136 research outputs found

    Introductory programming: a systematic literature review

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    As computing becomes a mainstream discipline embedded in the school curriculum and acts as an enabler for an increasing range of academic disciplines in higher education, the literature on introductory programming is growing. Although there have been several reviews that focus on specific aspects of introductory programming, there has been no broad overview of the literature exploring recent trends across the breadth of introductory programming. This paper is the report of an ITiCSE working group that conducted a systematic review in order to gain an overview of the introductory programming literature. Partitioning the literature into papers addressing the student, teaching, the curriculum, and assessment, we explore trends, highlight advances in knowledge over the past 15 years, and indicate possible directions for future research

    EmbryoGenetics

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    The science of human genetics has advanced at an exponential pace since the double-helix structure of DNA was identified in 1953. Within only 25 years of that discovery, the first gene was sequenced. Subsequent efforts in the span of a few decades have brought advanced next-generation sequencing and new tools for genome editing, allowing scientists to write and rewrite the code of life. We are now realizing that genetics represents yet another system of information technology that follows Moore’s law, stating that computer processing power roughly doubles every two years. Importantly, with such rapid and sophisticated advancements, any tools or studies applicable to adult genetics can now also be applied to embryos.Genetic disorders affect 1% of live births and are responsible for 20% of pediatric hospitalizations and 20% of infant mortality. Many disorders are caused by recessive or X-linked genetic mutations carried by 85% of humans. Because assisted reproduction has armed us with technologies like in vitro fertilization that provide access to human embryos, we began to screen some genetic diseases simply by selecting sex. The first live births following preimplantation genetic testing (PGT) to identify sex in X-linked disease were reported by Alan Handyside in 1990. This groundbreaking work used the identification of male embryos and selective transfer of unaffected normal or carrier females as proof-of-concept to avoid genetic diseases, paving the way to extend the concept to PGT for monogenic diseases (PGT-M), including Mendelian single-gene defects (autosomal dominant/recessive, X-linked dominant/recessive), severe childhood lethality or early-onset disease, cancer predisposition, and HLA typing for histocompatible cord-blood stem cells’ transplantation. Later, we moved onto the identification and selection of euploid embryos by analysing all 23 pairs of chromosomes in 4–8 cells from the trophectoderm, called PGT for aneuploidy (PGT-A). PGT-A currently leverages next-generation sequencing technologies to uncover meiotic- and mitotic-origin aneuploidies affecting whole chromosomes, as well as duplications/deletions of small chromosome regions. A step forward was the use of structural chromosome rearrangements (PGT-SR) to identify Robertsonian and reciprocal translocations, inversions, and balanced vs. unbalanced rearrangements. Another advancement came with PGT for polygenic risk scoring (PGT-P). This technique takes us from learning how to read simple words to starting to understand poetry (i.e., evolving from PGT-M/A/SR to PGT-P for multifactorial, polygenic risk prediction). Moreover, we are moving from embryo selection to intervention because the genetic code is not only readable, but also re-writeable. Indeed, gene editing is now possible using tools like CRISPR/Cas9, which are applicable to all species, including human embryos

    Evaluation of HoloLens Tracking and Depth Sensing for Indoor Mapping Applications

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    The Microsoft HoloLens is a head-worn mobile augmented reality device that is capable of mapping its direct environment in real-time as triangle meshes and localize itself within these three-dimensional meshes simultaneously. The device is equipped with a variety of sensors including four tracking cameras and a time-of-flight (ToF) range camera. Sensor images and their poses estimated by the built-in tracking system can be accessed by the user. This makes the HoloLens potentially interesting as an indoor mapping device. In this paper, we introduce the different sensors of the device and evaluate the complete system in respect of the task of mapping indoor environments. The overall quality of such a system depends mainly on the quality of the depth sensor together with its associated pose derived from the tracking system. For this purpose, we first evaluate the performance of the HoloLens depth sensor and its tracking system separately. Finally, we evaluate the overall system regarding its capability for mapping multi-room environments

    Proceedings of the 1st Doctoral Consortium at the European Conference on Artificial Intelligence (DC-ECAI 2020)

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    1st Doctoral Consortium at the European Conference on Artificial Intelligence (DC-ECAI 2020), 29-30 August, 2020 Santiago de Compostela, SpainThe DC-ECAI 2020 provides a unique opportunity for PhD students, who are close to finishing their doctorate research, to interact with experienced researchers in the field. Senior members of the community are assigned as mentors for each group of students based on the student’s research or similarity of research interests. The DC-ECAI 2020, which is held virtually this year, allows students from all over the world to present their research and discuss their ongoing research and career plans with their mentor, to do networking with other participants, and to receive training and mentoring about career planning and career option

    Supporting the grow-and-prune model for evolving software product lines

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    207 p.Software Product Lines (SPLs) aim at supporting the development of a whole family of software products through a systematic reuse of shared assets. To this end, SPL development is separated into two interrelated processes: (1) domain engineering (DE), where the scope and variability of the system is defined and reusable core-assets are developed; and (2) application engineering (AE), where products are derived by selecting core assets and resolving variability. Evolution in SPLs is considered to be more challenging than in traditional systems, as both core-assets and products need to co-evolve. The so-called grow-and-prune model has proven great flexibility to incrementally evolve an SPL by letting the products grow, and later prune the product functionalities deemed useful by refactoring and merging them back to the reusable SPL core-asset base. This Thesis aims at supporting the grow-and-prune model as for initiating and enacting the pruning. Initiating the pruning requires SPL engineers to conduct customization analysis, i.e. analyzing how products have changed the core-assets. Customization analysis aims at identifying interesting product customizations to be ported to the core-asset base. However, existing tools do not fulfill engineers needs to conduct this practice. To address this issue, this Thesis elaborates on the SPL engineers' needs when conducting customization analysis, and proposes a data-warehouse approach to help SPL engineers on the analysis. Once the interesting customizations have been identified, the pruning needs to be enacted. This means that product code needs to be ported to the core-asset realm, while products are upgraded with newer functionalities and bug-fixes available in newer core-asset releases. Herein, synchronizing both parties through sync paths is required. However, the state of-the-art tools are not tailored to SPL sync paths, and this hinders synchronizing core-assets and products. To address this issue, this Thesis proposes to leverage existing Version Control Systems (i.e. git/Github) to provide sync operations as first-class construct

    Advanced Calibration of Automotive Augmented Reality Head-Up Displays = Erweiterte Kalibrierung von Automotiven Augmented Reality-Head-Up-Displays

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    In dieser Arbeit werden fortschrittliche Kalibrierungsmethoden für Augmented-Reality-Head-up-Displays (AR-HUDs) in Kraftfahrzeugen vorgestellt, die auf parametrischen perspektivischen Projektionen und nichtparametrischen Verzerrungsmodellen basieren. Die AR-HUD-Kalibrierung ist wichtig, um virtuelle Objekte in relevanten Anwendungen wie z.B. Navigationssystemen oder Parkvorgängen korrekt zu platzieren. Obwohl es im Stand der Technik einige nützliche Ansätze für dieses Problem gibt, verfolgt diese Dissertation das Ziel, fortschrittlichere und dennoch weniger komplizierte Ansätze zu entwickeln. Als Voraussetzung für die Kalibrierung haben wir mehrere relevante Koordinatensysteme definiert, darunter die dreidimensionale (3D) Welt, den Ansichtspunkt-Raum, den HUD-Sichtfeld-Raum (HUD-FOV) und den zweidimensionalen (2D) virtuellen Bildraum. Wir beschreiben die Projektion der Bilder von einem AR-HUD-Projektor in Richtung der Augen des Fahrers als ein ansichtsabhängiges Lochkameramodell, das aus intrinsischen und extrinsischen Matrizen besteht. Unter dieser Annahme schätzen wir zunächst die intrinsische Matrix unter Verwendung der Grenzen des HUD-Sichtbereichs. Als nächstes kalibrieren wir die extrinsischen Matrizen an verschiedenen Blickpunkten innerhalb einer ausgewählten "Eyebox" unter Berücksichtigung der sich ändernden Augenpositionen des Fahrers. Die 3D-Positionen dieser Blickpunkte werden von einer Fahrerkamera verfolgt. Für jeden einzelnen Blickpunkt erhalten wir eine Gruppe von 2D-3D-Korrespondenzen zwischen einer Menge Punkten im virtuellen Bildraum und ihren übereinstimmenden Kontrollpunkten vor der Windschutzscheibe. Sobald diese Korrespondenzen verfügbar sind, berechnen wir die extrinsische Matrix am entsprechenden Betrachtungspunkt. Durch Vergleichen der neu projizierten und realen Pixelpositionen dieser virtuellen Punkte erhalten wir eine 2D-Verteilung von Bias-Vektoren, mit denen wir Warping-Karten rekonstruieren, welche die Informationen über die Bildverzerrung enthalten. Für die Vollständigkeit wiederholen wir die obigen extrinsischen Kalibrierungsverfahren an allen ausgewählten Betrachtungspunkten. Mit den kalibrierten extrinsischen Parametern stellen wir die Betrachtungspunkte wieder her im Weltkoordinatensystem. Da wir diese Punkte gleichzeitig im Raum der Fahrerkamera verfolgen, kalibrieren wir weiter die Transformation von der Fahrerkamera in den Weltraum unter Verwendung dieser 3D-3D-Korrespondenzen. Um mit nicht teilnehmenden Betrachtungspunkten innerhalb der Eyebox umzugehen, erhalten wir ihre extrinsischen Parameter und Warping-Karten durch nichtparametrische Interpolationen. Unsere Kombination aus parametrischen und nichtparametrischen Modellen übertrifft den Stand der Technik hinsichtlich der Zielkomplexität sowie Zeiteffizienz, während wir eine vergleichbare Kalibrierungsgenauigkeit beibehalten. Bei allen unseren Kalibrierungsschemen liegen die Projektionsfehler in der Auswertungsphase bei einer Entfernung von 7,5 Metern innerhalb weniger Millimeter, was einer Winkelgenauigkeit von ca. 2 Bogenminuten entspricht, was nahe am Auflösungvermögen des Auges liegt
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