative programming models, programmers introduce concurrency manually by using explicit concurrency constructs such as multi-threading. Multi-threaded programs are prone to synchronization problems such as data races and dead-locks, and verifying API protocols in object-oriented programs is a non-trivial task due to improper and unexpected state transition at run time. This is in part due to the unexpected sharing of program states in such programs. With these considerations in mind, access permissions have been investigated as a means to reasoning about the correctness of such programs. Access permissions are abstract capabilities that characterize the way a shared resource can be accessed by multiple references.This paper provides a comprehensive survey of existing access permission-based verification approaches. We describe different categories of permissions and permission-based contracts. We elaborate how permission-based specifications have been used to ensure compliance of API protocols and to avoid synchronization problems in concurrent programs. We compare existing approaches based on permission usage, analysis performed, language and/or tool supported, and properties being verified. Finally, we provide insight into the research challenges posed by existing approaches and suggest future directions.

Weak persistency semantics from the ground up: formalising the persistency semantics of ARMv8 and transactional models

Emerging non-volatile memory (NVM) technologies promise the durability of disks with the performance of volatile memory (RAM). To describe the persistency guarantees of NVM, several memory persistency models have been proposed in the literature. However, the formal persistency semantics of mainstream hardware is unexplored to date. To close this gap, we present a formal declarative framework for describing concurrency models in the NVM context, and then develop the PARMv8 persistency model as an instance of our framework, formalising the persistency semantics of the ARMv8 architecture for the first time. To facilitate correct persistent programming, we study transactions as a simple abstraction for concurrency and persistency control. We thus develop the PSER (persistent serialisability) persistency model, formalising transactional semantics in the NVM context for the first time, and demonstrate that PSER correctly compiles to PARMv8. This then enables programmers to write correct, concurrent and persistent programs, without having to understand the low-level architecture-specific persistency semantics of the underlying hardware.

Automatic force plate contact detection protocol for computerized gait analysis

BackgroundThe usability and evaluability of a computerized gait analysis requires correct force plate foot contact, with the force measuring plates embedded in the ground, in order to obtain kinetic data. Research questionThis article describes a technical development that facilitates the process flow of computerized gait analysis. Software has been developed that automatically recognizes, counts and documents the correct force plate foot contacts MethodsA software program has been developed. Programming was done in Microsoft® C# using the ViconDatastreemSDK.dotNet® Dynamic Link Library (DLL) developed by Vicon®. The program queries the positions of the foot markers and the electrical signals of the force plates. Results and significanceThe program, which runs parallel to the Vicon® data acquisition software, simultaneously displays the information about the correct force plate foot contacts in a graphical user interface (GUI). After the measurement, an automatically generated protocol of the evaluable walks is available in tabular form

SPORT ACCOMPANIMENT OF SELF DEFENSE PENCAK SILAT BANJAR RAGA INSANI CLUB AT ARA PAYUNG VILLAGE

This community service activity is one form of the implementation of the Tri Dharma of Higher Education. This activity was carried out in order to help preserve the pencak silat banjar culture which is in the Village of Ara Payung. The main problem faced by partners is that in carrying out the training of pencak silat trainers, they do not yet have the ability to prepare training programs, variations in the practice of pencak silat in the art of motion are not many. And the lack of training facilities that exist in supporting a good training process, and supporting facilities. The output targets in this activity are: Trainers are able to make a good and correct training program in accordance with the rules of coaching. Availability of standard martial arts training facilities in accordance with the provisions. The method used to achieve the objectives of this activity is. Coaching clinic for the preparation of training programs for pencak silat coach, and mentoring for banjar pencak silat training. This service activity has resulted in an exercise program that is used in training at tha club, the trainer is able to arrange an exercise program that can be applied in training, increasing the variety of training in the Pencak Silat Raga Insani club. With the training and mentoring activities, the enthusiasm of the teenagers in the village of Ara Payung was higher in participating in the martial arts training in his village.Keywords: Instrument, Talent, Karate.

Regression verification for automated evaluation of students programs

Regression verification is a form of software verification based on formal static analysis of code, which is used, since recently, in several domains. In this paper we examine potentials of using it in one novel domain ? in automated evaluation of students programs. We propose an approach that provides precise assessment of functional correctness of student programs (while it does not address nor affect the teaching methodology). We describe our open-source, publicly available implementation of the approach, which is built on top of the compiler infrastructure LLVM and the software verification tool LAV. The results of evaluating the proposed approach on two real-world corpora of student programs and on a number of classic algorithms show that the proposed approach can be used as a precise and reliable supplementary technique in grading of student programs at introductory programming courses, algorithms courses and programming competitions.

Optimization of Numerical Control Program and Machining Simulation Based on VERICUT

In the machining process of large-scale complex curved surface, workers will encounter problems such as empty stroke of tool, collision interference, and overcut or undercut of the workpieces. This paper presents a method for generating the optimized tool path, compiling and checking the numerical control (NC) program. Taking the bogie frame as an example, the tool paths of all machining surface are optimized by the dynamic programming algorithm, Creo software is utilized to compile the optimized computerized numerical control (CNC) machining program, and VERICUT software is employed to simulate the machining process, optimize the amount of cutting and inspect the machining quality. The method saves the machining time, guarantees the correctness of NC program, and the overall machining efficiency is improved. The method lays a good theoretical and practical foundation for integration of the similar platform.

Nutrition, Physical Activity, and Prescription of Supplements in Pre- and Post-bariatric Surgery Patients: a Practical Guideline.

According to ASMBS, the rate of bariatric surgery increased from 158,000 in 2011 to 196,000 in 2015. Nevertheless, this growth in invasive techniques does not eliminate unhealthy habits, so lifestyle modification such as healthy nutrition and correct physical activity programs may improve surgical results. The objective of the present narrative review was to categorize the guidelines related to nutrition, physical activity, and supplement prescription before and after bariatric surgery. The main key words including nutrition, diet, physical activity, exercise, supplements, macronutrients, micronutrients, weight reduction, bariatric surgery, Roux-en-Y gastric bypass, sleeve gastrostomy, laparoscopic adjustable gastric banding, and biliopancreatic diversion with duodenal switch were searched in databases including PubMed/Medline, Cochrane, and some other sources such as Google scholar. The recommendations are classified based on the type of surgery. The indications for surgery and the type of bariatric surgery are not included in this review. This review helps medical teams, including bariatric surgeons, nutritionists, and sports medicine specialists, with proper management before and after bariatric surgery.

Stepping Stones to Inductive Synthesis of Low-Level Looping Programs

Inductive program synthesis, from input/output examples, can provide an opportunity to automatically create programs from scratch without presupposing the algorithmic form of the solution. For induction of general programs with loops (as opposed to loop-free programs, or synthesis for domain-specific languages), the state of the art is at the level of introductory programming assignments. Most problems that require algorithmic subtlety, such as fast sorting, have remained out of reach without the benefit of significant problem-specific background knowledge. A key challenge is to identify cues that are available to guide search towards correct looping programs. We present MAKESPEARE, a simple delayed-acceptance hillclimbing method that synthesizes low-level looping programs from input/output examples. During search, delayed acceptance bypasses small gains to identify significantly-improved stepping stone programs that tend to generalize and enable further progress. The method performs well on a set of established benchmarks, and succeeds on the previously unsolved “Collatz Numbers” program synthesis problem. Additional benchmarks include the problem of rapidly sorting integer arrays, in which we observe the emergence of comb sort (a Shell sort variant that is empirically fast). MAKESPEARE has also synthesized a record-setting program on one of the puzzles from the TIS100 assembly language programming game.

Interactive Semantic Parsing for If-Then Recipes via Hierarchical Reinforcement Learning

Given a text description, most existing semantic parsers synthesize a program in one shot. However, it is quite challenging to produce a correct program solely based on the description, which in reality is often ambiguous or incomplete. In this paper, we investigate interactive semantic parsing, where the agent can ask the user clarification questions to resolve ambiguities via a multi-turn dialogue, on an important type of programs called “If-Then recipes.” We develop a hierarchical reinforcement learning (HRL) based agent that significantly improves the parsing performance with minimal questions to the user. Results under both simulation and human evaluation show that our agent substantially outperforms non-interactive semantic parsers and rule-based agents.1

On the Mutual Dependence Between Formal Methods and Empirical Testing in Program Verification

This paper provides a review of Raymond Turner’s book Computational Artefacts. Towards a Philosophy of Computer Science. Focus is made on the definition of program correctness as the twofold problem of evaluating whether both the symbolic program and the physical implementation satisfy a set of specifications. The review stresses how these are not two separate problems. First, it is highlighted how formal proofs of correctness need to rely on the analysis of physical computational processes. Secondly, it is underlined how software testing requires considering the formal relations holding between the specifications and the symbolic program. Such a mutual dependency between formal and empirical program verification methods is finally shown to influence the debate on the epistemological status of computer science.

Penalty Function Method and Regularization in the Analysis of Improper Convex Programs

We consider the questions of correction of improper convex programs, first of all, problems with inconsistent systems of constraints. Such problems often arise in the practice of mathematical simulation of specific applied settings in operations research. Since improper problems are rather frequent, it is important to develop methods of their correction, i.e., methods of construction of solvable models that are close to the original problems in a certain sense. Solutions of these models are taken as generalized (approximation) solutions of the original problems. We construct the correcting problems using a variation of the right-hand sides of the constraints with respect to the minimum of a certain penalty function, which, in particular, can be taken as some norm of the vector of constraints. As a result, we obtain optimal correction methods that are modifications of the (Tikhonov) regularized method of penalty functions. Special attention is paid to the application of the exact penalty method. Convergence conditions are formulated for the proposed methods and convergence rates are established.

3-D time-dependent analysis of multilayered cross-anisotropic saturated soils based on the fractional viscoelastic model

• The fractional Merchant model is introduced to simulate the viscoelasticity of soil skeleton. • 3-D solutions for fractional viscoelastic saturated soils are obtained by the elastic-viscoelastic correspondence principle. • Time-dependent analysis of multilayered cross-anisotropic fractional viscoelastic saturated soils is carried out. The fractional Merchant viscoelastic model is introduced to simulate the viscoelasticity of soil skeleton in this study. According to the elastic-viscoelastic correspondence principle, elastic parameters including shear modulus G v , horizontal elastic modulus E h and vertical elastic modulus E v are replaced by the reciprocal of the flexibility coefficient of viscoelastic media in the Laplace transformed domain. Then, based on the precise integration solutions of multilayered cross-anisotropic elastic saturated soils, 3-D solutions of viscoelastic saturated soils are derived. The final solutions in the physical domain are obtained by the Laplace numerical inversion. The correctness of theories and programs is verified by comparing the numerical results with existing references. Sensitivity analyses are conducted to investigate the effects of viscoelastic parameters, cross-anisotropic parameters and stratification of soils on time-dependent displacement and excess pore water pressure.

Tuning lock-based multicore program based on sliding windows to tolerate data race

Because in-house debugging and test are difficult to discover all potential data races in multicore programs, it is necessary and significant to tolerate the potential data races in the production-run phase to secure the correct execution. However, the existing tolerating methods are limited to some kinds of data races. This paper proposes a new data-race tolerating approach, which can detect and adjust the data races whether it is in the protection of critical section or lack of protection to improve the correctness of multicore programs. It uses sliding windows to accommodate the memory instructions in critical section or recent memory instructions lack of protection and detects the potential data races which are more likely to cause errors. Then, by delaying the critical reversion points, data races are adjusted to reduce the probability of software failure. To implement the tolerating approach, the current multicore processor need not change its original cache coherence protocol and just adds very little hardware. Simulation results show that it brings low hardware, low bandwidth overhead, and negligible slowdown.

Measurement and analysis of modulation transfer function of digital image sensors

With the ceaseless development of technology, optical imaging systems have been extensively used in numerous different fields. As a result, verifying the performance of such systems has taken on significant importance. To test these systems, a commonly used metric is the modulation transfer function (MTF) because it reflects the spatial-frequency response of optical systems. To determine how best to measure the MTF of an image sensor, we use the slanted-knife-edge method to measure optical patterns and a black-and-white face sensor to receive patterns, following which we numerically calculate the MTF. We use the MTF of the Nyquist frequency (50 lp/mm) of an image sensor as the measured value, and the slanting angle for the slanted-knife-edge method ranges from 2° to 10°, which is known to provide accurate results. We then compare and analyze the experimental data and explore how inaccurate slanting angles affect the measured MTF. Finally, we propose a “program correction method” in which we input a corrected slanting angle into the region-of-interest program to correct for errors in the measurement of the MTF. The corrected parameters provide a more accurate measurement of the MTF of the given pattern.

Contour milling programming technology for virtual basing on a CNC machine

A new technique and an application program for automating the programming of the milling operation during virtual basing of the workpiece on the CNC machine table is presented, when precise installation of the workpiece along the coordinate axes of the machine is difficult. The solution of such a scientific and technical problem allows you to perform contour milling of parts with their arbitrary location on the table of the CNC machine with guaranteed alignment of the allowance along the forming path. The method involves the sequential implementation of three stages with parallel use of the created application program. At the first stage, an electronic copy of the part drawing is prepared, which contains the selected part and workpiece contour highlighted in different colors. Thus, the scanning provides automatic creation of digital two-dimensional arrays of geometric images necessary to solve the problem. At the second stage, the coordinates of three points of the workpiece measured by the probe on the machine are entered into the created program. Based on the entered data, the created program solves the problem of alignment of the allowance using the Gauss-Seidel method using the Hausdorff dimension. This approach allows us to obtain a quantitative estimate of the similarity of polygonal objects, which is necessary to solve the problem of minimax location of the allowance. The task is to determine the correction of the control program for two linear coordinates and one angular around the center of mass of the workpiece. At the third stage, the correction values calculated in the program are entered into the CNC rack of the machine and the processing of the contour begins. The proposed technique and the created application program were tested when processing the part contour on a VF-3 HAAS milling machine. Practical testing has shown the effectiveness of the technique, which is to ensure milling without overloading the tool and reduce the processing time during virtual basing of the workpiece

ParaSail: A Pointer-Free Pervasively-Parallel Language for Irregular Computations

ParaSail is a language specifically designed to simplify the construction of programs that make full, safe use of parallel hardware even while manipulating potentially irregular data structures. As parallel hardware has proliferated, there has been an urgent need for languages that ease the writing of correct parallel programs. ParaSail achieves these goals largely through simplification of the language, rather than by adding numerous rules. In particular, ParaSail eliminates global variables, parameter aliasing, and most significantly, re-assignable pointers. ParaSail has adopted a pointer-free approach to defining complex data structures. Rather than using pointers, ParaSail supports flexible data structuring using expandable (and shrinkable) objects implemented using region-based storage management, along with generalized indexing. By eliminating global variables, parameter aliasing, and pointers, ParaSail reduces the complexity for the programmer, while still allowing ParaSail to provide flexible, pervasive, safe, parallel programming for irregular computations. Perhaps the most interesting discovery in this language development effort, based on over six years of use by the author and a group of ParaSail users, has been that it is possible to simultaneously simplify the language, support parallel programming with advanced data structures, and maintain flexibility and efficiency.

Parametric schema inference for massive JSON datasets

In recent years, JSON established itself as a very popular data format for representing massive data collections. JSON data collections are usually schemaless. While this ensures several advantages, the absence of schema information has important negative consequences as well: Data analysts and programmers cannot exploit a schema for a reliable description of the structure of the dataset, the correctness of complex queries and programs cannot be statically checked, and many schema-based optimizations are not possible. In this paper, we deal with the problem of inferring a schema from massive JSON datasets. We first identify a JSON type language which is simple and, at the same time, expressive enough to capture irregularities and to give complete structural information about input data. We then present our contributions, which are the design of a parametric and parallelizable schema inference algorithm, its theoretical study, and its implementation based on Spark, enabling reasonable schema inference time for massive collections. Our algorithm is parametric as the analyst can specify a parameter determining the level of precision and conciseness of the inferred schema. Finally, we report about an experimental analysis showing the effectiveness of our approach in terms of execution time, conciseness of inferred schemas, and scalability.

Bounded model checking of signal temporal logic properties using syntactic separation

Signal temporal logic (STL) is a temporal logic formalism for specifying properties of continuous signals. STL is widely used for analyzing programs in cyber-physical systems (CPS) that interact with physical entities. However, existing methods for analyzing STL properties are incomplete even for bounded signals, and thus cannot guarantee the correctness of CPS programs. This paper presents a new symbolic model checking algorithm for CPS programs that is refutationally complete for general STL properties of bounded signals. To address the difficulties of dealing with an infinite state space over a continuous time domain, we first propose a syntactic separation of STL, which decomposes an STL formula into an equivalent formula so that each subformula depends only on one of the disjoint segments of a signal. Using the syntactic separation, an STL model checking problem can be reduced to the satisfiability of a first-order logic formula, which is decidable for CPS programs with polynomial dynamics using satisfiability modulo theories (SMT). Unlike the previous methods, our method can verify the correctness of CPS programs for STL properties up to given bounds.