Fahrplanoptimierung für innerbetriebliche Routenverkehre

Innerbetriebliche Routenverkehre finden in der Praxis eine immer breitere Anwendung zur hochzyklischen Bereitstellung kleinerer Losgrößen. Die Auslegung solcher Systeme stellt jedoch aufgrund der zahlreichen Randbedingungen eine komplexe Aufgabe dar. In diesem Beitrag werden verbreitete Dimensionierungsmethoden für getaktete Routenverkehre beschrieben und darauf aufbauend ein Modell entwickelt, mit dessen Hilfe geglättete Routenzugfahrpläne erzeugt und optimiert werden können.

Otimização de MIZUSUMASHI

Nos dias de hoje as diferentes indústrias e sectores de atividade económica assentam os seus pilares de desenvolvimento na procura constante de fontes de melhoria, para que assim seja possível melhorar a relação qualidade / preço. Embora no setor industrial as melhorias e inovações tecnológicas surjam a cada dia, estas por si não chegam. Grande parte da otimização incorrida, quer na indústria de manufatura, quer na indústria de serviços, surge da “simples” eliminação de desperdícios, e da procura constante por fontes de melhoria. Com o objetivo traçado, a Grohe Portugal Componentes Sanitários, Lda. propôs a eliminação de desperdícios no âmbito do abastecimento de componentes às linhas de montagem existentes na sua fábrica em Albergaria-a-Velha. Este processo passa não só por uma otimização do tempo de abastecimento e das quantidades de abastecimento, mas também consiste na reestruturação das diferentes rotinas de abastecimento. Todo este processo de otimização estará assente no conceito de Mizusumashi. O Mizusumashi, ou comboio logístico como muitas vezes é referenciado, surge com o objetivo de separar a tarefa de abastecimento da função de montagem. A sua origem surge da adaptação do conceito de Milk Run (volta do leiteiro) à logística interna. Torna-se de relevo referir que, para que este “simples” conceito funcione com uma eficiência que proporcione a sua aplicação, são vastos os fatores que necessitam de ajustamentos ou mesmo, em alguns casos, de uma reestruturação completa. O trabalho desenvolvido nestas instalações fabris, e que culminou neste documento, teve como princípio a análise, avaliação e implementação de melhorias no sistema de abastecimento às linhas de montagem. Todo o processo de abastecimento foi analisado e desconstruído nas suas componentes, para que assim fosse possível desenhar o plano de reestruturação indicado. Foram implementadas melhorias de layout, tempos e tarefas. Os resultados foram positivos tendo em conta o objetivo inicial. Todo este plano foi pensado e documentado com o objetivo de tornar este sistema adaptável a possíveis mudanças. Foi possível então criar um sistema voltado para um plano de melhoria contínua. Com um abastecimento normalizado e rotinado a gestão de stocks é mais precisa diminuindo assim os desperdícios inerentes a estas funções.

Rapid confirmatory method for the determination of sixteen synthetic growth promoters and bisphenol A in bovine milk using dispersive solid-phase extraction and liquid chromatography-tandem mass spectrometry

A rapid liquid chromatographic-tandem mass spectrometric (LC-MS/MS) multi-residue method for the simultaneous quantitation and identification of sixteen synthetic growth promoters and bisphenol A in bovine milk has been developed and validated. Sample preparation was straightforward, efficient and economically advantageous. Milk was extracted with acetonitrile followed by phase separation with NaCl. After centrifugation, the extract was purified by dispersive solid-phase extraction with C18 sorbent material. The compounds were analysed by reversed-phase LC-MS/MS using both positive and negative ionization and operated in multiple reaction monitoring (MRM) mode, acquiring two diagnostic product ions from each of the chosen precursor ions for unambiguous confirmation. Total chromatographic run time was less than 10 min for each sample. The method was validated at a level of 1 mu g L-1. A wide variety of deuterated internal standards were used to improve method performance. The accuracy and precision of the method were satisfactory for all analytes. The confirmative quantitative liquid chromatographic tandem mass spectrometric (LC-MS/MS) method was validated according to Commission Decision 2002/657/EC. The decision limit (CC alpha) and the detection capability (CC beta) were found to be below the chosen validation level of 1 mu g L-1 for all compounds. (C) 2010 Elsevier B.V. All rights reserved.

Reducing fouling during UHT treatment of goat's milk

Whole fresh goat's milk was heat treated at 135 degrees C for 4 s using a miniature UHT plant. The temperature of the milk in the preheating and sterilizer sections, and the milk flow rate were monitored to evaluate the overall heat transfer coefficient (OHTC). The decrease in OHTC was used to estimate the extent of fouling. Goat's milk fouled very quickly and run times of the UHT plant were short. The use of sodium hexametaphosphate, trisodium citrate and cation exchange resins to reduce ionic calcium prior to UHT processing, increased the pH and alcohol stability of the milk and markedly increased the run time of the UHT plant.

Short communication: estimation of the financial benefit of using Jersey milk at different inclusion rates for Cheddar cheese production using partial budgeting

Partial budgeting was used to estimate the net benefit of blending Jersey milk in Holstein-Friesian milk for Cheddar cheese production. Jersey milk increases Cheddar cheese yield. However, the cost of Jersey milk is also higher; thus, determining the balance of profitability is necessary, including consideration of seasonal effects. Input variables were based on a pilot plant experiment run from 2012 to 2013 and industry milk and cheese prices during this period. When Jersey milk was used at an increasing rate with Holstein-Friesian milk (25, 50, 75, and 100% Jersey milk), it resulted in an increase of average net profit of 3.41, 6.44, 8.57, and 11.18 pence per kilogram of milk, respectively, and this additional profit was constant throughout the year. Sensitivity analysis showed that the most influential input on additional profit was cheese yield, whereas cheese price and milk price had a small effect. The minimum increase in yield, which was necessary for the use of Jersey milk to be profitable, was 2.63, 7.28, 9.95, and 12.37% at 25, 50, 75, and 100% Jersey milk, respectively. Including Jersey milk did not affect the quantity of whey butter and powder produced. Althoug further research is needed to ascertain the amount of additional profit that would be found on a commercial scale, the results indicate that using Jersey milk for Cheddar cheese making would lead to an improvement in profit for the cheese makers, especially at higher inclusion rates.

Detection of larvae of Toxocara canis in milk: an experimental study in rabbits.

Toxocariasis, caused most commonly by Toxocara canis, is an important cosmopolitan zoonosis. Paratenic hosts have been employed to provide knowledge regard to the transmission of toxocariasis. Transmammary transmission in murine experimentally infected was observed based on the recovery of larvae from the tissue. The aim of this study was to evaluate the possibility of transmammary transmission of Toxocara canis in rabbits by detecting larvae directly in milk. Seventeen sexually mature virgin white New Zealand female rabbits were divided into two groups. Twelve animals were orally inoculated with 1,000 T. canis embryonated eggs (infected group), and five animals remained uninfected (control group). One month following the infection, the females were mated. Manual collection of 500 ?L of milk from each rabbit was performed on days +7, +14 and +21 of lactation for three consecutive lactations. The recovery of larvae was determined via a centrifuge-sedimentation technique using ether and formalin solutions. ELISA test was run to confirm the production of anti-T. canis antibodies (IgG) by infected rabbits. The presence of larvae was observed in milk samples from 5 (41.7%) of the 12 infected rabbits. The total number of recovered larvae was 20, ranging from 1 to 4 larvae per lactation/rabbit. Larvae were recovered exclusively on days 7 and 14 of lactation. Recovery was verified in different lactations. No significant difference was observed with respect to the number of larvae either in the same lactation period or in different lactation periods. Anti-T. canis antibodies were detected in all infected rabbits. In conclusion, the presence of larvae in rabbit milk samples suggests the possibility of galactogenic transmission of T. canis in paratenic hosts. Moreover, the technique employed in this study allows for the recovery of larvae directly from milk.

Methods of detecting fouling caused by heating of milk

Fouling is the deposition of milk solids on heat transfer sur aces, particularly heat exchangers. It is a major industrial problem, which causes a decrease in heat transfer efficiency and shortens run times. The resultant effect is a decrease in process efficiency and economy. For studying and monitoring deposit formation, suitable fouling detectors or methods of measuring the deposit are required. This can be achieved through direct means, whereby the deposit is analyzed after a certain time, or indirectly through instrumentation for monitoring parameters such as temperature, pressure, flow rate, overall heat transfer coefficient, heat flux, and other physical properties. This article reviews the various reported fouling detection methods.

MiLK: Transforming everyday places into dynamic learning spaces with mobile and web technologies

This paper explores how game authoring tools can teach processes that transform everyday places into engaging learning spaces. It discusses the motivation inherent in playing games and creating games for others, and how this stimulates an iterative process of creation and reflection and evokes a natural desire to engage in learning. The use of MiLK at the Adelaide Botanic Gardens is offered as a case in point. MiLK is an authoring tool that allows students and teachers to create and share SMS games for mobile phones. A group of South Australian high school students used MiLK to play a game, create their own games and play each other’s games during a day at the gardens. This paper details the learning processes involved in these activities and how the students, without prompting, reflected on their learning, conducted peer assessment, and engaged in a two-way discussion with their teacher about new technologies and their implications for learning. The paper concludes with a discussion of the needs and requirements of 21st century learners and how MiLK can support constructivist and connectivist teaching methods that engage learners and will produce an appropriately skilled future workforce.

MILK : the Mobile Informal Learning Kit. Collaborating to design successful mobile learning applications

This paper suggests ways for educators and designers to understand and merge priorities in order to inform the development of mobile learning (m-learning) applications that maximise user experiences and hence learning opportunities. It outlines a User Experience Design (UXD) theory and development process that requires designers to conduct a thorough initial contextual inquiry into a particular domain in order to set project priorities and development guidelines. A matrix that identifies the key contextual considerations namely the social, cultural, spatial, technical and temporal constructs of any domain is presented as a vital tool for achieving successful UXD. The frame of reference provided by this matrix ensures that decisions made throughout the design process are attributable to a desired user experience. To illustrate how the proposed UXD theory and development process supports the creation of effective m-learning applications, this paper documents the development process of MILK (Mobile Informal Learning Kit). MILK is a support tool that allows teachers and students to develop event paths that consist of a series SMS question and answer messages that lead players through a series of checkpoints between point A and point B. These event paths can be designed to suit desired learning scenarios and can be used to explore a particular place or subject. They can also be designed to facilitate formal or informal learning experiences.

Prags Boulevard in Copenhagen : from run-down strip to boulevard

Prags Boulevard will form a 2km long pedestrian spine running east-west between the historic cities of Copenhagen and Amager. It is located on a some-what run down site, which accommodated illicit functions such as casual drug use and drinking, as well as sheds for squatters. The renovation of this site by the city of Copenhagen forms part of the Holmbladsgade renovation project, and a two-phase competition was held in 2001 to develop a green area and meeting place, transforming it into a place that residents would want to visit rather than avoid. The designer, local landscape architect Kristine Jensens recognises that though the site is linear it ‘has no traffic importance’, though as she notes ‘we like the project because it runs straight east west from the city pulse to the water of Oresund’. In developing the project, she has attempted to allow it to ‘run parallel’ to its existing illicit uses, using a ‘light touch’ of insertions. While it would be hard to describe the project as truly light in its touch (graphically, it is a very bold scheme), there is no doubt that it is parallel: in terms of use it runs alongside rather than against existing uses; in terms of its type it’s all about length, like a boulevard, although it clearly differs from a boulevard in other respects.

Concentrations of polybrominated diphenyl ethers (PBDEs) in matched samples of human milk, dust and indoor air

Polybrominated diphenyl ethers (PBDEs) are lipophilic, persistent pollutants found worldwide in environmental and human samples. Exposure pathways for PBDEs remain unclear but may include food, air and dust. The aim of this study was to conduct an integrated assessment of PBDE exposure and human body burden using 10 matched samples of human milk, indoor air and dust collected in 2007–2008 in Brisbane, Australia. In addition, temporal analysis was investigated comparing the results of the current study with PBDE concentrations in human milk collected in 2002–2003 from the same region. PBDEs were detected in all matrices and the median concentrations of BDEs -47 and -209 in human milk, air and dust were: 4.2 and 0.3 ng/g lipid; 25 and 7.8 pg/m3; and 56 and 291 ng/g dust, respectively. Significant correlations were observed between the concentrations of BDE-99 in air and human milk (r = 0.661, p = 0.038) and BDE-153 in dust and BDE-183 in human milk (r = 0.697, p = 0.025). These correlations do not suggest causal relationships — there is no hypothesis that can be offered to explain why BDE-153 in dust and BDE-183 in milk are correlated. The fact that so few correlations were found in the data could be a function of the small sample size, or because additional factors, such as sources of exposure not considered or measured in the study, might be important in explaining exposure to PBDEs. There was a slight decrease in PBDE concentrations from 2002–2003 to 2007–2008 but this may be due to sampling and analytical differences. Overall, average PBDE concentrations from these individual samples were similar to results from pooled human milk collected in Brisbane in 2002–2003 indicating that pooling may be an efficient, cost-effective strategy of assessing PBDE concentrations on a population basis. The results of this study were used to estimate an infant's daily PBDE intake via inhalation, dust ingestion and human milk consumption. Differences in PBDE intake of individual congeners from the different matrices were observed. Specifically, as the level of bromination increased, the contribution of PBDE intake decreased via human milk and increased via dust. As the impacts of the ban of the lower brominated (penta- and octa-BDE) products become evident, an increased use of the higher brominated deca-BDE product may result in dust making a greater contribution to infant exposure than it does currently. To better understand human body burden, further research is required into the sources and exposure pathways of PBDEs and metabolic differences influencing an individual's response to exposure. In addition, temporal trend analysis is necessary with continued monitoring of PBDEs in the human population as well as in the suggested exposure matrices of food, dust and air.