Simula School

Abstract Teamwork is crucial in software development, particularly in agile development teams which are cross-functional and where team members work intensively together to develop a cohesive software solution. Effective teamwork is not easy; prior studies indicate challenges with communication, learning, prioritization, and leadership. Nevertheless, there is much advice available for teams, from agile methods, practitioner literature, and general studies on teamwork to a growing body of empirical studies on teamwork in the specific context of agile software development. This article presents the agile teamwork effectiveness model (ATEM) for colocated agile development teams. The model is based on evidence from focus groups, case studies, and multi-vocal literature and is a revision of a general team effectiveness model. Our model of agile teamwork effectiveness is composed of shared leadership, team orientation, redundancy, adaptability, and peer feedback. Coordinating mechanisms are needed to facilitate these components. The coordinating mechanisms are shared mental models, communication, and mutual trust. We critically examine the model and discuss extensions for very small, multi-team, distributed, and safety-critical development contexts. The model is intended for researchers, team members, coaches, and leaders in the agile community.

Sudden cardiac death is a major health problem in the industrialized world. The lethal event is typically ventricular fibrillation (VF), during which the co-ordinated regular contraction of the heart is overthrown by a state of mechanical and electrical anarchy. Understanding the excitation patterns that sustain VF is important in order to identify potential therapeutic targets. In this paper, we studied the organization of human VF by combining clinical recordings of electrical excitation patterns on the epicardial surface during in vivo human VF with simulations of VF in an anatomically and electrophysiologically detailed computational model of the human ventricles. We find both in the computational studies and in the clinical recordings that epicardial surface excitation patterns during VF contain around six rotors. Based on results from the simulated three-dimensional excitation patterns during VF, which show that the total number of electrical sources is 1.4 +/- 0.12 times greater than the number of epicardial rotors, we estimate that the total number of sources present during clinically recorded VF is 9.0 +/- 2.6. This number is approximately fivefold fewer compared with that observed during VF in dog and pig hearts, which are of comparable size to human hearts. We explain this difference by considering differences in action potential duration dynamics across these species. The simpler spatial organization of human VF has important implications for treatment and prevention of this dangerous arrhythmia. Moreover, our findings underline the need for integrated research, in which human-based clinical and computational studies complement animal research.

SUMMARY The use of search algorithms for test data generation has seen many successful results. For structural criteria like branch coverage, heuristics have been designed to help the search. The most common heuristic is the use of approach level (usually represented with an integer) to reward test cases whose executions get close (in the control flow graph) to the target branch. To solve the constraints of the predicates in the control flow graph, the branch distance is commonly employed. These two measures are linearly combined. Since the approach level is more important, the branch distance is normalized , often in the range [0, 1]. In this paper, different types of normalizing functions are analyzed. The analyses show that the one that is usually employed in the literature has several flaws. The paper presents a different normalizing function that is very simple and does not suffer from these limitations. Empirical and analytical analyses are carried out to compare these two functions. In particular, their effect is studied on commonly used search algorithms, such as Hill Climbing, Simulated Annealing and Genetic Algorithms. Copyright © 2011 John Wiley & Sons, Ltd.

Abstract Large-scale agile development has gained widespread interest in the software industry, but it is a topic with few empirical studies of practice. Development projects at scale introduce a range of new challenges in managing a large number of people and teams, often with high uncertainty about product requirements and technical solutions. The coordination of teams has been identified as one of the main challenges. This study presents a rich longitudinal explanatory case study of a very large software development programme with 10 development teams. We focus on inter-team coordination in two phases: one that applies a first-generation agile development method and another that uses a second-generation one. We identified 27 coordination mechanisms in the first phase, and 14 coordination mechanisms in the second. Based on an analysis of coordination strategies and mechanisms, we develop five propositions on how the transition from a first- to a second-generation method impacts coordination. These propositions have implications for theory and practice.

BACKGROUND: Sexual reproduction has classically been considered as a barrier to the buildup of discrete phenotypic differentiation. This notion has been confirmed by models of sympatric speciation in which a fixed genetic architecture and a linear genotype phenotype mapping were assumed. In this paper we study the influence of a flexible genetic architecture and non-linear genotype phenotype map on differentiation under sexual reproduction.We use an individual based model in which organisms have a genome containing genes and transcription factor binding sites. Mutations involve single genes or binding sites or stretches of genome. The genome codes for a regulatory network that determines the gene expression pattern and hence the phenotype of the organism, resulting in a non-linear genotype phenotype map. The organisms compete in a multi-niche environment, imposing selection for phenotypic differentiation. RESULTS: We find as a generic outcome the evolution of discrete clusters of organisms adapted to different niches, despite random mating. Organisms from different clusters are distinct on the genotypic, the network and the phenotypic level. However, the genome and network differences are constrained to a subset of the genome locations, a process we call genotypic canalization. We demonstrate how this canalization leads to an increased robustness to recombination and increasing hybrid fitness. Finally, in case of assortative mating, we explain how this canalization increases the effectiveness of assortativeness. CONCLUSION: We conclude that in case of a flexible genetic architecture and a non-linear genotype phenotype mapping, sexual reproduction does not constrain phenotypic differentiation, but instead constrains the genotypic differences underlying it. We hypothesize that, as genotypic canalization enables differentiation despite random mating and increases the effectiveness of assortative mating, sympatric speciation is more likely than is commonly suggested.

OBJECTIVES: The aim of this study was to test the association between quality of sleep and stress in individuals with TMD (temporomandibular joint dysfunction) in simulated Mars mission. METHODS: The 24 healthy crew members were recruited. The physiological measures of systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were recorded. The Symptom Checklist-90-revised was used which was based on nine dimensions of psychological functioning. The Multidimensional Pain Inventory was pain severity, social and physical activities, affective distress, social support, and feelings of life control. The Pittsburgh Sleep Quality Index was used to measure the number of hours spent in bed and during asleep, frequency and reasons for awakening, and difficulty returning to sleep after awakening. The orofacial pain questionnaire was applied to measure pain experience using descriptors from the McGill Pain Questionnaire. Salivary cortisol and melatonin were measured. RESULTS: The 15 crew members reported temporomandibular joint pain after 6 days of mission. On dental examination, 5 crew members reported simple muscle pain (SM) and other 10 crew members with TMD. The TMD group endorsed more affective descriptors of their pain experience. Compared to the TMD group, the SM group also reported significantly poorer sleep duration. The TMD group reported nonsignificantly more daytime dysfunction than the control. Higher levels of salivary cortisol and salivary melatonin were reported in the TMD group as compared to other group. CONCLUSION: This study concludes that both quality of sleep and stress levels due to extreme condition (simulated Mars mission) were associated with TMD in simulated Mars mission.

Este artigo apresenta um modelo matemático preciso de arranjo fotovoltaico que se integra facilmente a simuladores comuns da área de Eletrônica de Potência. Simulado em conjunto com conversores chaveados, permite avaliar o impacto de variações na temperatura e na radiação solar sobre a eficiência do sistema. Apresenta-se o procedimento para se ajustar o comportamento do modelo ao obtido com módulos comerciais. Resultados de simulação de uma fonte de corrente controlada por tensão, sensível às condições atmosféricas, revelaram uma característica I-V idêntica a do módulo KC200GT da Kyocera, cujos dados de catálogo foram utilizados. Esta proposta não segue a tendência de simplificar o circuito elétrico equivalente da célula fotovoltaica, uma vez que a perda de precisão é inevitável mediante tal circunstância. Mesmo assim, foi possível obter um modelo computacional de fácil e rápida implementação.

In this paper, we utilize stochastic geometry to analyze the primary service (PS) outage performance for spectrum sharing in Rayleigh fading environment. Using this approach, the impacts of the secondary service (SS) parameters and wireless environment on the PS outage probability are analyzed. We further obtain a closed form for the PS outage probability. The maximum SS transmitter node density for a given outage probability constraint of the PS is then obtained. We also investigate the impact of secondary spectrum sensing on the PS outage probability. A novel approach is further proposed that provides tight approximation for the PS outage probability. The results of the proposed approach are then validated through analysis and simulations. We then consider power control in the secondary network and show that the truncated channel inversion power control significantly decreases the PS outage probability. Cases with centralized and decentralized cooperative spectrum sensing are also studied, and their corresponding PS outage probabilities are analyzed. Mean spatial throughput of the SS is also analyzed. We further investigate the impact of the PS outage constraint on the spatial throughput of the SS. Extensive simulations confirm our analytical derivations.

SUMMARY: Ordinary differential equation models facilitate the understanding of cellular signal transduction and other biological processes. However, for large and comprehensive models, the computational cost of simulating or calibrating can be limiting. AMICI is a modular toolbox implemented in C++/Python/MATLAB that provides efficient simulation and sensitivity analysis routines tailored for scalable, gradient-based parameter estimation and uncertainty quantification. AVAILABILITYAND IMPLEMENTATION: AMICI is published under the permissive BSD-3-Clause license with source code publicly available on https://github.com/AMICI-dev/AMICI. Citeable releases are archived on Zenodo. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Leishmaniasis is a neglected pathology with a high incidence worldwide, and is a governmental health issue due to the increased morbidity and mortality associated with the disease and a scarce therapeutic arsenal. Cysteine proteases have been investigated as targets for new drugs because they are essential in the infectivity of the parasite during its interaction with the host and in its nutrition. This study aimed to identify compounds with leishmanicidal activity, by synthesis of compounds, in vitro evaluation of their biological activity and using molecular modeling and bioinformatics tools. The study of biological activity demonstrated that one compound showed inhibitory activity against the enzyme rCPB 2.8 at a concentration of 100 mol L -1 . Activation of the enzyme rCPB 2.8 by other 4 compounds was also verified, which may be related to the interaction of these compounds with an allosteric site on the enzyme.

There are many educational situations where the student learns by using a model and we are beginning to explore the benefits of using an interactive computer to give a greater understanding of the relationship between the model and the real situation, and also of the real situation. This article gives a broad introduction to applications in the field of sixth‐form science.

Objetivos: Avaliar se o treinamento realizado com o simulador cirúrgico de catarata Eyesi e o seu currículo de exercícios padrão são efetivos em melhorar o desempenho de cirurgiões de catarata em formação na confecção de capsulorrexe em cápsulas de alta tensão realizadas no simulador. Métodos: Analisamos retrospectivamente relatórios de treinamento de residentes de 2º e 3º ano e fellows de catarata que realizaram o curso versão 2.1 de treinamento com o simulador cirúrgico de catarata Eyesi no período de maio [...]

ABSTRACT Eikonal models have been widely used for traveltime computations in the field of seismic imaging, but they are often criticized for having low accuracy and poor resolution of the output image. Including amplitude information can provide higher model resolution and accuracy of the images. We have developed a new approach for computing eikonal traveltimes and amplitudes, and we implemented it for multicore computer processing unit and graphics processing unit computer architectures. Traveltimes and amplitudes are computed simultaneously in iterations of the 3D velocity model. This is achieved by extending a fast sweeping method by computing amplitudes directly after the traveltimes with upwind numerical difference schemes. By performing the extra computations simultaneously with the traveltimes, the additional cost for the amplitude and raypaths is low. We tested our method on synthetic 3D data sets to compute traveltimes, amplitudes, and raypaths, from which the Helmholtz Green’s function was assembled. Using a grid of 1243 nodes, the computations were performed in less than 1 s. The proposed method could work as a feasible alternative to full waveform modeling in seismic applications, which suffers from demanding computations because it requires several order of magnitudes shorter computing times.

Objective: The objective of this study is to investigate the thermal behavior of coated cutting tools in industrial turning processes, aiming to enhance machining efficiency and prolong tool lifespan. Theoretical Framework: The study is grounded in the concepts of heat transfer, thermally insulating coatings, and their impact on cutting tool performance. Key theories and models include thermal conductivity, thermal insulation, and heat dissipation mechanisms. Methodology: The research employs numerical simulation using the COMSOL® Multiphysics package to model transient heat transfer within coated tools and their holders. Thermal contact resistance at the tool-holder interface is also considered. Two coating configurations (Model 1 and Model 2) with different materials are analyzed, resulting in six simulation scenarios. Results and Discussion: The simulations demonstrate significant temperature reductions in the coated tools compared to uncoated ones, with Model 2 showing the most substantial decrease. These findings indicate the effectiveness of thermally insulating coatings in mitigating heat generation and improving tool performance. Research Implications: The study's findings have practical implications for the manufacturing industry, suggesting that the use of specific coatings can lead to higher cutting velocities and prolonged tool lifespan. These insights can inform decision-making in tool selection and process optimization. Originality/Value: This research contributes to the literature by providing a detailed analysis of the thermal behavior of coated cutting tools under extreme temperatures. The study's innovative approach and practical implications offer valuable insights for improving machining processes and tool performance.

a concluso deste trabalho. RESUMO Este trabalho tem como objetivo a comparao dos resultados de ensaios de durabilidade em um suporte do eixo traseiro de um veculo leve de passeio, submetido a dois tipos distintos de testes: durabilidade em rodagem real e em simuladores de estradas. Aps o trmino dos ensaios, o componente apresentou resultados diferentes: as trincas podem ser observadas na pea submetida rodagem real, e os danos no ocorrem no

The purpose of the study was to investigate effect of the experiential learning approach on junior high school pupils’ performance in finding area of plane figures. The sample size consisted of seventy (70) pupils comprising 35 in the control group and 35 in the experimental group. A quasi-experimental design was used in which the experimental group was exposed to experiential learning teaching approach and control group was taught normally using the traditional method. Pre-test and later post-test, which were based on the Ghana Education Service junior high school mathematics syllabus requirements, were carried out simultaneously on both groups before and after the experiment respectively. A focus group discussion was held with five mathematics teachers to find out the impact of the experiential learning activities on their pupils’ in performance in finding area of plane figures. An independent sample t-test analysis was carried out on the pre-test and post-test scores. The findings revealed that the experiential learning teaching approach led to better development of the pupils’ performance in the concept than the traditional method of teaching. The performance of experiential learning group was higher than the comparable traditional group. The teachers confirmed in the focus group discussion that experiential learning impact on learners’ performance in finding area of plane figures. The study recommends that teachers should incorporate experiential learning teaching approach into their lessons to help improve pupils’ conceptual understanding of area of plane figures.

O estudo consistiu no ajuste de taper para descrever o afilamento do fuste de um povoamento de mogno africano (Khaya spp.) não desbastado, localizado no norte de Minas Gerais, com o objetivo de realizar a otimização de corte das árvores para múltiplos produtos da madeira para três sítios, com a idade de corte de 15 e 20 anos. Foi ajustado a uma base de cubagem rigorosa de 469 árvores, o modelo de Kozak para cada sítio e através da integral deste modelo realizou-se a determinação do volume a partir da prognose da estrutura diamétrica de cada sítio para ambas as idades analisadas. Após esta etapa, simulou-se o corte das árvores para múltiplo produtos (laminado, compensado, madeira serrada, madeira roliça e resíduos). A partir da estimativa dos sortimentos, com valores de volume, número de toras e preço médio dos produtos realizou-se a análise financeira através do cálculo do Valor Presente Líquido Infinito (VPL∞) para as taxas de desconto de 6%, 10% e 14% ao ano. Deste modo foi possível concluir que o sítio 1 apresentou os cenários mais atrativos, sendo viável em todas as idades e taxas de desconto avaliadas. O cenário mais viável economicamente, foi o corte aos 15 anos par a taxa de 6%, com o VPL de US$ 11.511,97. Já o sítio 2 em ambas idades simuladas apresentou-se inviável economicamente somente à uma taxa de 14% ao ano. Por fim o sítio 3 apresentou VPL negativo aos 15 e 20 anos nas simulações com as taxas de 10% e 14% ao ano.

BACKGROUND AND OBJECTIVE: The MitraClip is the most widely used percutaneous treatment for mitral regurgitation, typically performed under the real-time guidance of 3D transesophageal echocardiography (TEE). However, artifacts and low image contrast in echocardiography hinder accurate clip visualization. This study presents a proof-of-concept of an automated pipeline for clip detection from 3D TEE images acquired in a controlled in vitro simulation environment. METHODS: An Attention UNet was employed to segment the device, while a DenseNet classifier predicted its configuration among ten possible states, ranging from fully closed to fully open. Based on the predicted configuration, a template model derived from computer-aided design (CAD) was automatically registered to refine the segmentation and enable quantitative characterization of the device. The pipeline was trained and validated on 196 3D TEE images acquired using a heart simulator, with ground-truth annotations refined through CAD-based templates. RESULTS: The Attention UNet achieved an average surface distance of 0.76 mm and a 95% Hausdorff distance of 2.44 mm for segmentation, while the DenseNet achieved an average weighted F1-score of 0.80 for classification. Post-refinement, segmentation accuracy improved, with average surface distance and 95% Hausdorff distance reduced to 0.69 mm and 1.83 mm, respectively. CONCLUSION: This pipeline enhanced clip visualization, providing fast and accurate detection with quantitative feedback, potentially improving procedural efficiency and reducing adverse outcomes.

El objetivo de este documento es confirmar la importancia de las prácticas profesionales y el uso de tecnología, en la formación de profesionales, y su valor coadyuvante preponderante en la inserción profesional como complemento de la formación teórica en hotelería, apoyándonos en un estudio de caso observado en la Universidad Veracruzana (en lo sucesivo citada como UV). Se tomó como muestra de este estudio de caso los estudiantes cursando la Experiencia Educativa (en lo sucesivo citado como EE), Prácticas en Gestión Hotelera en el año 2014 adscritos al Programa Educativo (en lo sucesivo citado como PE) de Administración Turística (en lo sucesivo citado como AT). La información se obtuvo mediante tres parámetros: la evaluación subjetiva del desempeño del practicante por un representante del hotel anfitrión a través de un formulario de preguntas cerradas y abiertas; la evaluación objetiva de los resultados alcanzados por un grupo muestra de estudiantes participando en un concurso internacional con el uso de simuladores; y la opinión subjetiva recabada entre egresados participantes de los beneficios de cumplir con un programa de prácticas profesionales y el uso de simuladores.

Penyakit Tuberkulosis (TB) disebabkan karena bakteri mycrobacterium tuberculosis dan merupakan penyakit menular yang mempengaruhi paru-paru. Di Kalimantan Barat tercatat jumlah kasus baru TB sebanyak 3.463 kasus dengan angka insidens 70, 21 per 100.000 penduduk. Sedangkan dengan persentase kesembuhan 67, 5% pasien TB paru dinyatakan sembuh, dengan rincian dari 3611 pasien yang mendapatkan pengobatan, sebanyak 2436 pasien yang sembuh. Dengan pemberian vaksinasi dan pengobatan penularan penyakit TB dapat dicegah. Pada penelitian ini, model epidemi dibagi menjadi tiga subpopulasi, yaitu subpopulasi Susceptible (S), subpopulasi Infectious (I) dan subpopulasi Recovered (R). Dari ketiga subpopulasi tersebut kemudian dibentuk model epidemi tipe SIR. Untuk menekan penularan, sistem diberikan kontrol, yaitu vaksinasi (u1) pada bayi yang baru lahir dan kontrol pengobatan (u2) diberikan pada individu infective yang melakukan kontak langsung dengan individu susceptible. Tujuan pemberian kontrol tersebut adalah untuk mengurangi jumlah individu susceptible dan individu infective. Model epidemi SIR yang sudah diberikan kontrol (u1) dan (u2), diselesaikan dengan Prinsip Minimum Pontryagin untuk mendapatkan suatu kontrol optimal u ∗ 1 dan u ∗ 2 . Berdasarkan simulasi numerik yang telah dilakukan didapatkan hasil yaitu kontrol bekerja secara efektif dalam menekan penyebaran TB sehingga individu infective berkurang.Kata Kunci: Tuberkulosis, Model SIR, Kontrol Optimal, Prinsip Minimum Pontryagin