A Full-fledged Commit Message Quality Checker Based on Machine Learning

Commit messages (CMs) are an essential part of version control. By providing important context in regard to what has changed and why, they strongly support software maintenance and evolution. But writing good CMs is difficult and often neglected by developers. So far, there is no tool suitable for practice that automatically assesses how well a CM is written, including its meaning and context. Since this task is challenging, we ask the research question: how well can the CM quality, including semantics and context, be measured with machine learning methods? By considering all rules from the most popular CM quality guideline, creating datasets for those rules, and training and evaluating state-of-the-art machine learning models to check those rules, we can answer the research question with: sufficiently well for practice, with the lowest F$_1$ score of 82.9\%, for the most challenging task. We develop a full-fledged open-source framework that checks all these CM quality rules. It is useful for research, e.g., automatic CM generation, but most importantly for software practitioners to raise the quality of CMs and thus the maintainability and evolution speed of their software.Comment: published at COMPSAC'2

Feasibility study to use an SRAM-based FPGA in the readout electronics of the upgraded LHCb Outer Tracker detector

This thesis presents a study of the feasibility to use SRAM-based FPGAs as central component of the upgraded LHCb Outer Tracker readout electronics. The FPGA should contain the functionality of a TDC and should provide fast data links using multi-GBit/s transceivers. The TDC core that was developed provides 5 bit time measurements for 32 channels with a bin size of 780 ps. The TDC has the required time resolution of better than 1 ns. This was achieved by manually placing every logic element of the TDC channels and with an iterative procedure feeding timing measurements back to the Place&Route step of the router software. A transceiver and TDC card, and an adapter board for the existing readout electronics was developed. Both boards were used successfully to read out drift times from an Outer Tracker straw-tube module in a cosmic setup. To qualify the proposed electronics for the expected radiation levels an irradiation test with 22 MeV protons and two FPGA boards was performed up to a total ionization dose of 30 Mrad. Both chips sustained the irradiation expected for the full life time of the upgraded LHCb detector of up to 30 krad. After an irradiation dose of 150 krad the first deteriorations of the performance of the chips were observed. The proton cross section for configuration bit flips was determined to be 1.6*10^16cm^2 per bit. The measured error rate scaled to the upgrade environment would correspond to a manageable firmware error rate

Perceived Access to Health Care Services and Relevance of Telemedicine during the COVID-19 Pandemic in Germany

During the COVID-19 pandemic in Germany, non-pharmaceutical interventions were imposed to contain the spread of the virus. Based on cross-sectional waves in March, July and December 2020 of the COVID-19 Snapshot Monitoring (COSMO), the present study investigated the impact of the introduced measures on the perceived access to health care. Additionally, for the wave in December, treatment occasion as well as utilization and satisfaction regarding telemedicine were analysed. For 18–74-year-old participants requiring medical care, descriptive and logistic regression analyses were performed. During the less strict second lockdown in December, participants reported more frequently ensured access to health care (91.2%) compared to the first lockdown in March (86.8%), but less frequently compared to July (94.2%) during a period with only mild restrictions. In December, main treatment occasions of required medical appointments were check-up visits at the general practitioner (55.2%) and dentist (36.2%), followed by acute treatments at the general practitioner (25.6%) and dentist (19.0%), treatments at the physio-, ergo- or speech therapist (13.1%), psychotherapist (11.9%), and scheduled hospital admissions or surgeries (10.0%). Of the participants, 20.0% indicated utilization of telemedical (15.4% telephone, 7.6% video) consultations. Of them, 43.7% were satisfied with the service. In conclusion, for the majority of participants, access to medical care was ensured during the COVID-19 pandemic; however, access slightly decreased during phases of lockdown. Telemedicine complemented the access to medical appointments.Peer Reviewe

Die Wohnungs- und Immobilienwirtschaft als Impulsgeber und Unterstützer für moderne Wohn- und Lebensformen im Alter

DIE WOHNUNGS- UND IMMOBILIENWIRTSCHAFT ALS IMPULSGEBER UND UNTERSTÜTZER FÜR MODERNE WOHN- UND LEBENSFORMEN IM ALTER Die Wohnungs- und Immobilienwirtschaft als Impulsgeber und Unterstützer für moderne Wohn- und Lebensformen im Alter / Färber, Michael (Rights reserved) ( -

Wen erreicht Wissenschaftskommunikation nicht?

Das Karlsruher Institut für Technologie, Department Wissenschaftskommunikation, hat zusammen mit Wissenschaft im Dialog und gefördert von der Robert Bosch Stiftung von 2017 bis 2020 im Projekt „Wissenschaft für alle“ systematisch untersucht, welche Bevölkerungsgruppen bisher nicht oder kaum von Wissenschaftskommunikation erreicht werden, warum sie nicht erreicht werden und wie man das ändern kann. Die im Rahmen eines Literaturreviews bestätigte Heterogenität und die Vielfalt der bisher nicht erreichten Gruppen macht es schwierig, diese klar zu definieren. Meist führen ein Zusammenspiel verschiedener Exklusionsfaktoren (-> Intersektionalität) bzw. ursächlich deren fehlende oder unzureichende Berücksichtigung seitens der Wissenschaftskommunikation zu einer Ausgrenzung. Daher wurde zur Systematisierung der Rechercheergebnisse in der vorliegenden Typologie der Fokus anstatt auf gesellschaftliche Gruppen auf diese Faktoren gelegt. Die Zuordnung der Faktoren zu drei Ebenen soll einen systematisierten Überblick geben, ist aber keinesfalls als Zuschreibung eines Defizits oder einer Schuld zu sehen. Die Verantwortung für die Gestaltung inklusiver Angebote liegt in allen Fällen bei den Wissenschaftsorganisationen. Dieses Wimmelbild richtet sich an Akteur*innen in der Wissenschaft und Wissenschaftskommunikation und soll zum Nachvollziehen und Reflektieren aller im Projekt identifizierten 31 Exklusionsfaktoren (mit einem * markierte Faktoren sind übergreifende Konzepte mehrerer anderer Faktoren) anregen. Die Faktoren sind den in der aufgestellten Typologie formulierten drei Kategorien zugeschrieben, aber frei in der Grafik verteilt. Die Visualisierungen zeigen beispielhafte Diskriminierungserfahrungen, Diversity-Defizite und symbolische Darstellungen von strukturellen Problemen. Das Wimmelbild wird um Infografik-Elemente ergänzt, die ausgewählte statistische Informationen wiedergeben

Hybride Datenbankarchitekturen am Beispiel der neuen SAP In-Memory-Technologie

Die Verfügbarkeit neuer Technologien wie Multi-Core, SSD oder große Hauptspeicherkapazitäten bieten eine Gelegenheit, die klassischen Architekturansätze von Datenbanksystemen zu überdenken und an bestimmten Stellen zu korrigieren. In diesem Beitrag stellen wir die Grobstruktur der neuen hauptspeicherzentrierten SAP Technologie als einen Ansatz einer kommerziellen Umsetzung moderner Architekturkonzepte vor. Zentrales Design-Kriterium ist dabei ein hybrider Ansatz, um eine möglichst hohe Anzahl von Anforderungsvarianten optimal zu unterstützen. Nach einer Einleitung führt der Artikel durch die wichtigsten Architekturkomponenten und illustriert den grundsätzlichen Aufbau des Systems. Für einen „deep dive“ werden zwei Bereiche in Teil 3 und 4 des Artikels im Detail diskutiert. Dabei greift der Artikel zum einen den Aspekt der physischen Optimierung im Kontext eines hauptspeicherzentrierten Systems auf und diskutiert unterschiedliche Komprimierungs- und Sortierungskriterien, wie sie im klassischen disk-zentrierten Ansatz nicht zu finden sind. Zum anderen wird die Unterstützung von Planungsanwendungen skizziert, wodurch ein Einblick in die spezifische Unterstützung einer Anwendungsdomäne („business planning“) und die prinzipiellen Erweiterungen für komplexe Operationen zur direkten Unterstützung von darauf aufbauender Planungsfunktionalität gezeigt werden

d-d Dative Bonding Between Iron and the Alkaline-Earth Metals Calcium, Strontium, and Barium

Double deprotonation of the diamine 1,1 '-(tBuCH(2)NH)-ferrocene (1-H-2) by alkaline-earth (Ae) or Eu(II)metal reagents gave the complexes1-Ae (Ae=Mg, Ca, Sr, Ba) and1-Eu.1-Mg crystallized as a monomer while the heavier complexes crystallized as dimers. The Fe...Mg distance in1-Mg is too long for a bonding interaction, but short Fe...Ae distances in1-Ca,1-Sr, and1-Ba clearly support intramolecular Fe...Ae bonding. Further evidence for interactions is provided by a tilting of the Cp rings and the related(1)H NMR chemical-shift difference between the Cp alpha and beta protons. While electrochemical studies are complicated by complex decomposition, UV/Vis spectral features of the complexes support Fe -> Ae dative bonding. A comprehensive bonding analysis of all1-Ae complexes shows that the heavier species1-Ca,1-Sr, and1-Ba possess genuine Fe -> Ae bonds which involve vacant d-orbitals of the alkaline-earth atoms and partially filled d-orbitals on Fe. In1-Mg, a weak Fe -> Mg donation into vacant p-orbitals of the Mg atom is observed

Towards Scalable Real-time Analytics:: An Architecture for Scale-out of OLxP Workloads

We present an overview of our work on the SAP HANA Scale-out Extension, a novel distributed database architecture designed to support large scale analytics over real-time data. This platform permits high performance OLAP with massive scale-out capabilities, while concurrently allowing OLTP workloads. This dual capability enables analytics over real-time changing data and allows fine grained user-specified service level agreements (SLAs) on data freshness. We advocate the decoupling of core database components such as query processing, concurrency control, and persistence, a design choice made possible by advances in high-throughput low-latency networks and storage devices. We provide full ACID guarantees and build on a logical timestamp mechanism to provide MVCC-based snapshot isolation, while not requiring synchronous updates of replicas. Instead, we use asynchronous update propagation guaranteeing consistency with timestamp validation. We provide a view into the design and development of a large scale data management platform for real-time analytics, driven by the needs of modern enterprise customers

SAP HANA distributed in-memory database system: Transaction, session, and metadata management

One of the core principles of the SAP HANA database system is the comprehensive support of distributed query facility. Supporting scale-out scenarios was one of the major design principles of the system from the very beginning. Within this paper, we first give an overview of the overall functionality with respect to data allocation, metadata caching and query routing. We then dive into some level of detail for specific topics and explain features and methods not common in traditional disk-based database systems. In summary, the paper provides a comprehensive overview of distributed query processing in SAP HANA database to achieve scalability to handle large databases and heterogeneous types of workloads

The Hatfield-System versus the Weekly Undulating Periodised Resistance Training in trained males: Effects of a third mesocyle

We recently demonstrated that recreationally strength trained men, randomly assigned to either a Hatfield-System (HAT) group or a weekly undulating periodisation (WUP) group showed significant increases in strength and power during only 2 mesocycles (6 weeks) without differences between groups. The questions arise, whether an additional mesocycle would further enhance strength and power equally or differently between groups. The same 26 strength trained men, assigned to the HAT (n = 13; age = 26.8 ± 7.2 years) or to WUP (n = 13; age = 29.2 ± 9.0 years) performed an additional mesocycle (3 weeks). Anthropometric measures and strength testing were performed again after finishing the third mesocycle and were then compared with the results recorded after the second mesocycle. Both the HAT and WUP groups made significant (p ≤ 0.05) increases in strength and power – to approximately the same extent, again, without significant differences between groups. Thus, HAT and WUP are similarly effective over a nine-week training period, and the decision to use HAT or WUP depends on the preferences of the individual athlete