Software- und Systemarchitekturevaluation und -Analysis in der Automotive Domäne

The complexity of software-intensive embedded systems in the automotive domain has been steadily growing in the recent years. As a consequence, controller-oriented development processes will be replaced by function-oriented ones. The main intention of function-oriented development is an initial decoupling of hardware and software. This increases the flexibility during development. Even more, the reuse of hardware and software components is supported. To handle these capabilities, a superior view on the structure of a system and its development rationale becomes necessary which is called the architecture of the system. Architecture evaluation has to be performed to assess the suitability of an architecture with respect to extra-functional requirements on the system, i.e.\ quality attributes. Thus, the development rationale can be expressed according to the quality attributes. In this work, an evaluation structure is proposed which is called the Quality Attribute Directed Acyclic Graph. It provides an explicit representation of extra-functional requirements and will be the basis not only for evaluation but also for architecture analysis. An evaluation methodology in terms of evaluation tactics for time-saving and cost-efficient evaluation processing is defined. Thus, an often great number of possible architecture variants can be handled without causing too much evaluation and thus development effort. Architecture analysis will be performed to understand evaluation results and to reason on development rationales. Analysis results are a valuable feedback for current as well as for future development projects. Architectural decisions on the system composition can be supported as their impact on the evaluation result can be predicted. Furthermore, promising architectural changes of architecture variants can be identified which again saves development effort. With growing and moreover expressible architectural knowledge, decisions can be supported more efficiently and even guided architecture development becomes conceivable. Besides documentation and communication, the whole development process profits from decision support as even quickly made decisions become more reliable.Die Komplexität Software-intensiver eingebetteter Systeme im Automobil ist in den letzten Jahrzehnten ständig gestiegen. Daher werden Steuergeräte-orientierte Prozesse durch Funktionen-orientierte ersetzt. Die Motivation Funktionen-orientierter Entwicklung liegt in der Entkopplung von Hardware und Software, um die Flexibilität in der Entwicklung zu erhöhen und die Wiederverwendung von Hardware und Software zu unterstützen. Um diese Möglichkeiten handhaben zu können, bedarf es einer übergeordneten Sicht auf das System und die angewendeten Prinzipien in der Entwicklung. Diese Sicht wird als Architektur des Systems bezeichnet. Durch Architekturevaluation wird die Eignung einer Architektur bezüglich extra-funktionaler Anforderungen an das System, so genannter Qualitätsattribute, festgestellt. Die angewendeten Entwicklungsprinzipien können vor dem Hintergrund der Qualitätsattribute aufgezeigt werden. In dieser Arbeit wird eine Evaluationsstruktur, der Quality Attribute Directed Acyclic Graph, vorgeschlagen. Sie bietet eine explizite Darstellung der extra-funktionalen Anforderungen und ist nicht nur die Grundlage für die Evaluation, sondern auch für Architekturanalyse. Eine Evaluationsmethodik wird in Form von Taktiken definiert, die eine zeitsparende und kosteneffiziente Durchführung der Evaluation versprechen. Daher kann eine oftmals sehr große Anzahl möglicher Architekturvarianten berücksichtigt werden, ohne dass zu großer Evaluations- und somit Entwicklungsaufwand entsteht. Architekturanalyse wird eingesetzt, um Evaluationsergebnisse besser zu verstehen und angewendete Entwicklungsprinzipien zu diskutieren. Die Ergebnisse der Architekturanalyse stellen eine wertvolle Rückmeldung in Bezug auf die erreichte Qualität sowohl in aktuellen als auch zukünftigen Projekten dar. Architekturentscheidungen bezüglich der Systemkomposition werden unterstützt, da der entsprechende Einfluss auf die Evaluationsergebnisse im Vorfeld abgeschätzt werden kann. Des Weiteren können vielversprechende Veränderungen von Architekturvarianten identifiziert werden, was abermals Entwicklungsaufwand spart. Mit steigendem und vor allem auch formulierbarem Architekturwissen können Architekturentscheidungen immer effizienter unterstützt werden. Sogar Architekturentwicklung mit entsprechender Werkzeug-basierter Unterstützung rückt in greifbare Nähe. Neben Dokumentation und Kommunikation profitiert der gesamte Entwicklungsprozess von einer Entscheidungsunterstützung, die schnelle und zuverlässige Entscheidungen ermöglicht

Dampak Pandemi Covid-19 terhadap Tenaga Kerja Formal di Indonesia

Even though the informal labour still dominates Indonesia workforce, the trend of formal labour increases each year. BPS data shows that in 2015, the percentage of formal labor reached 42,25 percent. Then it increased to 44,28 percent in 2019. As a capital-intensive sector, formal sector supports economy of Indonesia, because it is relatively safe or less prone to shut down. However, the determination of the global pandemic status on March 11, 2020 due to Corona Virus Disease (Covid-19) has hit the world economy, including Indonesia. To suppress the spread of Covid-19, people are asked to work, study, or pray from home. This causes many companies suffer losses and even close their businesses, thus impacting workers. Based on data from the Ministry of Manpower 13 April 2020 as many as 1.2 million formal labour have been furloughed and 212.4 thousand have been laid off. This study aims to observe the trends of formal labour in Indonesia and the impact of Covid-19 on formal labour in Indonesia. This study uses secondary data obtained from various sources which are analyzed descriptively

The RNA sequence context defines the mechanistic routes by which yeast arginyl-tRNA synthetase charges tRNA.

Arginylation of tRNA transcripts by yeast arginyl-tRNA synthetase can be triggered by two alternate recognition sets in anticodon loops: C35 and U36 or G36 in tRNA(Arg) and C36 and G37 in tRNA(Asp) (Sissler M, Giegé R, Florentz C, 1996, EMBO J 15:5069-5076). Kinetic studies on tRNA variants were done to explore the mechanisms by which these sets are expressed. Although the synthetase interacts in a similar manner with tRNA(Arg) and tRNA(Asp), the details of the interaction patterns are idiosyncratic, especially in anticodon loops (Sissler M, Eriani G, Martin F, Giegé R, Florentz C, 1997, Nucleic Acids Res 25:4899-4906). Exchange of individual recognition elements between arginine and aspartate tRNA frameworks strongly blocks arginylation of the mutated tRNAs, whereas full exchange of the recognition sets leads to efficient arginine acceptance of the transplanted tRNAs. Unpredictably, the similar catalytic efficiencies of native and transplanted tRNAs originate from different k(cat) and Km combinations. A closer analysis reveals that efficient arginylation results from strong anticooperative effects between individual recognition elements. Nonrecognition nucleotides as well as the tRNA architecture are additional factors that tune efficiency. Altogether, arginyl-tRNA synthetase is able to utilize different context-dependent mechanistic routes to be activated. This confers biological advantages to the arginine aminoacylation system and sheds light on its evolutionary relationship with the aspartate system.comparative studyjournal articleresearch support, non-u.s. gov't1998 Junimporte

Pathology-related mutation A7526G (A9G) helps in the understanding of the 3D structural core of human mitochondrial tRNA(Asp).

More than 130 mutations in human mitochondrial tRNA (mt-tRNA) genes have been correlated with a variety of neurodegenerative and neuromuscular disorders. Their molecular impacts are of mosaic type, affecting various stages of tRNA biogenesis, structure, and/or functions in mt-translation. Knowledge of mammalian mt-tRNA structures per se remains scarce however. Primary and secondary structures deviate from classical tRNAs, while rules for three-dimensional (3D) folding are almost unknown. Here, we take advantage of a myopathy-related mutation A7526G (A9G) in mt-tRNA(Asp) to investigate both the primary molecular impact underlying the pathology and the role of nucleotide 9 in the network of 3D tertiary interactions. Experimental evidence is presented for existence of a 9-12-23 triple in human mt-tRNA(Asp) with a strongly conserved interaction scheme in mammalian mt-tRNAs. Mutation A7526G disrupts the triple interaction and in turn reduces aspartylation efficiency.letterresearch support, non-u.s. gov't2009 Aug2009 06 17importe

Sequences outside recognition sets are not neutral for tRNA aminoacylation. Evidence for nonpermissive combinations of nucleotides in the acceptor stem of yeast tRNAPhe.

Phenylalanine identity of yeast tRNAPhe is governed by five nucleotides including residues A73, G20, and the three anticodon nucleotides (Sampson et al., 1989, Science 243, 1363-1366). Analysis of in vitro transcripts derived from yeast tRNAPhe and Escherichia coli tRNAAla bearing these recognition elements shows that phenylalanyl-tRNA synthetase is sensitive to additional nucleotides within the acceptor stem. Insertion of G2-C71 has dramatic negative effects in both tRNA frameworks. These effects become compensated by a second-site mutation, the insertion of the wobble G3-U70 pair, which by itself has no effect on phenylalanylation. From a mechanistic point of view, the G2-C71/G3-U70 combination is not a "classical" recognition element since its antideterminant effect is compensated for by a second-site mutation. This enlarges our understanding of tRNA identity that appears not only to be the outcome of a combination of positive and negative signals forming the so-called recognition/identity set but that is also based on the presence of nonrandom combinations of sequences elsewhere in tRNA. These sequences, we name "permissive elements," are retained by evolution so that they do not hinder aminoacylation. Likely, no nucleotide within a tRNA is of random nature but has been selected so that a tRNA can fulfill all its functions efficiently.journal articleresearch support, non-u.s. gov't1998 May 08importe

Armless mitochondrial tRNAs in enoplea (nematoda).

The mitochondrial genome of metazoan animal typically encodes 22 tRNAs. Nematode mt-tRNAs normally lack the T-stem and instead feature a replacement loop. In the class Enoplea, putative mt-tRNAs that are even further reduced have been predicted to lack both the T- and the D-arm. Here we investigate these tRNA candidates in detail. Three lines of computational evidence support that they are indeed minimal functional mt-tRNAs: (1) the high level of conservation of both sequence and secondary structure, (2) the perfect preservation of the anticodons, and (3) the persistence of these sequence elements throughout several genome rearrangements that place them between different flanking genes

Synthetic polyamines stimulate in vitro transcription by T7 RNA polymerase.

The influence of nine synthetic polyamines on in vitro transcription with T7 RNA polymerase has been studied. The compounds used were linear or macrocyclic tetra- and hexaamine, varying in their size, shape and number of protonated groups. Their effect was tested on different types of templates, all presenting the T7 RNA promoter in a double-stranded form followed by sequences encoding short transcripts (25 to 35-mers) either on single- or double-stranded synthetic oligodeoxyribonucleotides. All polyamines used stimulate transcription of both types of templates at levels dependent on their size, shape, protonation degree, and concentration. For each compound, an optimal concentration could be defined; above this concentration, transcription inhibition occurred. Highest stimulation (up to 12-fold) was obtained by the largest cyclic compound called [38]N6C10.comparative studyjournal articleresearch support, non-u.s. gov't1994 Jul 25importe

Major identity determinants for enzymatic formation of ribothymidine and pseudouridine in the T psi-loop of yeast tRNAs.

Almost all transfer RNA molecules sequenced so far contain two universal modified nucleosides at positions 54 and 55, respectively: ribothymidine (T54) and pseudouridine (psi 55). To identify the tRNA elements recognized by tRNA:m5uridine-54 methyltransferase and tRNA:pseudouridine-55 synthase from the yeast Saccharomyces cerevisiae, a set of 43 yeast tRNA(Asp) mutants were used. Some variants contained point mutations, while the others included progressive reductions in size down to a tRNA minisubstrate consisting of the T psi-loop with only one G.C base-pair as stem (9-mer). All substrates (full-sized tRNA(Asp) and various minihelices) were produced in vitro by T7 transcription and tested using yeast extract (S100) as a source of enzymatic activities and S-adenosyl-L-methionine as a methyl donor. The results indicate that the minimal substrate for enzymatic formation of psi 55 is a stem/loop structure with only four G.C base-pairs in the stem, while a longer stem is required for efficient T54 formation. None of the conserved nucleotides (G53, C56, A58 and C61) and U54 for psi 55 or U55 for T54 formation can be replaced by any of the other three canonical nucleotides. Yeast tRNA:m5uridine-54 methyltransferase additionally requires the presence of a pyrimidine-60 in the loop. Interestingly, in a tRNA(Asp) variant in which the T psi-loop was permuted with the anticodon-loop, the new U32 and U33 residues derived from the T psi-loop were quantitatively converted to T32 and psi 33, respectively. Structural mapping of this variant with ethylnitrosourea confirmed that the intrinsic characteristic structure of the T psi-loop was conserved upon permutation and that the displaced anticodon-loop did not acquire a T psi-loop structure. These results demonstrate that a local conformation rather than the exact location of the U-U sequence within the tRNA architecture is the important identity determinant for recognition by yeast tRNA:m5uridine-54 methyltransferase and tRNA:pseudouridine-55 synthase.journal articleresearch support, non-u.s. gov't1997 Dec 12importe

Search for characteristic structural features of mammalian mitochondrial tRNAs.

A number of mitochondrial (mt) tRNAs have strong structural deviations from the classical tRNA cloverleaf secondary structure and from the conventional L-shaped tertiary structure. As a consequence, there is a general trend to consider all mitochondrial tRNAs as "bizarre" tRNAs. Here, a large sequence comparison of the 22 tRNA genes within 31 fully sequenced mammalian mt genomes has been performed to define the structural characteristics of this specific group of tRNAs. Vertical alignments define the degree of conservation/variability of primary sequences and secondary structures and search for potential tertiary interactions within each of the 22 families. Further horizontal alignments ascertain that, with the exception of serine-specific tRNAs, mammalian mt tRNAs do fold into cloverleaf structures with mostly classical features. However, deviations exist and concern large variations in size of the D- and T-loops. The predominant absence of the conserved nucleotides G18G19 and T54T55C56, respectively in these loops, suggests that classical tertiary interactions between both domains do not take place. Classification of the tRNA sequences according to their genomic origin (G-rich or G-poor DNA strand) highlight specific features such as richness/poorness in mismatches or G-T pairs in stems and extremely low G-content or C-content in the D- and T-loops. The resulting 22 "typical" mammalian mitochondrial sequences built up a phylogenetic basis for experimental structural and functional investigations. Moreover, they are expected to help in the evaluation of the possible impacts of those point mutations detected in human mitochondrial tRNA genes and correlated with pathologies.journal articleresearch support, non-u.s. gov't2000 Octimporte