SMTIBEA: a hybrid multi-objective optimization algorithm for configuring large constrained software product lines

Software and Systems Modeling - A key challenge to software product line engineering is to explore a huge space of various products and to find optimal or near-optimal solutions that satisfy all...     

Referenzprozessabläufe für Telekommunikationsunternehmen

The telecommunication market is experiencing substantial changes. New business models, innovative services, and technologies require reengineering, transformation, and process standardization. Enterprise Architecture Frameworks support the transformation by specifying methods, procedures, and reference models. With the Enhanced Telecom Operation Map (eTOM), the TM Forum offers an international de facto reference process framework, based on specific features and requirements of the telecommunication industry. However, this reference framework only offers a hierarchical collection of processes on different levels of abstraction; a control view in terms of a sequential ordering of tasks and hence a real process flow as well as an end-to-end view on the customer are missing. In this paper, we extend the eTOM reference model by reference process flows, in which we abstract and generalize the knowledge about processes in telecommunication companies. With reference process flows, we aim to assist companies in achieving a structured and transparent re-structuring and re-design of their processes. We demonstrate the applicability and usefulness of our reference process flows in two case studies, and evaluate them by means of criteria for reference model evaluation. Our reference process flows have been accepted as a standard by the TM Forum and published as part of eTOM version 9. We further elaborate on those components of our approach which can be applied outside the telecommunication industry.     

Failure of Emergency Batteries for Aircrafts due to Stress-Corrosion Cracking

Several electrical brass (CuZn37) connector bolts of aircraft batteries failed as a result of stress-corrosion cracking. The batteries are used for emergency supply of the avionics in case of power failure or for complete control in the case of engine failure. For activation, the thermal battery is heated by a pyrotechnic element and then supplies electrical power with 5 A for 20 min up to 240 A for 3 min. For assembly of the batteries, an acetic acid curing silicone resin is used for housing seal on the lid and on the connector bolts. Because of the almost hermetic sealing of the enclosure, the silicone resin cures very slowly and metallic parts are exposed to the acetic acid vapor. So the electrical brass connector showed corrosive attack with the formation of copper acetate (verdigris). Subsequent failure due to stress-corrosion cracking occurred. The failure type and damage mechanisms could be simulated in laboratory experiments.     

Design patterns for behavior-based robotics

The use of patterns allows proven design expertise to be captured, communicated and reused in areas such as architecture and object-oriented programming. The artificial intelligence discipline of behavior-based robotics is an area in which such design expertise has undoubtedly accumulated, although it has not been captured and formalized. Consequently, the creation of these robotic systems remains a relatively unstructured process requiring a large amount of trial-and-error development. There is therefore a strong case for representing the previous design expertise which has been developed in this field. This paper describes how this may be achieved through the use of design patterns     

Evaluation of ethanol fermentation parameters for bioethanol production from sugar beet pulp and juice

The aim of this study was to investigate the efficient utilization of sugar beet pulp, as well as raw, concentrated raw and thick sugar beet juice, for bioethanol production. Different fermentation conditions were examined. The influence of raw material pre‐treatment (pasteurization or sterilization), type of batch culture process (stationary or shaken) as well as the type of Saccharomyces cerevisiae yeast preparation on the yields of the process were studied. Moreover, the fermentation process effectiveness was examined in connection with the quality of the obtained distillates. Sterilization, stationary batch culture and Safdistil C‐70 yeast preparation were identified as the most profitable factors for sugar beet pulp fermentation, providing a high fermentation efficiency and ethanol yield (87.7% of theoretical ethanol yield). Concentrated raw beet juice resulted in a value of 94.2% of theoretical yield, and thick juice a 92.6% yield. The results suggest that bioethanol production from sugar beet pulp and sugar beet juice has promise as an alternative fuel. The raw spirits obtained from the sugar beet juice were characterized as having the lowest quantity of volatile by‐products. Copyright © 2014 The Institute of Brewing & Distilling     

EMULSIFICATION OF OIL SAND BITUMEN IN CAUSTIC SOLUTION

Bitumen in the form of concentrated bitumen-in-water emulsion can be transported using a pipeline. Froth, which is a product of water based extraction of bitumen from oil sands, can be emulsified using NaOH. The emulsion can then be inverted by lowering pH to recover the bitumen. NaOH concentration, salt concentration, temperature, and mechanical energy input affect the formation of the emulsion and its viscosity. Optimum conditions for emulsion formation and inversion were specified.