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排序方式: 共有634条查询结果,搜索用时 15 毫秒
1.
Heiko Drachenfels 《Informatik-Spektrum》1997,20(5):286-293
Eingegangen am 13.11.1996, in überarbeiteter Form am 12.5.1997 相似文献
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3.
Jan H. Dring Julian Schrter Jerome Jüngling Saskia Biskup Kerstin A. Klotz Thomas Bast Tobias Dietel G. Christoph Korenke Sophie Christoph Heiko Brennenstuhl Guido Rubboli Rikke S. Mller Gaetan Lesca Yves Chaix Stefan Klker Georg F. Hoffmann Johannes R. Lemke Steffen Syrbe 《International journal of molecular sciences》2021,22(6)
Pathogenic variants in KCNA2, encoding for the voltage-gated potassium channel Kv1.2, have been identified as the cause for an evolving spectrum of neurological disorders. Affected individuals show early-onset developmental and epileptic encephalopathy, intellectual disability, and movement disorders resulting from cerebellar dysfunction. In addition, individuals with a milder course of epilepsy, complicated hereditary spastic paraplegia, and episodic ataxia have been reported. By analyzing phenotypic, functional, and genetic data from published reports and novel cases, we refine and further delineate phenotypic as well as functional subgroups of KCNA2-associated disorders. Carriers of variants, leading to complex and mixed channel dysfunction that are associated with a gain- and loss-of-potassium conductance, more often show early developmental abnormalities and an earlier onset of epilepsy compared to individuals with variants resulting in loss- or gain-of-function. We describe seven additional individuals harboring three known and the novel KCNA2 variants p.(Pro407Ala) and p.(Tyr417Cys). The location of variants reported here highlights the importance of the proline(405)–valine(406)–proline(407) (PVP) motif in transmembrane domain S6 as a mutational hotspot. A novel case of self-limited infantile seizures suggests a continuous clinical spectrum of KCNA2-related disorders. Our study provides further insights into the clinical spectrum, genotype–phenotype correlation, variability, and predicted functional impact of KCNA2 variants. 相似文献
4.
Heiko Koziolek Bastian Schlich Steffen Becker Michael Hauck 《Empirical Software Engineering》2013,18(4):746-790
During software system evolution, software architects intuitively trade off the different architecture alternatives for their extra-functional properties, such as performance, maintainability, reliability, security, and usability. Researchers have proposed numerous model-driven prediction methods based on queuing networks or Petri nets, which claim to be more cost-effective and less error-prone than current practice. Practitioners are reluctant to apply these methods because of the unknown prediction accuracy and work effort. We have applied a novel model-driven prediction method called Q-ImPrESS on a large-scale process control system from ABB consisting of several million lines of code. This paper reports on the achieved performance prediction accuracy and reliability prediction sensitivity analyses as well as the effort in person hours for achieving these results. 相似文献
5.
The current Web Services Agreement specification draft proposes a simple request-response protocol for agreement creation
only addressing bilateral offer exchanges. This paper proposes a framework augmenting this WS-Agreement to enable negotiations
according to a variety of bilateral and multilateral negotiation protocols. The framework design is based on a thorough analysis
of taxonomies for negotiations from the literature in order to allow for capturing a variety of different negotiation models
within a single, WS-Agreement compatible, framework. In order to provide for the intended flexibility, the proposed protocol
takes a two-stage approach: a meta-protocol is conducted among interested parties to agree on a common negotiation protocol
first before the real negotiation is carried out in the second step due to the protocol established in the first step. 相似文献
6.
Anne Martens Heiko Koziolek Lutz Prechelt Ralf Reussner 《Empirical Software Engineering》2011,16(5):587-622
Model-based performance evaluation methods for software architectures can help architects to assess design alternatives and save costs for late life-cycle performance fixes. A recent trend is component-based performance modelling, which aims at creating reusable performance models; a number of such methods have been proposed during the last decade. Their accuracy and the needed effort for modelling are heavily influenced by human factors, which are so far hardly understood empirically. Do component-based methods allow to make performance predictions with a comparable accuracy while saving effort in a reuse scenario? We examined three monolithic methods (SPE, umlPSI, Capacity Planning (CP)) and one component-based performance evaluation method (PCM) with regard to their accuracy and effort from the viewpoint of method users. We conducted a series of three experiments (with different levels of control) involving 47 computer science students. In the first experiment, we compared the applicability of the monolithic methods in order to choose one of them for comparison. In the second experiment, we compared the accuracy and effort of this monolithic and the component-based method for the model creation case. In the third, we studied the effort reduction from reusing component-based models. Data were collected based on the resulting artefacts, questionnaires and screen recording. They were analysed using hypothesis testing, linear models, and analysis of variance. For the monolithic methods, we found that using SPE and CP resulted in accurate predictions, while umlPSI produced over-estimates. Comparing the component-based method PCM with SPE, we found that creating reusable models using PCM takes more (but not drastically more) time than using SPE and that participants can create accurate models with both techniques. Finally, we found that reusing PCM models can save time, because effort to reuse can be explained by a model that is independent of the inner complexity of a component. The tasks performed in our experiments reflect only a subset of the actual activities when applying model-based performance evaluation methods in a software development process. Our results indicate that sufficient prediction accuracy can be achieved with both monolithic and component-based methods, and that the higher effort for component-based performance modelling will indeed pay off when the component models incorporate and hide a sufficient amount of complexity. 相似文献
7.
3D mapping is very challenging in the underwater domain, especially due to the lack of high resolution, low noise sensors.
A new spectral registration method is presented that can determine the spatial 6 DOF transformation between pairs of very
noisy 3D scans with only partial overlap. The approach is hence suited to cope with sonar as the predominant underwater sensor.
The spectral registration method is based on Phase Only Matched Filtering (POMF) on non-trivially resampled spectra of the
3D data. 相似文献
8.
Many firms are considering ‘bring-your-own-device’ (BYOD) programs, under which their employees are allowed to bring their own devices to work and use them for both private and business purposes. This study examines what factors determine an employee's intention to participate in a corporate BYOD program and how such programs affect employer attractiveness. We approach our study of acceptance of corporate BYOD programs from the perspective of technology acceptance research. For this purpose, we propose a modified and extended UTAUT model. The model was tested by surveying students in their final term (n = 444). We show that performance expectancies have the strongest positive effect on intention, while perceived threats negatively impact intention. Finally, behavioural intention was positively associated with employer attractiveness, which leads to clear indications for companies considering establishing corporate BYOD programs. BYOD seems to play an increasingly important role in attracting and retaining future talent. 相似文献
9.
Huth J Buchholz M Kraus JM Mølhave K Gradinaru C v Wichert G Gress TM Neumann H Kestler HA 《Computer methods and programs in biomedicine》2011,104(2):227-234
The direct observation of cells over time using time-lapse microscopy can provide deep insights into many important biological processes. Reliable analyses of motility, proliferation, invasive potential or mortality of cells are essential to many studies involving live cell imaging and can aid in biomarker discovery and diagnostic decisions. Given the vast amount of image- and time-series data produced by modern microscopes, automated analysis is a key feature to capitalize the potential of time-lapse imaging devices. To provide fast and reproducible analyses of multiple aspects of cell behaviour, we developed TimeLapseAnalyzer. Apart from general purpose image enhancements and segmentation procedures, this extensible, self-contained, modular cross-platform package provides dedicated modalities for fast and reliable analysis of multi-target cell tracking, scratch wound healing analysis, cell counting and tube formation analysis in high throughput screening of live-cell experiments. TimeLapseAnalyzer is freely available (MATLAB, Open Source) at http://www.informatik.uni-ulm.de/ni/mitarbeiter/HKestler/tla. 相似文献
10.
Yannis Ioannidis Diego Milano Hans-Jörg Schek Heiko Schuldt 《International Journal on Digital Libraries》2008,9(2):101-114
DelosDLMS is a novel digital library management system (DLMS) that has been developed as an integration effort within the
DELOS Network of Excellence, a European Commission initiative funded under its fifth and sixth framework programs. In this
paper, we describe DelosDLMS that takes into account the recommendations of several activities that were initiated by DELOS
including the DELOS vision for digital libraries (DLs). A key aspect of DelosDLMS is its novel generic infrastructure that
allows the generation of digital library systems out of a set of basic system services and DL services in a modular and extensible
way. DL services like feature extraction, visualization, intelligent browsing, media-type-specific indexing, support for multilinguality,
relevance feedback and many others can easily be incorporated or replaced. A further key aspect of DelosDLMS is its robustness
against failures and its scalability for large collections and many parallel user requests. We discuss the current status
of an effort to build DelosDLMS, a Digital Library Management System that integrates in various ways several components developed
by DELOS members and showcases a great variety of functionality that is outlined as part of the DELOS vision. 相似文献