Refine
Year of publication
Document Type
- Article (217) (remove)
Language
- English (217) (remove)
Keywords
- (Strict) sign-regularity (1)
- 1D-CNN (1)
- 3D urban planning (1)
- AAL (2)
- Aboriginal people (1)
- Abstract interpretation (1)
- Accelerometer calibration (1)
- Accelerometer sensor (1)
- Accelerometers (1)
- Actuators (1)
Institute
- Fakultät Architektur und Gestaltung (1)
- Fakultät Bauingenieurwesen (11)
- Fakultät Elektrotechnik und Informationstechnik (1)
- Fakultät Informatik (7)
- Fakultät Maschinenbau (3)
- Fakultät Wirtschafts-, Kultur- und Rechtswissenschaften (27)
- Institut für Angewandte Forschung - IAF (30)
- Institut für Optische Systeme - IOS (8)
- Institut für Strategische Innovation und Technologiemanagement - IST (6)
- Institut für Systemdynamik - ISD (27)
This work proposes a lossless data compression algorithm for short data blocks. The proposed compression scheme combines a modified move-to-front algorithm with Huffman coding. This algorithm is applicable in storage systems where the data compression is performed on block level with short block sizes, in particular, in non-volatile memories. For block sizes in the range of 1(Formula presented.)kB, it provides a compression gain comparable to the Lempel–Ziv–Welch algorithm. Moreover, encoder and decoder architectures are proposed that have low memory requirements and provide fast data encoding and decoding.
This work presents a new concept to implement the elliptic curve point multiplication (PM). This computation is based on a new modular arithmetic over Gaussian integer fields. Gaussian integers are a subset of the complex numbers such that the real and imaginary parts are integers. Since Gaussian integer fields are isomorphic to prime fields, this arithmetic is suitable for many elliptic curves. Representing the key by a Gaussian integer expansion is beneficial to reduce the computational complexity and the memory requirements of secure hardware implementations, which are robust against attacks. Furthermore, an area-efficient coprocessor design is proposed with an arithmetic unit that enables Montgomery modular arithmetic over Gaussian integers. The proposed architecture and the new arithmetic provide high flexibility, i.e., binary and non-binary key expansions as well as protected and unprotected PM calculations are supported. The proposed coprocessor is a competitive solution for a compact ECC processor suitable for applications in small embedded systems.
A conceptual framework for indigenous ecotourism projects – a case study in Wayanad, Kerala, India
(2020)
This paper analyses indigenous ecotourism in the Indian district of Wayanad, Kerala, using a conceptual framework based on a PATA 2015 study on indigenous tourism that includes the criteria: human rights, participation, business and ecology. Detailed indicator sets for each criterion are applied to a case study of the Priyadarshini Tea Environs with a qualitative research approach addressing stakeholders from the public sector, non-governmental organisations, academia, tour operators and communities including Adivasi and non-Adivasi. In-depth interviews were supported by participant and non-participant observations. The authors adapted this framework to the needs of the case study and consider that this modified version is a useful tool for academics and practitioners wishing to evaluate and develop indigenous ecotourism projects. The results show that the Adivasi involved in the Priyadarshini Tea Environs project benefit from indigenous ecotourism. But they could profit more if they had more involvement in and control of the whole tourism value chain.
Large-scale quantum computers threaten the security of today's public-key cryptography. The McEliece cryptosystem is one of the most promising candidates for post-quantum cryptography. However, the McEliece system has the drawback of large key sizes for the public key. Similar to other public-key cryptosystems, the McEliece system has a comparably high computational complexity. Embedded devices often lack the required computational resources to compute those systems with sufficiently low latency. Hence, those systems require hardware acceleration. Lately, a generalized concatenated code construction was proposed together with a restrictive channel model, which allows for much smaller public keys for comparable security levels. In this work, we propose a hardware decoder suitable for a McEliece system based on these generalized concatenated codes. The results show that those systems are suitable for resource-constrained embedded devices.
A flight-like absolute optical frequency reference based on iodine for laser systems at 1064 nm
(2017)
We present an absolute optical frequency reference based on precision spectroscopy of hyperfine transitions in molecular iodine 127I2 for laser systems operating at 1064 nm. A quasi-monolithic spectroscopy setup was developed, integrated, and tested with respect to potential deployment in space missions that require frequency stable laser systems. We report on environmental tests of the setup and its frequency stability and reproducibility before and after each test. Furthermore, we report on the first measurements of the frequency stability of the iodine reference with an unsaturated absorption cell which will greatly simplify its application in space missions. Our frequency reference fulfills the requirements on the frequency stability for planned space missions such as LISA or NGGM.
Introduction. Despite its high accuracy, polysomnography (PSG) has several drawbacks for diagnosing obstructive sleep apnea (OSA). Consequently, multiple portable monitors (PMs) have been proposed. Objective. This systematic review aims to investigate the current literature to analyze the sets of physiological parameters captured by a PM to select the minimum number of such physiological signals while maintaining accurate results in OSA detection. Methods. Inclusion and exclusion criteria for the selection of publications were established prior to the search. The evaluation of the publications was made based on one central question and several specific questions. Results. The abilities to detect hypopneas, sleep time, or awakenings were some of the features studied to investigate the full functionality of the PMs to select the most relevant set of physiological signals. Based on the physiological parameters collected (one to six), the PMs were classified into sets according to the level of evidence. The advantages and the disadvantages of each possible set of signals were explained by answering the research questions proposed in the methods. Conclusions. The minimum number of physiological signals detected by PMs for the detection of OSA depends mainly on the purpose and context of the sleep study. The set of three physiological signals showed the best results in the detection of OSA.
In several organizations, business workgroups autonomously implement information technology (IT) outside the purview of the IT department. Shadow IT, evolving as a type of workaround from nontransparent and unapproved end-user computing (EUC), is a term used to refer to this phenomenon, which challenges norms relative to IT controllability. This report describes shadow IT based on case studies of three companies and investigates its management. In 62% of cases, companies decided to reengineer detected instances or reallocate related subtasks to their IT department. Considerations of risks and transaction cost economics with regard to specificity, uncertainty, and scope explain these actions and the resulting coordination of IT responsibilities between the business workgroups and IT departments. This turns shadow IT into controlled business-managed IT activities and enhances EUC management. The results contribute to the governance of IT task responsibilities and provide a way to formalize the role of workarounds in business workgroups.
The McEliece cryptosystem is a promising candidate for post-quantum public-key encryption. In this work, we propose q-ary codes over Gaussian integers for the McEliece system and a new channel model. With this one Mannheim error channel, errors are limited to weight one. We investigate the channel capacity of this channel and discuss its relation to the McEliece system. The proposed codes are based on a simple product code construction and have a low complexity decoding algorithm. For the one Mannheim error channel, these codes achieve a higher error correction capability than maximum distance separable codes with bounded minimum distance decoding. This improves the work factor regarding decoding attacks based on information-set decoding.
A new thermal shock application-oriented testing method for ceramic components and refractories
(2019)
Ceramics and refractories are often used in high-temperature applications like industrial furnaces. Therefore, thermomechanical and heat resistance of ceramic and refractory materials are important. The material behaviour is described by thermal stress resistance. Established material tests to determine thermal shock behaviour are complex and do not yield key figures. The potential of application-related material testing in combination with simulations with transfer from ceramics to refractories is described below. The combination of model-based simulation with applied material testing offers numerous advantages. On the one hand, the design of the test setup is supported by the simulation, which results in a goal and application-oriented test setup. On the other hand, the iterative approach allows the model verification with the help of the applied material testing. The simulation shows that the transfer from ceramics to refractory material is possible and results according to literature. The design reliability of the components is thereby improved, since initially different loads can be simulated in the model in combination with a variety of materials and geometries, and thereby substitute complex and expensive preliminary tests. As a result, verified models offer a great savings potential in terms of time to market, development expenses and use of raw materials. Very important is, that the method is suitable for technical ceramics and refractory materials.
Background
This is a systematic review protocol to identify automated features, applied technologies, and algorithms in the electronic early warning/track and triage system (EW/TTS) developed to predict clinical deterioration (CD).
Methodology
This study will be conducted using PubMed, Scopus, and Web of Science databases to evaluate the features of EW/TTS in terms of their automated features, technologies, and algorithms. To this end, we will include any English articles reporting an EW/TTS without time limitation. Retrieved records will be independently screened by two authors and relevant data will be extracted from studies and abstracted for further analysis. The included articles will be evaluated independently using the JBI critical appraisal checklist by two researchers.
Discussion
This study is an effort to address the available automated features in the electronic version of the EW/TTS to shed light on the applied technologies, automated level of systems, and utilized algorithms in order to smooth the road toward the fully automated EW/TTS as one of the potential solutions of prevention CD and its adverse consequences.