Time filter

Source Type

Karthaus D.,L Laboratory Research institute for automotive lighting and mechatronic | Sandfuchs O.,Hamm-Lippstadt University of Applied Sciences | Sinzinger S.,TU Ilmenau
Optics InfoBase Conference Papers | Year: 2016

To prepare holograms for application in automotive headlamps, LED characteristics are considered during design and simulation. First experimental results to verify algorithms are presented and necessary steps for further improvements are discussed. © OSA 2016.


Zadegan F.G.,Lund University | Krenz-Baath R.,Hamm-Lippstadt University of Applied Sciences | Larsson E.,Lund University
Proceedings - International Test Conference | Year: 2017

IEEE 1687 enables flexible access to on-chip instruments via dynamically reconfigurable networks. Reconfiguration allows reducing instrument access time by keeping only those instruments on the scan-path which are required for each access. To perform reconfiguration and execute commands described in instrument access procedures, scan vectors are generated in a process called retargeting. These vectors are then applied through a number of capture-shift-update (CSU) operations. Generating the optimal set of vectors w.r.t. application time is modeled as an Integer Linear Optimization Problem, which is an NP-hard problem. In the modeling, an IEEE 1687 network is represented as a sequential problem unrolled over a number of time frames, each frame corresponding to a CSU operation. A key challenge is to find the number of required CSU operations, which should be sufficiently high so that the optimal solution is included in the search space but kept as low as possible to keep the model less complex and thus suitable for large IEEE 1687 networks. In this work, we propose a method to compute an upper-bound on the number of required CSU operations. Through experiments, we show that our method results in a tight upper-bound, is applicable to a large variety of IEEE 1687 network designs, and is able to handle large designs. © 2016 IEEE.


Krakowski-Roosen H.,Hamm-Lippstadt University of Applied Sciences
Onkologe | Year: 2017

Background: In the press there are statements, such as “sport more important than a cancer medicine” and tumor patients regularly participate in a growing number of sports. What is the therapeutic value of sport for patients, what is the impact of such a sport offer and how often and intensively should sport be practiced? Questions that are asked by doctors, therapists and patients. Objectives: The potential of sport in the prevention of cancer should be considered in the sense of the three classical prevention levels (primary, secondary and tertiary): can practicing sport change the risk of developing cancer? Can sport contribute to the early detection of cancer? Does sport help tumor patients with their disease? Material and methods: This article is based on a selective literature search of the PubMed database for the topics “sports, exercise and physical activity” and “cancer”. In addition, data from the own patient population were evaluated. Results and conclusion: Epidemiological studies show an effective reduction of molecular factors, such as high insulin and insulin-like growth factor (IGF) levels as well as high insulin resistance through sport, which are high risk factors for numerous tumor diseases. Other factors, such as interleukin 6 (IL-6) are also mediators of the disease but are part of physiological adaptation responses to training in sport so that their role in the sense of a preventive causal chain can be critically questioned. The practice of sport and also negative side effects, such as increased intake of performance enhancing substances may also increase the risk of cancer. In the sense of secondary prevention, sports and sports scientific methods can contribute to uncovering threatening side effects of the disease, such as cachexia in the early stages of cancer. Concrete recommendations are given for the design of training programs for tumor patients. © 2017 Springer Medizin Verlag GmbH


Spura C.,Hamm-Lippstadt University of Applied Sciences
Forschung im Ingenieurwesen/Engineering Research | Year: 2015

Gear couplings are essential machine elements and where used in many areas of the gear and transmission technology. The significant advantages of gear couplings are the transmission of high drive power and torque in a small space, and the compensation of an existing radial and/or angular displacement. For this compensation a geometrically complicated special gearing and the knowledge of the load distribution within the teeth is essential. To calculate the load distribution, the focal factor is the tooth stiffness and its dependence on various influencing variables. The following article shows the basic principles and the present knowledge of the tooth stiffness calculation for gear couplings and shows the application of the methods for calculating the contemporary practical use in the design phase of this machine element. © 2015, Springer-Verlag Berlin Heidelberg.


Meyer J.,Hamm-Lippstadt University of Applied Sciences | Tappe F.,Hamm-Lippstadt University of Applied Sciences
Advanced Optical Materials | Year: 2015

The efficient generation of white light by phosphor-converted LEDs (pcLEDs) suffers from a trade-off between high color rendition, low correlated color temperatures, and luminous efficacy. While this is partially an inherent problem, it is also caused by the spectral efficiency of the materials used. The particular challenges for materials research lie, amongst the demanding general requirements, in finding very narrow-band or line-emitting materials: excitable with blue light, emitting in the near red. A way to design Mn(IV) activated line emitters is proposed, and methods for high-throughput combinatorial syntheses are specified. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Thomae D.,Jena University of Applied Sciences | Maass J.,Carl Zeiss GmbH | Sandfuchs O.,Hamm-Lippstadt University of Applied Sciences | Gatto A.,Carl Zeiss GmbH | Brunner R.,Jena University of Applied Sciences
Applied Optics | Year: 2014

A flexible illumination system for Talbot lithography is presented, in which the Talbot mask is illuminated by discrete but variable incidence angles. Changing the illumination angle stepwise in combination with different exposure doses for different angles offers the possibility to generate periodic continuous surface relief structures. To demonstrate the capability of this approach, two exemplary micro-optical structures were manufactured. The first example isa blazed grating with a stepsize of 1.5 μm. The second element is a specific beam splitter with parabolic-shaped grating grooves. The quality of the manufacturing process is evaluated on the basis of the optical performance of the resulting micro-optical elements. © 2014 Optical Society of America.


Sturm C.,Hamm-Lippstadt University of Applied Sciences | Strube G.,Albert Ludwigs University of Freiburg | Gouda S.,German University in Cairo
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2013

The consideration of cognitive differences between user groups in the field of human-computer interaction is still in its infancy. The present paper presents two explorative studies looking at the impact of the users' native language on their performance with different menu structures for mobile phones. Object- and verb-oriented menus with different levels of hierarchy were tested with users in Mexico and Germany. A follow-up study looked at the performance with verb- and object oriented menus by Arabic native speakers in Egypt. The results suggest that flat hierarchies are to be preferred independent from any cultural impact. While the first study did not yield a significant difference between Spanish and German native speakers using verb- and object-oriented menus, Arabic users performed significantly better with verb-oriented menus. © 2013 Springer-Verlag Berlin Heidelberg.


Bittmann B.,Schrodinger | Haupert F.,Hamm-Lippstadt University of Applied Sciences | Schlarb A.K.,University of Kaiserslautern
Journal of Applied Polymer Science | Year: 2012

Nanocomposites gained more and more importance in the last few years because of their improved performance over the neat polymer matrix, that is, toughness and stiffness can be enhanced simultaneously by the addition of nanoparticles. However, the dispersion of these particles in the matrix remains a big challenge. In this study, two types of TiO 2 nanoparticles were dispersed in two different epoxy resins by means of ultrasound. The particle size development in dependence on the dispersion time was investigated by dynamic light scattering for the different material systems. Furthermore, the influence of the viscosity on the sonication process' efficiency was analyzed. The resulting nanocomposites were tested for fracture and Charpy toughness. SEM images revealed that the improved fracture toughness properties are correlated to a rougher fracture surface, whose formation dissipates more energy. © 2011 Wiley Periodicals, Inc.


Shoukry L.,German University in Cairo | Sturm C.,Hamm-Lippstadt University of Applied Sciences | Galal-Edeen G.H.,American University in Cairo
2012 International Conference on E-Learning and E-Technologies in Education, ICEEE 2012 | Year: 2012

This paper discusses the causes, extent and implications of the digital language divide in technologies used by young Arabic-speaking children by the example of Egyptian preschoolers. The discussion is based on two studies: A preliminary survey examining the nature of Egyptian preschoolers' use of technology and an analytical evaluation of representative Arabic literacy developing applications available for Egyptian children compared to their English counterparts. © 2012 IEEE.


Grant
Agency: European Commission | Branch: FP7 | Program: CP | Phase: ICT-2013.3.1 | Award Amount: 4.65M | Year: 2014

Today, an average family spends annually over 50 Euros on No-Failure-Found (NFF) investigations - a known problem of an unknown origin. Tomorrow, the electronic engine control system in a car will be dying after two-three years of operation due to CMOS ageing. Actions are urgently needed!A group of European experts will unite their forces in BASTION to fight against ageing and NFF issues. The project will investigate currently unknown defects, uncertain fault coverage and unclassified field returns. A new defect universe will be assembled and faults will be classified into comprehensive classes. BASTION will study the mechanisms of ageing and improve the longevity of electronic products. Embedded instrumentation and the IEEE P1687 standard will be applied to develop an ultra-low-latency, scalable error detection and localization infrastructure as well as to integrate all heterogeneous technologies into a homogeneous system.The project will complete in three years, at only a negligible fraction of costs wasted by society on NFF annually.

Loading Hamm-Lippstadt University of Applied Sciences collaborators
Loading Hamm-Lippstadt University of Applied Sciences collaborators