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Search Results: 1 - 10 of 2164 matches for " Mike Lahl "
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Hot Rolling of Large Gears  [PDF]
Dirk Landgrebe, Andreas Sterzing, Mike Lahl, Thomas Druwe, Anne Manuela Taubert
Open Access Library Journal (OALib Journal) , 2017, DOI: 10.4236/oalib.1103152
Abstract:
Forming processes are generally characterized by a high degree of material utilization as well as short process times and, consequently, a decent economic efficiency. Furthermore, incremental forming enables the use of relatively low forming forces which results in a more compact design of the used machines. These conveniences are utilized in terms of roll forming with round tools to form gears and threads in a competitive way. Based on experiences gained over many years of researching rolling technologies, a cross-rolling process characterized by round tools with outer gearings was elaborated to realize a hot forming process of large gears at the Fraunhofer IWU. At actual project GEARFORM, a scaled sun gear demonstrator from wind gear application could be realized by hot rolling technology. An optimized rolling time was achieved by 32.5 seconds.
Risk based management of chemicals and products in a circular economy at a global scale (risk cycle), extended producer responsibility and EU legislation
Uwe Lahl, Barbara Zeschmar-Lahl
Environmental Sciences Europe , 2013, DOI: 10.1186/2190-4715-25-3
Abstract: The problem of cycling of pollutants within global waste recycling streams (risk cycle) can be solved in principle with the aid of REACH regulations. According to the demands of the REACH guidance documents, risk cycle associated emissions would have to be identified during the development of exposure scenarios and to be reduced by risk management measures. This would also apply to chemicals in electronic scrap as they pose health risks to workers at recycling sites with poor working conditions e.g. in Africa and Asia -- regardless if exported illegally. Therefore it is necessary to check whether the substance dossiers of these chemicals, that have or had to be submitted under REACH, have considered such exposure scenarios.Following the extended producer responsibility, there is a need for action. Within the context of European legislation, risk cycle of pollutants can be particularly addressed in the framework of the European chemicals legislation REACH. The legal options are given in principle. However, it is unclear whether the waste life cycle stage (risk cycle) has been and is included sufficiently within substance registration and regulatory review of the registration dossier. Integrating the effects of recycling in developing countries into the REACH regulation is undoubtedly a major challenge. But without doubt avoiding the cycling of pollutants within global waste recycling streams (risk cycle) is a major challenge, too, and in addition one of the core tasks of extended producer responsibility.
Monitoring the complexity of ventricular response in atrial fibrillation
H. K smacher,S. Wiese,M. Lahl
Discrete Dynamics in Nature and Society , 2000, DOI: 10.1155/s1026022600000066
Abstract: Atrial fibrillation does not present a uniform extent of variability of the ventricular response exemplifying periodicities and more complex fluctuations, due to varying number and shape of atrial wavelets and aberrant conduction in the AV-junction. It was sought to categorise different degrees of complexity introducing an uncomplicated monitoring method for that objective.
Efficacy of Facebook Fans: Can They Influence Perception of the Brand?  [PDF]
Mike Behan
Open Journal of Business and Management (OJBM) , 2014, DOI: 10.4236/ojbm.2014.24033
Abstract: Using a qualitative single case study methodology, this research studied the effect that a Facebook page has on friends of the brand. The problem under investigation is the lack of understanding effects social media sites like Facebook has on the perception of the brand by the user. The data collected suggests that the use of Facebook by a SME does help maintain and in some cases increase the perception of the brand in the positive. The analysis of the data additionally shows this effect on brand perception is based on the drivers of a) connectivity, b) change of perception, c) internal value, d) goodwill, and e) the decision process. Interview participants indicate the importance Facebook has as a marketing communication tool. The findings from the research suggest that Facebook use by SMEs is an important component of an integrated approach to marketing communications when considering the perception of the brand. This research also raises important questions as to what significance Facebook use by SMEs has over other traditional marketing communication methods when creating, communicating, and delivering a message of value.
Evaluation of the effects of adenotonsillar hypertrophy and adenotonsillectomy on growth in children
Levent Kartal,Mehmet ?lhan ?ahin,?smail Külahl,Mustafa Kendirci
Turk Pediatri Ar?ivi , 2012,
Abstract: Aim: Several factors including genetic factors, nutrition and environment play a critical role in the growth of children. Adenotonsillar hypertrophy (ATH) can cause growth retardation by obstructing the upper airway. Surgical treatment of ATH has been considered to have a positive effect on growth. The aim of this study was to evaluate the role of chronic ATH on growth by measuring weight, height, body mass index (BMI), bone age, serum insulin-like growth factor 1 (IGF-1) and insulin-like growth factor binding protein 3 (IGFBP-3) values before and after adenotonsillectomy.Material and Method: The study was approved by the Ethics Committee (4.5.2004; 04/170) and written informed consents were obtained from parents of the participants. A total of 40 prepubertal children who were diagnosed as chronic ATH were enrolled. Obstructive symptoms were questioned in the medical history before surgery. Weight, height, BMI and bone age values were measured and compared with reference values. Preoperative serum IGF-1 and IGFBP-3 values were compared with the control group which consisted of healthy children. Rates of obstructive symptoms, weight, height, BMI, bone age, serum IGF-1 and IGFBP-3 values of the patients were determined seven months after adenotonsillectomy and were compared with preoperative values. Results: Obstructive symptoms in children with ATH decreased remarkably after surgery. Preoperative mean value of bone age of the patients was statistically lower than reference values (p<0.05) and mean value of serum IGF-1 was lower than than the control group (p<0.05). IGF-1 and IGFBP-3 values did not increase significantly after surgery (p>0.05). However, growth retardation was detected in three out of 40 patients based on the anthropometric measurements.Conclusions: In this study, antropometric findings showed that chronic ATH did not cause significant growth retardation in prepubertal children. In addition, we could not prove that surgical treatment of ATH improved the growth in the postoperative follow-up period of seven months. This result may be related with our study population with a limited number of patients who had baseline growth retardation and short postoperative follow up period. Further studies with large number of patients and longer postoperative follow-up periods are required to determine the exact role of chronic ATH in growth retardation. (Turk Arch Ped 2012; 47: 260-6)
Functionalization of Polypropylene with High Dielectric Properties: Applications in Electric Energy Storage  [PDF]
T. C. Mike Chung
Green and Sustainable Chemistry (GSC) , 2012, DOI: 10.4236/gsc.2012.22006
Abstract: Biaxial-oriented polypropylene (BOPP) thin films are currently used as dielectrics in state-of-the-art capacitors that show many advantages, such as low energy loss and high breakdown strength, but a limited energy density (<2 J/cm3). This paper reviews some of our experimental results in functionalization of polypropylene with the objective to increase its electric energy density and maintain all desirable properties. A family of PP copolymers with various moieties, such as OH, O-Si(CH3)3, long chain branching, and cross-linking structure, have been systematically synthesized and studied to examine their dielectric properties (i.e. dielectric constant, dielectric loss, breakdown strength, polarization under various temperatures and electric fields). Evidently, a high molecular weight poly(propylene-co-hexen-6-ol) copolymer (PP-OH) containing 4.2 mol% of polar OH groups shows a dielectric constant (ε) of about 4.6 (more than 2 times of BOPP)—which is independent on a wide range of temperatures and frequencies—and high breakdown strength > 600 MV/m. The PP-OH dielectric demonstrates a linear reversible charge storage behavior with high releasing energy density > 7 J/cm3 (2 - 3 times of BOPP) after an applied electric field at E = 600 MV/m, without showing any significant increase of energy loss and remnant polarization at zero electric field. On the other hand, a cross-linked polypropylene (x-PP) exhibits an ε ~ 3, which is independent of a wide range of temperatures and frequencies, slim polarization loops, high breakdown strength (E = 650 MV/m), narrow breakdown distribution, and reliable energy storage capacity > 5 J/cm3 (double that of state-of-the-art BOPP capacitors), without showing any increase in energy loss.
Learning the Business  [PDF]
Mike Holcombe, Marian Gheorghe
Creative Education (CE) , 2012, DOI: 10.4236/ce.2012.32042
Abstract: Developing software is a highly creative process. This paper describes a novel approach to teaching software engineering which involves university students working in partnership with external clients from business, charities and the public sector building solutions to their business and other problems. The paper describes the basic principles behind these activities and focuses on the experiences of teaching advanced students through the medium of a commercial software development company specifically set up to be run by the students as part of their degree course. The evidence from student and employer feedback demonstrates that this approach has been highly successful for the past 20 years or so but despite this it has rarely, if ever, been replicated elsewhere.
Femoral Hernia: A Review of the Clinical Anatomy and Surgical Treatment  [PDF]
Makio Mike, Nobuyasu Kano
Surgical Science (SS) , 2013, DOI: 10.4236/ss.2013.410089
Abstract:

Purpose: Femoral hernia is a kind of ventral hernia that surgeons commonly encounter, second in frequency only to inguinal hernia. Femoral hernias often require emergency surgery because of incarceration or strangulation of the intestine. In addition, intestinal resection may need to be considered based on intestinal viability. Definitive preoperative diagnosis and strategic planning for surgery are thus important. The surgeon should consider the operation in the context of the clinical anatomy of the abdominal cavity. Therefore the essence of the clinical anatomy and treatment of femoral hernia is described. Methods: The medical records of 38 patients who underwent femoral hernia repair between March 2006 and November 2011 were retrospectively analyzed. Results: Femoral hernioplasty was performed with original mesh repair or Ruggi’s repair plus iliopubic tract repair (or Bassini’s repair). The mean patient age was 76.7 years, and a female predominance was apparent. Twenty-four patients underwent emergency surgery with a diagnosis of incarcerated femoral hernia. Nine patients showed intestinal strangulation and underwent resection of the small intestine. Four patients developed complications. One patient died due to aspiration pneumonia. No recurrences were encountered after 6 months to 6 years of follow-up. Conclusion: Femoral hernia is an important surgical condition with high rates of incarceration/strangulation and intestinal resection. Correct preoperative diagnosis of femoral hernia and a strict operative strategy are important. The original mesh repair is effective and easy to perform.

Managing Dynamics in Corporate Networks  [PDF]
Mike Danilovic, Mats Winroth
World Journal of Engineering and Technology (WJET) , 2014, DOI: 10.4236/wjet.2014.21004
Abstract: A crucial issue in collaborating in manufacturing corporate networks between different companies is to identify to what extent different strategic and operational decisions need to be coordinated between the involved companies. In this paper, we elaborate on the issue of synchronization and coordination of information flow based on interconnectivities between companies in order to coordinate a corporate network by the means of DSM, Dependence Structure Matrix. The results show that DSM can be used to identify interconnectivities, dependencies on information flow among actors in a network and to identify which information needs to be shared between companies in the network.
Sleep Loss Produces False Memories
Susanne Diekelmann, Hans-Peter Landolt, Olaf Lahl, Jan Born, Ullrich Wagner
PLOS ONE , 2008, DOI: 10.1371/journal.pone.0003512
Abstract: People sometimes claim with high confidence to remember events that in fact never happened, typically due to strong semantic associations with actually encoded events. Sleep is known to provide optimal neurobiological conditions for consolidation of memories for long-term storage, whereas sleep deprivation acutely impairs retrieval of stored memories. Here, focusing on the role of sleep-related memory processes, we tested whether false memories can be created (a) as enduring memory representations due to a consolidation-associated reorganization of new memory representations during post-learning sleep and/or (b) as an acute retrieval-related phenomenon induced by sleep deprivation at memory testing. According to the Deese, Roediger, McDermott (DRM) false memory paradigm, subjects learned lists of semantically associated words (e.g., “night”, “dark”, “coal”,…), lacking the strongest common associate or theme word (here: “black”). Subjects either slept or stayed awake immediately after learning, and they were either sleep deprived or not at recognition testing 9, 33, or 44 hours after learning. Sleep deprivation at retrieval, but not sleep following learning, critically enhanced false memories of theme words. This effect was abolished by caffeine administration prior to retrieval, indicating that adenosinergic mechanisms can contribute to the generation of false memories associated with sleep loss.
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