Lightweight Formal Verification in Classroom Instruction of Reasoning about Functional Code

In college courses dealing with material that requires mathematical rigor, the adoption of a machine-readable representation for formal arguments can be advantageous. Students can focus on a specific collection of constructs that are represented consistently. Examples and counterexamples can be evaluated. Assignments can be assembled and checked with the help of an automated formal reasoning system. However, usability and accessibility do not have a high priority and are not addressed sufficiently well in the design of many existing machine-readable representations and corresponding formal reasoning systems. In earlier work [Lap09], we attempt to address this broad problem by proposing several specific design criteria organized around the notion of a natural context: the sphere of awareness a working human user maintains of the relevant constructs, arguments, experiences, and background materials necessary to accomplish the task at hand. We report on our attempt to evaluate our proposed design criteria by deploying within the classroom a lightweight formal verification system designed according to these criteria. The lightweight formal verification system was used within the instruction of a common application of formal reasoning: proving by induction formal propositions about functional code. We present all of the formal reasoning examples and assignments considered during this deployment, most of which are drawn directly from an introductory text on functional programming. We demonstrate how the design of the system improves the effectiveness and understandability of the examples, and how it aids in the instruction of basic formal reasoning techniques. We make brief remarks about the practical and administrative implications of the system’s design from the perspectives of the student, the instructor, and the grader.

Efficient Support for Common Relations in Lightweight Formal Reasoning Systems

In work that involves mathematical rigor, there are numerous benefits to adopting a representation of models and arguments that can be supplied to a formal reasoning or verification system: reusability, automatic evaluation of examples, and verification of consistency and correctness. However, accessibility has not been a priority in the design of formal verification tools that can provide these benefits. In earlier work [Lap09a], we attempt to address this broad problem by proposing several specific design criteria organized around the notion of a natural context: the sphere of awareness a working human user maintains of the relevant constructs, arguments, experiences, and background materials necessary to accomplish the task at hand. This work expands one aspect of the earlier work by considering more extensively an essential capability for any formal reasoning system whose design is oriented around simulating the natural context: native support for a collection of mathematical relations that deal with common constructs in arithmetic and set theory. We provide a formal definition for a context of relations that can be used to both validate and assist formal reasoning activities. We provide a proof that any algorithm that implements this formal structure faithfully will necessary converge. Finally, we consider the efficiency of an implementation of this formal structure that leverages modular implementations of well-known data structures: balanced search trees and transitive closures of hypergraphs.

Deconstruction plan assessment using multi-criteria decision-making methods

The purpose of this paper is to present two multi-criteria decision-making models, including an Analytic Hierarchy Process (AHP) model and an Analytic Network Process (ANP) model for the assessment of deconstruction plans and to make a comparison between the two models with an experimental case study. Deconstruction planning is under pressure to reduce operation costs, adverse environmental impacts and duration, in the meanwhile to improve productivity and safety in accordance with structure characteristics, site conditions and past experiences. To achieve these targets in deconstruction projects, there is an impending need to develop a formal procedure for contractors to select a most appropriate deconstruction plan. Because numbers of factors influence the selection of deconstruction techniques, engineers definitely need effective tools to conduct the selection process. In this regard, multi-criteria decision-making methods such as AHP have been adopted to effectively support deconstruction technique selection in previous researches. in which it has been proved that AHP method can help decision-makers to make informed decisions on deconstruction technique selection based on a sound technical framework. In this paper, the authors present the application and comparison of two decision-making models including the AHP model and the ANP model for deconstruction plan assessment. The paper concludes that both AHP and ANP are viable and capable tools for deconstruction plan assessment under the same set of evaluation criteria. However, although the ANP can measure relationship among selection criteria and their sub-criteria, which is normally ignored in the AHP, the authors also indicate that whether the ANP model can provide a more accurate result should be examined in further research.

Formal validation of automated policy refinement in the management of network security systems

Policy hierarchies and automated policy refinement are powerful approaches to simplify administration of security services in complex network environments. A crucial issue for the practical use of these approaches is to ensure the validity of the policy hierarchy, i.e. since the policy sets for the lower levels are automatically derived from the abstract policies (defined by the modeller), we must be sure that the derived policies uphold the high-level ones. This paper builds upon previous work on Model-based Management, particularly on the Diagram of Abstract Subsystems approach, and goes further to propose a formal validation approach for the policy hierarchies yielded by the automated policy refinement process. We establish general validation conditions for a multi-layered policy model, i.e. necessary and sufficient conditions that a policy hierarchy must satisfy so that the lower-level policy sets are valid refinements of the higher-level policies according to the criteria of consistency and completeness. Relying upon the validation conditions and upon axioms about the model representativeness, two theorems are proved to ensure compliance between the resulting system behaviour and the abstract policies that are modelled.

Outorga onerosa do direito de construir e dinâmica do mercado imobiliário formal: planejamento e descaminhos na expansão urbana de Parnamirim RN (2008-2010)

The `Outorga Onerosa do Direito de Construir - OODC` (Public Concession of Building Rights), instrument instituted by The City Statute in 2001, has as main objective the recovery of urban property, seeking for a fair distribution the urbanization benefits. The possibility of usage of the OODC instrument is linked to the maximum utilization coefficient, determined to specific areas in accordance to existing infrastructure conditions, further taking into account the formal real estate market, expansion axis and crowding. Being an instrument which establishes values to be paid for a better use of land, it maintains a narrow relation to the real estate, incentivizing or discouraging the crowding in specific areas. The present study investigates the relationship between the criteria for the making of the Public Concession of Building Rights instrument and the dynamics of the formal real estate market. It takes as empiric universe Parnamirim (RN), part of the Natal Metropolitan Area (RN), focusing on the application of the OODC in the period of 2008-2010. It seeks to better understand the necessary basis for the formulation of the instrument, about how it works and its relation to the formal real estate market. It aims to depict the formal real estate market by presenting the production of urban space in Parnamirim in terms of intensity and nature of the real estate, furthermore identifying the licensed properties through the application of the municipality instrument. For the conclusion, it is discussed the criteria for the formation of OODC, its relationship to the dynamics of the formal real estate market and its influencing possibilities in the processes of usage and occupation of land in the context of urban planning

Educação ambiental: mediações sociais e políticas e a indolência do Poder Público à sua inclusão no ensino formal

As a result of the prediction of irreversible changes on necessary conditions to maintain life, including human, on the planet, environmental education got the spotlight in the political scenario, due to social pressure for the development of individual and collective values, knowledge, skills, attitudes and competences towards environmental preservation. In Brazil, only in 1999 the right for environmental education was officially granted to people, having the status of essential and permanent component in the country s education. Since then, it has been Government s duty, in each federal branch, to plan actions to make it happen, in an articulate way in all levels and modalities of the education process, both formally and informally. This work of research has environmental education in the school as subject matter, and aims on analyzing social and political mediations established between this National Environmental Education policy and the contexts associated to the legislative production process, the political nature of the conceptions about environmental education that underlie Law 9.795/99 (Brazil, 2009c) and also Rio Grande do Norte Government s actions and omissions related to the imperative nature of the insertion of environmental education in the schools ran by the state, during the ten years this law has been in force. The investigation of the subject matter was led by a social and historical understanding of the social and environmental phenomena, as well as of the education system as a whole, considering that only through a dialectical view we can see the real world, by destroying the pseudo-concreteness that surrounds the topic. While analyzing, we assumed that in face of the dominance of a social organization in which market regulations rule on environmental ones, by developing individual and collective critical conscience, environmental education can become a threat to dominant economical interests in exploiting natural resources. The results of this research suggest that as an educational practice to be developed in an integrated, continuous and permanent fashion in all levels and modalities of formal education, environmental education has not yet come to pass in the state of Rio Grande do Norte, due to the neglect and disrespect of the government when facing the need of promoting the necessary and legally appointed measures to make it present in the basic education provided by the state. The legislators silence when it comes to approving a regulation on environmental education essential to define policies, rules and criteria to teaching the subject in the state and the omission from the public administration regarding critical actions in order to integrate in public schools the activities related to the National Environmental Education Policy, represent a political decision for not doing anything, despite the legal demand for an active position. This neglecting attitude for the actualizing of strategically concrete actions, urgent and properly planned for the implementation of environmental education in schools in a multidisciplinary way, exposes the lack of interest the predominant classes have in such kind of education being made available, as it could be developed based on a critic political view, becoming a political and educational action against dominance. When analyzing the basic principles and fundamental goals in Law 9.795/99 (Brazil, 2009c) the development of a critic environmental education is really possible and concurs with the National Environmental Education Policy, reflecting the social and political mediations established between this public policy and the contexts associated to its legislative production process, which are responsible for approving a regulation which also represents the mind of the people about environmental protection above anything else

Are supplier selection criteria going green? Case studies of companies in Brazil

Purpose - The purpose of this paper is to verify if Brazilian companies are adopting environmental requirements in the supplier selection process. Further, this paper intends to analyze whether there is a relation between the level of environmental management maturity and the inclusion of environmental criteria in the companies' selection of suppliers.Design/methodology/approach - A review of mainstream literature on environmental management, traditional criteria in the supplier selection process and the incorporation of environmental requirements in this context. The empirical study's strategy is based on five Brazilian case studies with industrial companies. Face-to-face interviews and informal conversations are to be held, explanations made by e-mail with representatives from the purchasing, environmental management, logistics and other areas, and observation and the collection of company documents are also employed.Findings - Based on the cases, it is concluded that companies still use traditional criteria to select suppliers, such as quality and cost, and do not adopt environmental requirements in the supplier selection process in a uniform manner. Evidence found shows that the level of environmental management maturity influences the depth with which companies adopt environmental criteria when selecting suppliers. Thus, a company with more advanced environmental management adopts more formal procedures for selecting environmentally appropriate suppliers than others.Originality/value - This is the first known study to verify if Brazilian companies are adopting environmental requirements in the supplier selection process.

Aplicação do método B ao projeto formal de software embarcado

This work shows a project method proposed to design and build software components from the software functional m del up to assembly code level in a rigorous fashion. This method is based on the B method, which was developed with support and interest of British Petroleum (BP). One goal of this methodology is to contribute to solve an important problem, known as The Verifying Compiler. Besides, this work describes a formal model of Z80 microcontroller and a real system of petroleum area. To achieve this goal, the formal model of Z80 was developed and documented, as it is one key component for the verification upto the assembly level. In order to improve the mentioned methodology, it was applied on a petroleum production test system, which is presented in this work. Part of this technique is performed manually. However, almost of these activities can be automated by a specific compiler. To build such compiler, the formal modelling of microcontroller and modelling of production test system should provide relevant knowledge and experiences to the design of a new compiler. In ummary, this work should improve the viability of one of the most stringent criteria for formal verification: speeding up the verification process, reducing design time and increasing the quality and reliability of the product of the final software. All these qualities are very important for systems that involve serious risks or in need of a high confidence, which is very common in the petroleum industry

Definition and diagnostic criteria of sleep-related hypermotor epilepsy

The syndrome known as nocturnal frontal lobe epilepsy is recognized worldwide and has been studied in a wide range of clinical and scientific settings (epilepsy, sleep medicine, neurosurgery, pediatric neurology, epidemiology, genetics). Though uncommon, it is of considerable interest to practicing neurologists because of complexity in differential diagnosis from more common, benign sleep disorders such as parasomnias, or other disorders like psychogenic nonepileptic seizures. Moreover, misdiagnosis can have substantial adverse consequences on patients' lives. At present, there is no consensus definition of this disorder and disagreement persists about its core electroclinical features and the spectrum of etiologies involved. To improve the definition of the disorder and establish diagnostic criteria with levels of certainty, a consensus conference using formal recommended methodology was held in Bologna in September 2014. It was recommended that the name be changed to sleep-related hypermotor epilepsy (SHE), reflecting evidence that the attacks are associated with sleep rather than time of day, the seizures may arise from extrafrontal sites, and the motor aspects of the seizures are characteristic. The etiology may be genetic or due to structural pathology, but in most cases remains unknown. Diagnostic criteria were developed with 3 levels of certainty: witnessed (possible) SHE, video-documented (clinical) SHE, and video-EEG-documented (confirmed) SHE. The main research gaps involve epidemiology, pathophysiology, treatment, and prognosis.

OMERACT-OARSI Initiative: Osteoarthritis Research Society International set of responder criteria for osteoarthritis clinical trials revisited.

Background: The OARSI Standing Committee for Clinical Trials Response Criteria Initiative had developed two sets of responder criteria to present the results of changes after treatment in three symptomatic domains (pain, function, and patient's global assessment) as a single variable for clinical trials (1). For each domain, a response was defined by both a relative and an absolute change, with different cut-offs with regard to the drug, the route of administration and the OA localization. Objective: To propose a simplified set of responder criteria with a similar cut-off, whatever the drug, the route or the OA localization. Methods: Data driven approach: (1) Two databases were considered The 'elaboration' database with which the formal OARSI sets of responder criteria were elaborated and The 'revisit' database. (2) Six different scenarios were evaluated: The two formal OARSI sets of criteria Four proposed scenarios of simplified sets of criteria Data from clinical randomized blinded placebo controlled trials were used to evaluate the performances of the two formal scenarios with two different databases ('elaboration' versus 'revisit') and those of the four proposed simplified scenarios within the 'revisit' database. The placebo effect, active effect, treatment effect, and the required sample arm size to obtain the placebo effect and the active treatment effect observed were the performances evaluated for each of the six scenarios. Experts' opinion approach: Results were discussed among the participants of the OMERACT VI meeting, who voted to select the definite OMERACT-OARSI set of criteria (one of the six evaluated scenarios). Results: Data driven approach: Fourteen trials totaling 1886 CA patients and fifteen studies involving 8164 CA patients were evaluated in the 'elaboration' and the 'revisit' databases respectively. The variability of the performances observed in the 'revisit' database when using the different simplified scenarios was similar to that observed between the two databases ('elaboration' versus 'revisit') when using the formal scenarios. The treatment effect and the required sample arm size were similar for each set of criteria. Experts' opinion approach: According to the experts, these two previous performances were the most important of an optimal set of responder criteria. They chose the set of criteria considering both pain and function as evaluation domain and requiring an absolute change and a relative change from baseline to define a response, with similar cut-offs whatever the drug, the route of administration or the CA localization. Conclusion: This data driven and experts' opinion approach is the basis for proposing an optimal simplified set of responder criteria for CA clinical trials. Other studies, using other sets of CA patients, are required in order to further validate this proposed OMERACT - OARSI set of criteria. (C) 2004 OsteoArthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Forecasting stock returns using model-selection criteria

This paper examines the economic significance of return predictability in Australian equities. In light of considerable model uncertainty, formal model-selection criteria are used to choose a specification for the predictive model. A portfolio-switching strategy is implemented according to model predictions. Relative to a buy-and-hold market investment, the returns to the portfolio-switching strategy are impressive under several model-selection criteria, even after accounting for transaction costs. However, as these findings are not robust across other model-selection criteria examined, it is difficult to conclude that the degree of return predictability is economically significant.

The derivation and application of risk tolerability criteria

This research involves a study of the questions, "what is considered safe", how are safety levels defined or decided, and according to whom. Tolerable or acceptable risk questions raise various issues: about values and assumptions inherent in such levels; about decision-making frameworks at the highest level of policy making as well as on the individual level; and about the suitability and competency of decision-makers to decide and to communicate their decisions. The wide-ranging topics covering philosophical and practical concerns examined in the literature review reveal the multi-disciplined scope of this research. To support this theoretical study empirical research was undertaken at the European Space Research and Technology Centre (ESTEC) of the European Space Agency (ESA). ESTEC is a large, multi-nationality, high technology organisation which presented an ideal case study for exploring how decisions are made with respect to safety from a personal as well as organisational aspect. A qualitative methodology was employed to gather, analyse and report the findings of this research. Significant findings reveal how experts perceive risks and the prevalence of informal decision-making processes partly due to the inadequacy of formal methods for deciding risk tolerability. In the field of occupational health and safety, this research has highlighted the importance and need for criteria to decide whether a risk is great enough to warrant attention in setting standards and priorities for risk control and resources. From a wider perspective and with the recognition that risk is an inherent part of life, the establishment of tolerability risk levels can be viewed as cornerstones indicating our progress, expectations and values, of life and work, in an increasingly litigious, knowledgeable and global society.

About the Multi Criteria Ranging Problem in the Fuzzy Environment

Decision making and technical decision analysis demand computer-aided techniques and therefore more and more support by formal techniques. In recent years fuzzy decision analysis and related techniques gained importance as an efficient method for planning and optimization applications in fields like production planning, financial and economical modeling and forecasting or classification. It is also known, that the hierarchical modeling of the situation is one of the most popular modeling method. It is shown, how to use the fuzzy hierarchical model in complex with other methods of Multiple Criteria Decision Making. We propose a novel approach to overcome the inherent limitations of Hierarchical Methods by exploiting multiple criteria decision making.

Outorga onerosa do direito de construir e dinâmica do mercado imobiliário formal: planejamento e descaminhos na expansão urbana de Parnamirim RN (2008-2010)

The `Outorga Onerosa do Direito de Construir - OODC` (Public Concession of Building Rights), instrument instituted by The City Statute in 2001, has as main objective the recovery of urban property, seeking for a fair distribution the urbanization benefits. The possibility of usage of the OODC instrument is linked to the maximum utilization coefficient, determined to specific areas in accordance to existing infrastructure conditions, further taking into account the formal real estate market, expansion axis and crowding. Being an instrument which establishes values to be paid for a better use of land, it maintains a narrow relation to the real estate, incentivizing or discouraging the crowding in specific areas. The present study investigates the relationship between the criteria for the making of the Public Concession of Building Rights instrument and the dynamics of the formal real estate market. It takes as empiric universe Parnamirim (RN), part of the Natal Metropolitan Area (RN), focusing on the application of the OODC in the period of 2008-2010. It seeks to better understand the necessary basis for the formulation of the instrument, about how it works and its relation to the formal real estate market. It aims to depict the formal real estate market by presenting the production of urban space in Parnamirim in terms of intensity and nature of the real estate, furthermore identifying the licensed properties through the application of the municipality instrument. For the conclusion, it is discussed the criteria for the formation of OODC, its relationship to the dynamics of the formal real estate market and its influencing possibilities in the processes of usage and occupation of land in the context of urban planning

Outorga onerosa do direito de construir e dinâmica do mercado imobiliário formal: planejamento e descaminhos na expansão urbana de Parnamirim RN (2008-2010)

The `Outorga Onerosa do Direito de Construir - OODC` (Public Concession of Building Rights), instrument instituted by The City Statute in 2001, has as main objective the recovery of urban property, seeking for a fair distribution the urbanization benefits. The possibility of usage of the OODC instrument is linked to the maximum utilization coefficient, determined to specific areas in accordance to existing infrastructure conditions, further taking into account the formal real estate market, expansion axis and crowding. Being an instrument which establishes values to be paid for a better use of land, it maintains a narrow relation to the real estate, incentivizing or discouraging the crowding in specific areas. The present study investigates the relationship between the criteria for the making of the Public Concession of Building Rights instrument and the dynamics of the formal real estate market. It takes as empiric universe Parnamirim (RN), part of the Natal Metropolitan Area (RN), focusing on the application of the OODC in the period of 2008-2010. It seeks to better understand the necessary basis for the formulation of the instrument, about how it works and its relation to the formal real estate market. It aims to depict the formal real estate market by presenting the production of urban space in Parnamirim in terms of intensity and nature of the real estate, furthermore identifying the licensed properties through the application of the municipality instrument. For the conclusion, it is discussed the criteria for the formation of OODC, its relationship to the dynamics of the formal real estate market and its influencing possibilities in the processes of usage and occupation of land in the context of urban planning