Application System (application + system)

Distribution by Scientific Domains


Selected Abstracts


Knowledge management and decision support for electrical power utilities

KNOWLEDGE AND PROCESS MANAGEMENT: THE JOURNAL OF CORPORATE TRANSFORMATION, Issue 4 2001
G. M. West
This paper describes a case study for a knowledge management project carried out in conjunction with two major UK electrical utilities. The focus of the work is on the design of protection schemes for electrical power transmission systems. A brief overview is provided of the traditional protection system design processes implemented within both companies and the associated shortcomings relating to the management of the data, information and knowledge throughout this process. The development of the Design Engineering Knowledge Application System (DEKAS), designed to address the knowledge management issues within both companies, is described, and the perceived benefits this system offers the existing protection design and application process of each company will be discussed. Copyright © 2001 John Wiley & Sons, Ltd. [source]


Generation of a virtual reality-based automotive driving training system for CAD education

COMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 2 2009
Janus Liang
Abstract Designing and constructing a virtual reality-based system is useful for educating students about scenario planning, geometric modeling and computer graphics. In particular, students are exposed to the practical issues surrounding topics such as geometric modeling, rendering, collision detection, model animation and graphical design. Meanwhile, building an application system provides students exposure to the real-world side of software engineering that they are typically shielded from in the traditional computer class. This study is a description of the experiences with instructing "Computer-aided Industrial design" and "OOP," two introductory classes that focus on designing and generating the VR based system possible in the course of a semester and then "VR System," an advanced course in the next semester. This study emphasizes the continuing evolution in the training and educational needs of students of CAD-systems. This study breaks down an automobile driving training system into different components that are suitable for individual student projects and discusses the use of modern graphical design tools such as 3ds MAX for artistic design in this system. The conclusion of this study proposes a rough schedule for developing a VR based system during the course of a semester and an overview is given of a concept of a virtual reality-based design and constructing system that is being developed. © 2008 Wiley Periodicals, Inc. Comput Appl Eng Educ 17: 148,166, 2009; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae20178 [source]


The molecular receptive range of an olfactory receptor in vivo (Drosophila melanogaster Or22a)

DEVELOPMENTAL NEUROBIOLOGY, Issue 14 2006
Daniela Pelz
Abstract Understanding how odors are coded within an olfactory system requires knowledge about its input. This is constituted by the molecular receptive ranges (MRR) of olfactory sensory neurons that converge in the glomeruli of the olfactory bulb (vertebrates) or the antennal lobe (AL, insects). Aiming at a comprehensive characterization of MRRs in Drosophila melanogaster we measured odor-evoked calcium responses in olfactory sensory neurons that express the olfactory receptor Or22a. We used an automated stimulus application system to screen [Ca2+] responses to 104 odors both in the antenna (sensory transduction) and in the AL (neuronal transmission). At 10,2 (vol/vol) dilution, 39 odors elicited at least a half-maximal response. For these odorants we established dose-response relationships over their entire dynamic range. We tested 15 additional chemicals that are structurally related to the most efficient odors. Ethyl hexanoate and methyl hexanoate were the best stimuli, eliciting consistent responses at dilutions as low as 10,9. Two substances led to calcium decrease, suggesting that Or22a might be constitutively active, and that these substances might act as inverse agonists, reminiscent of G-protein coupled receptors. There was no difference between the antennal and the AL MRR. Furthermore we show that Or22a has a broad yet selective MRR, and must be functionally described both as a specialist and a generalist. Both these descriptions are ecologically relevant. Given that adult Drosophila use approximately 43 ORs, a complete description of all MRRs appears now in reach. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006 [source]


Molecular analysis of the A322D mutation in the GABAA receptor ,1 -subunit causing juvenile myoclonic epilepsy

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2005
Klaus Krampfl
Abstract Juvenile myoclonic epilepsy (JME) belongs to the most common forms of hereditary epilepsy, the idiopathic generalized epilepsies. Although the mode of inheritance is usually complex, mutations in single genes have been shown to cause the disease in some families with autosomal dominant inheritance. The first mutation in a multigeneration JME family has been recently found in the ,1 -subunit of the GABAA receptor (GABRA1), predicting the single amino acid substitution A322D. We further characterized the functional consequences of this mutation by coexpressing ,1 -, ,2 - and ,2 -subunits in human embryonic kidney (HEK293) cells. By using an ultrafast application system, mutant receptors have shown reduced macroscopic current amplitudes at saturating GABA concentrations and a highly reduced affinity to GABA compared to the wild-type (WT). Dose,response curves for current amplitudes, activation kinetics, and GABA-dependent desensitization parameters showed a parallel shift towards 30- to 40-fold higher GABA concentrations. Both deactivation and resensitization kinetics were considerably accelerated in mutant channels. In addition, mutant receptors labelled with enhanced green fluorescent protein (EGFP) were not integrated in the cell membrane, in contrast to WT receptors. Therefore, the A322D mutation leads to a severe loss-of-function of the human GABAA receptor by several mechanisms, including reduced surface expression, reduced GABA-sensitivity, and accelerated deactivation. These molecular defects could decrease and shorten the resulting inhibitory postsynaptic currents (IPSCs) in vivo, which can induce a hyperexcitability of the postsynaptic membrane and explain the occurrence of epileptic seizures. [source]


Mechanotransduction of bovine articular cartilage superficial zone protein by transforming growth factor , signaling

ARTHRITIS & RHEUMATISM, Issue 11 2007
Corey P. Neu
Objective Mechanical signals are key determinants in tissue morphogenesis, maintenance, and restoration strategies in regenerative medicine, although molecular mechanisms of mechanotransduction remain to be elucidated. This study was undertaken to investigate the mechanotransduction process of expression of superficial zone protein (SZP), a critical joint lubricant. Methods Regional expression of SZP was first quantified in cartilage obtained from the femoral condyles of immature bovines, using immunoblotting, and visualized by immunohistochemistry. Contact pressure mapping in whole joints was accomplished using pressure-sensitive film and a load application system for joint testing. Friction measurements on cartilage plugs were acquired under boundary lubrication conditions using a pin-on-disk tribometer modified for reciprocating sliding. Direct mechanical stimulation by shear loading of articular cartilage explants was performed with and without inhibition of transforming growth factor , (TGF,) signaling, and SZP content in media was quantified by enzyme-linked immunosorbent assay. Results An unexpected pattern of SZP localization in knee cartilage was initially identified, with anterior regions exhibiting high levels of SZP expression. Regional SZP patterns were regulated by mechanical signals and correlated with tribological behavior. Direct relationships were demonstrated between high levels of SZP expression, maximum contact pressures, and low friction coefficients. Levels of SZP expression and accumulation were increased by applying shear stress, depending on location within the knee, and were decreased to control levels with the use of a specific inhibitor of TGF, receptor type I kinase and subsequent phospho-Smad2/3 activity. Conclusion These findings indicate a new role for TGF, signaling in the mechanism of cellular mechanotransduction that is especially significant for joint lubrication. [source]


Virtuelle Produktmodellierung am Beispiel eines Pumpenlaufrades

CHEMIE-INGENIEUR-TECHNIK (CIT), Issue 1-2 2003
F.-K. Benra Dr.-Ing.
Abstract Durch die Verkürzung der Produktlebenszyklen werden die zur Verfügung stehenden Entwicklungszeiten entscheidend eingeschränkt. Es bleibt keine Zeit mehr für ein umfangreiches Erprobungsprogramm, bei dem die gewünschten Produkteigenschaften durch die Untersuchung und Abwandlung diverser Prototypen erzielt werden. Durch konsequenten Einsatz virtueller Techniken ist die Simulation der geforderten Produkteigenschaften und des Herstellungsprozesses möglich. Das Ergebnis einer so aufgebauten CAx-Prozesskette ist eine vollständige, durchgängig rechnerintegrierte Bauteilentwicklung. In diesem Beitrag wird ein derartiger Produktentstehungsprozess am Beispiel eines Kreiselpumpenlaufrades detailliert beschrieben. Durch die Schaffung eines Anwendungssystems für die Berechnung, Konstruktion und Fertigung von Pumpenlaufrädern lässt sich der Entwicklungsprozess enorm verkürzen. Gleichzeitig ist damit eine wesentliche Senkung der Entwicklungskosten für ein äußerst effektives und zuverlässiges Produkt verbunden. Virtual Modeling of Products with a Centrifugal Pump Impeller as an Example Shortening of the product life cycles means less time for the development of a technical product. There is no more time for an extensive testing program to obtain the desired product properties by investigation and modification of various prototypes. By careful application of virtual techniques the simulation of the required product properties and the production process is possible. The result of a CAx-System is a complete computer-integrated construction unit development. In this contribution the product developing process is described in detail for a centrifugal pump impeller. The creation of an application system for the computation, construction and manufacturing of pump impellers shortens the development process enormously. At the same time the development costs for an extremely effective and reliable product become substantially lower. [source]


Towards workflow simulation in service-oriented architecture: an event-based approach

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 4 2008
Yanchong Zheng
Abstract The emergence of service-oriented architecture (SOA) has brought about a loosely coupled computing environment that enables flexible integration and reuse of heterogeneous systems. On building a SOA for application systems, more and more research has been focused on service composition, in which workflow and simulation techniques have shown great potential. Simulation of services' interaction is important since the services ecosystem is dynamic and in continuous evolution. However, there is a lack in the research of services' simulation, especially models, methods and systems to support the simulation of interaction behavior of composite services. In this paper, an enhanced workflow simulation method with the support of interactive events mechanism is proposed to fulfill this requirement. At build time, we introduce an event sub-model in the workflow meta-model, and our simulation engine supports the event-based interaction pattern at run time. With an example simulated in the prototype system developed according to our method, the advantages of our method in model verification and QoS evaluation for service compositions are also highlighted. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Strategies to Improve the Use Efficiency of Mineral Fertilizer Nitrogen Applied to Winter Wheat

JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 3 2002
K. Blankenau
Recovery of fertilizer nitrogen (N) applied to winter wheat crops at tillering in spring is lower than that of N applied at later growth stages because of higher losses and immobilization of N. Two strategies to reduce early N losses and N immobilization and to increase N availability for winter wheat, which should result in an improved N use efficiency (= higher N uptake and/or increased yield per unit fertilizer N), were evaluated. First, 16 winter wheat trials (eight sites in each of 1996 and 1997) were conducted to investigate the effects of reduced and increased N application rates at tillering and stem elongation, respectively, on yield and N uptake of grain. In treatment 90-70-60 (90 kg N ha,1 at tillering, 70 kg N ha,1 at stem elongation and 60 kg N ha,1 at ear emergence), the average values for grain yield and grain N removal were up to 3.1 and 5.0 % higher than in treatment 120-40-60, reflecting conventional fertilizer practice. Higher grain N removal for the treatment with reduced N rates at tillering, 90-70-60, was attributed to lower N immobilization (and N losses), which increased fertilizer N availability. Secondly, as microorganisms prefer NH4+ to NO3, for N immobilization, higher net N immobilization would be expected after application of the ammonium-N form. In a pot experiment, net N immobilization was higher and dry matter yields and crop N contents at harvest were lower with ammonium (ammonium sulphate + nitrification inhibitor Dicyandiamide) than with nitrate (calcium nitrate) nutrition. Five field trials were then conducted to compare calcium nitrate (CN) and calcium ammonium nitrate (CAN) nutrition at tillering, followed by two CAN applications for both treatments. At harvest, crop N and grain yield were higher in the CN than in the CAN treatment at each N supply level. In conclusion, fertilizer N use efficiency in winter wheat can be improved if N availability to the crops is increased as a result of reduced N immobilization (and N losses) early in the growth period. N application systems could be modified towards strategies with lower N applications at tillering compensated by higher N dressing applications later. An additional advantage is expected to result from use of nitrate-N fertilizers at tillering. Strategien zur Verbesserung der Effizienz von Düngerstickstoff in Winterweizen Aus früheren Versuchen mit Winterweizen ist bekannt, daß zur Ernte die Wiederfindung von im Frühjahr zur Bestokkung gedüngtem Stickstoff (N) geringer ist, als die von N aus Spätgaben. Die Ursachen liegen in einer höheren mikrobiell-bedingten Netto-N-Immobilisation, aber auch N-Verlusten zwischen Bestockung und Schoßbeginn im Vergleich zu späteren Wachstumstadien begründet. In den vorliegenden Versuchen wurden zwei Strategien getestet, um insbesondere die früh in der Vegetation auftretende Netto-N-Immobilisation zu vermindern. Die dadurch erwartete erhöhte N-Verfügbarkeit sollte zu einer erhöhten N-Effizienz (höherer N-Entzug/Ertrag bezogen auf die N-Düngung) führen. 1996 und 1997 wurden jeweils 8 Feldversuche mit Winterweizen durchgeführt, um den Einfluß einer reduzierten Andüngung bei gleichzeitig erhöhter Schossergabe im Vergleich zur konventionellen N-Düngung zu untersuchen. Tatsächlich wurden in dem Prüfglied 90-70-60 (N-Sollwertdüngung: 90 kg N ha,1, Schossergabe: 70 kg N ha,1, Ährengabe: 60 kg N ha,1) im Mittel bis zu 3.1 % höhere Erträge und 5.0 % höhere N-Abfuhren mit dem Korn im Vergleich zur konventionellen Variante 120-40-60 (N-Sollwertdüngung: 120 kg N ha,1, Schossergabe: 40 kg N ha,1 und Ährengabe: 60 kg N ha,1) erzielt. Die höhere N-Abfuhr kann auf eine erhöhte N-Verfügbarkeit infolge geringerer mikrobieller N-Festlegung zurückgeführt werden. Da die vornehmlich heterotrophen Bodenmikroorganismen bevorzugt NH4+ gegenüber NO3, immobilisieren, kann eine höhere N-Immobilisation bei Ammonium-Düngung erwartet werden. Tatsächlich wurden in einem Gefäßversuch nach Düngung von Ammoniumsulfat (+ Nitrifikationshemmer Dicyandiamid) geringere Trokkenmasseerträge und N-Aufnahmen von Weizenpflanzen erzielt als mit Calciumnitrat. Für die Ammoniumsulfatvariante ergab sich eine höhere Netto-N-Immobilisation. Danach wurde in fünf Feldversuchen mit Winterweizen der Einfluß einer Andüngung mit Nitrat (Calciumnitrat) im Vergleich zur Verwendung des ammoniumhaltigen Kalkammonsalpeters (KAS) auf die N-Aufnahme und den Kornertrag untersucht (beide Varianten erhielten KAS als Spätgaben). In der nitratangedüngten Variante wurden zum Teil signifikant höhere Ertäge und N-Aufnahmen in Korn und Stroh ermittelt. Aus den dargestellten Versuchen kann gefolgert werden, daß die Düngerstickstoff-Effizienz verbessert werden kann, wenn vor allem die N-Immobilisation (und eventuell auch N-Verluste) in frühen Wachstumsstadien zwischen Bestockung und Schoßbeginn verringert und so die N-Verfügbarkeit erhöht wird. Es kann empfohlen werden Winterweizenbestände mit geringeren N-Mengen , als nach N-Sollwert 120 kg N ha,1 vorgesehen , anzudüngen und die Schossergabe entsprechend zu erhöhen. Die Verwendung von nitrathaltigen Düngern bei der Andüngung ist von Vorteil. [source]


Functional and morphological comparison of three primary liver cell types cultured in the AMC bioartificial liver

LIVER TRANSPLANTATION, Issue 4 2007
Paul P.C. Poyck
The selection of a cell type for bioartificial liver (BAL) systems for the treatment of patients with acute liver failure is in part determined by issues concerning patient safety and cell availability. Consequently, mature porcine hepatocytes (MPHs) have been widely applied in BAL systems. The success of clinical BAL application systems is, however, largely dependent on the functionality and stability of hepatocytes. Therefore, we compared herein the general metabolic and functional activities of MPHs with mature human hepatocytes (MHHs) in the Academic Medical Center (AMC)-BAL during a 7-day culture period. We also tested fetal human hepatocytes (FHHs), since their proliferation capacity is higher than MHHs and their function is increased compared to human liver cell lines. The results showed large differences between the 3 cell types. MHHs eliminated 2-fold more ammonia and produced 3-fold more urea than MPHs, whereas FHHs produced ammonia. Lidocaine elimination of FHHs was 3.5-fold higher than MPHs and 6.6-fold higher than of MHHs. Albumin production was not different between the 3 cell types. MPHs and FHHs became increasingly glycolytic, whereas MHHs remained metabolically stable during the whole culture period. MHHs and MPHs formed tissue-like structures inside the AMC-BAL. In conclusion, we propose that FHHs can be considered as a suitable cell type for pharmacological studies inside a bioreactor. However, we conclude that MHHs are the preferred cell source for loading a BAL device for clinical use, because of their high ammonia eliminating capacity and metabolic stability. MPHs should be considered as the best alternative cell source for BAL application, although their phenotypic instability urges application within 1 or 2 days after loading. Liver Transpl 13:589,598, 2007. © 2007 AASLD. [source]