Bug Localization in Model-Based Systems in the Wild

The companies that have adopted the Model-Driven Engineering (MDE) paradigm have the advantage of working at a high level of abstraction. Nevertheless, they have the disadvantage of the lack of tools available to perform bug localization at the model level. In addition, in an MDE context, a bug can be related to different MDE artefacts, such as design-time models, model transformations, or run-time models. Starting the bug localization in the wrong place or with the wrong tool can lead to a result that is unsatisfactory. We evaluate how to apply the existing model-based approaches in order to mitigate the effect of starting the localization in the wrong place. We also take into account that software engineers can refine the results at different stages. In our evaluation, we compare different combinations of the application of bug localization approaches and human refinement. The combination of our approaches plus manual refinement obtains the best results. We performed a statistical analysis to provide evidence of the significance of the results. The conclusions obtained from this evaluation are: humans have to be involved at the right time in the process (or results can even get worse), and artefact-independence can be achieved without worsening the results.

Optical soliton in a one-dimensional array of a metal nanoparticle-microcavity complex (2021 Commun. Theor. Phys. 73 115105)

During the production process an error was introduced into equation (14). The absolute value symbol was moved to the wrong place. Here, we give the correct version of equation (14) ：

Something is in the wrong place.

Inferior vena cava filter (IVCF) embolization is not uncommon and can reach 11,8%. However, device migration to the heart is not frequent and occurs in cases after IVCF fracture. We show the case of a young woman who was submitted to an unremarkable IVCF placement three days before and presented with hemodynamic instability. Since the device was not retrievable, the surgical team opted for an open cardiac surgery under cardiopulmonary bypass to remove IVCF.

Wrong place, wrong time: Children’s sensitivity to present tense spelling conventions

Spelling has been found to be influenced by the frequency with which certain orthographic patterns occur. We examined whether Grades 2–5 children were already sensitive to orthographic frequency in spelling present tense verb inflections that sound the same but are spelled differently. Children were asked to spell present tenses in two homophonous forms; both inflections are pronounced with final /t/ but are spelled with final -d (“ik vind,” I find) or -dt (“hij/zij vindt,” he/she finds). Previous research has shown that adolescents and adults make inflection errors based on the relative frequency within a pair; as “vind’ is more frequent than “vindt,” “vind” is often used incorrectly. The children showed low correct scores for third person singular spellings, and overall better performance for -d dominant verbs. Surprisingly, they did make errors related to homophone inflection but in the wrong place, marking the wrong time: homophone-based errors occurred in present tense non-homophone verbs and in past tenses. We take our findings to mean that the children were not sensitive to homophone dominance. Furthermore, the findings illustrate the importance of specific graphotactic patterns in literacy development and call for attention to these patterns in models and teaching of spelling.

Main Challenges of Teaching the Chinese Particle了 to Russian-speaking Students at Elementary Level

The particle 了 is a commonly used word in the Chinese language. Since the particle 了 is a structure word, it does not carry any semantic meaning, but it has many grammatical meanings and is used in a variety of ways. Due to the large number of its grammatical meanings and complexity of its grammatical functions, it poses certain challenges for both teachers when explaining the material and students when using it. This especially concerns Russian-speaking students due to significant differences in the grammar of Russian and Chinese. This article examines several classifications of the particle 了, described in Chinese and Russian textbooks and focuses on grammatical features of the particle 了 depending on its position in the middle and at the end of the sentence, as well as its simultaneous use of both in the middle and at the end of the sentence. The article also describes the particle’s main grammatical meanings, such as: completeness of an action, change of an action or a situation, emphasis on something, duration of an action, a way of expressing tact, and a few others. The authors analyze the most common mistakes made by Russian-speaking elementary level students when using the particle, basing their analysis on many years of their teaching experience. Among the mistakes, they highlight such as excessive use, insufficient use, and use of the particle 了 in the wrong place. Excessive use includes mistakes such using the particle 了 in negative sentences with the adverb 没, in an objective description of past events, facts, or in characteristic judgments and descriptions; with verbs followed by a predicative object; after the first verb in a sequential sentence; with verbs showing an action of a constant or repetitive nature, as well as in various constructions which exclude its use. Insufficient use includes mistakes when learners construct incomplete sentences without the 了 particle in cases where its use is required for correct meaning or for a grammatically correct construction. Mistakes where the particle 了 is used in the wrong place occur if students do not understand the specifics of verb connections in the sentence.