CPS transformation with affine types for call-by-value implicit polymorphism

Transformation of programs into continuation-passing style (CPS) reveals the notion of continuations, enabling many applications such as control operators and intermediate representations in compilers. Although type preservation makes CPS transformation more beneficial, achieving type-preserving CPS transformation for implicit polymorphism with call-by-value (CBV) semantics is known to be challenging. We identify the difficulty in the problem that we call scope intrusion. To address this problem, we propose a new CPS target language Λ open that supports two additional constructs for polymorphism: one only binds and the other only generalizes type variables. Unfortunately, their unrestricted use makes Λ open unsafe due to undesired generalization of type variables. We thus equip Λ open with affine types to allow only the type-safe generalization. We then define a CPS transformation from Curry-style CBV System F to type-safe Λ open and prove that the transformation is meaning and type preserving. We also study parametricity of Λ open as it is a fundamental property of polymorphic languages and plays a key role in applications of CPS transformation. To establish parametricity, we construct a parametric, step-indexed Kripke logical relation for Λ open and prove that it satisfies the Fundamental Property as well as soundness with respect to contextual equivalence.

Pest Control in Primary Sector: Towards the Identification of Knowledge Gaps

Pest control provides important and useful services in rural and urban environments, activities, and value chains. Despite the significance of them, under operational, environmental and food security and safety terms, there are still gaps in the awareness level of targeted groups. Therefore, in the current work, we have carried out questionnaire-based surveillance to pest control operators in Greece and Cyprus, in an attempt to illustrate their knowledge regarding pest control in conjunction with demographic characteristics. In this context, the results underlined the need for further training in all aspects of pest control, but also relative activities that are often are operated by pest controllers, such as food safety activities and applications in the urban and sub-urban environment. The replies that had been obtained during the survey showed good correlations of knowledge with specific variables, such as the size of the company, the age group, and the educational background, in conjunction with the country in which the professional activities are carried out. To our knowledge, this is the first work of its kind, in terms of pest controllers’ perceptions and self-evaluation, illustrating specific knowledge gaps that have to be alleviated towards improved services in urban pest control, especially in sensitive urban areas and facilities, and improved measures for safety during the applications.

Evaluating a training intervention for improving alignment between emergency medical telephone operators and callers: a pilot study of communication behaviours

Background Calls to emergency medical lines are an essential component in the chain of survival. Operators make critical decisions based on information they elicit from callers. Although smooth cooperation is necessary, the field lacks evidence-based guidelines for how to achieve it while adhering to strict parameters of index-driven questioning. We aimed to evaluate the effect of a training intervention for emergency medical operators at a call centre in Tønsberg, Norway. The course was designed to enhance operators’ communication skills for smoothing cooperation with callers. Methods Calls were analyzed using inductively developed coding based on the course rationale and content. To evaluate whether the course generated consolidated behavioral change in everyday practice, the independent analyst evaluated 32 calls, selected randomly from eight operators, two calls before and two after course completion. To measure whether skill attainment delayed decision making, we compared the time to the first decision logged by intervention operators to eight control operators. Analysis included 3034 calls: 1375 to intervention operators (T1 = 815; T2 = 560) and 1659 to control operators (T1 = 683; T2 = 976). Results Operators demonstrated improved behaviours on how they greeted the caller (p < .001), acknowledged the caller (p < .001), and displayed empathy (p = 0.015). No change was found in the use of open-ended questions and agreeing with the caller. Contrary to expectations, operators who took the course logged first decisions more quickly than the control group (p < .001). Conclusions This pilot study demonstrated that the training intervention generated behavioural change in these operators, providing justification for scaling up the intervention.

Evaluating Situation Assessment in Distributed Network Electricity Control

Situation assessment is a critical skill amongst electricity distribution controllers but can be difficult to assess in practice. In the present research, we adapted a psychometric approach based on the principle that expert situation assessment engages cue-based associations from memory. Using consortium norming, we acquired performance data from 320 network control operators for five network control-related tasks that comprised the electricity network service provider edition of the EXPERT Intensive Skills Evaluation (EXPERTise 2.0) software. Operators were distributed across 11 Distributed Network Service Providers (DNSP), with data collected over three phases. Data were examined across the three phases of data collection and suggest that DNSPs can monitor the situation assessment of network controllers at an individual and at an organisational level, affording the opportunity to identify changes in performance and implement remedial strategies as appropriate.

Experimental ergonomic investigation of selection of the technical means for managing the dialogue of the operator with computer technology in a shipboard automated control system (ACS)

The description and results of experimental studies of rationality of using various computer control tools for the practice of developing a human-machine interface intended for automated workstations of system control operators for shipboard technical complexes are presented in the work.

Experimental ergonomic investigation of selection of the technical means for managing the dialogue of the operator with computer technology in a shipboard automated control system (ACS)

The description and results of experimental studies of rationality of using various computer control tools for the practice of developing a human-machine interface intended for automated workstations of system control operators for shipboard technical complexes are presented in the work.