Search results for "Operation"
showing 10 items of 2969 documents
Zur Bestimmung der wirtschaftlichen Bestellmenge bei Preisstaffeln
1970
Es wird ein analytisches Verfahren zur Berechnung der wirtschaftlichen Bestellmenge unter Berucksichtigung einer Mengen-Preis-Staffel beschrieben. Wahrend man bei der klassischen Losung dieses Problems zu vorgegebenem Bedarfiterativ den gunstigsten Preisnachlas bestimmt, wird bei dieser Methode gefragt, fur welchen Jahresbedarfsbereich ein vorgegebener Rabatt optimal ist. Aus dieser Fragestellung heraus kann eine Tabelle entwickelt werden, der die wirtschaftlichen Bestellmengen unmittelbar zu entnehmen sind. Das Verfahren eignet sich besonders zur Behandlung gleichartiger Produkte, deren Preis sich nach derselben Mengen-Preis-Staffel richtet.
Die Anwendung der Dynamischen Optimierung bei der Sozial-Sanitären Bezirkseinteilung
1979
Nach einer kurzen Analyse des Problems der optimalen Aufteilung eines geographischen Gebietes in sozial-sanitare Bezirke wird in der vorliegenden Arbeit fur die Losung eines solchen Problems ein Modell dynamischer Programmierung verwendet. Es werden dann zwei Algorithmen vorgeschlagen: der erste, der von der territorialen Einheit ausgeht, soll die zulassigen sozial-sanitaren Bezirke unter Berucksichtigung der Faktoren Nahe, Dichte und begrenzter Bevolke-rungsunterschied ermitteln; der zweite errechnet jene Gesamtheit der zulassigen Bezirke, die, jede territoriale Einheit nur einmal „deckend“, eine Zielfunktion auf ein Minimum reduziert, die das Gleichgewicht zwischen Angebot und Nachfrage d…
Die Methode der „direkten Koeffizientenanpassung“ (μ-Form) des Separable Programming
1970
Zur approximativen Losung von Optimierungsproblemen mit trennbaren nichtlinearen Funktionen (Separable Programming) werden haufig modifizierte Methoden der linearen Planungsrechnung verwendet. Dabei ersetzt man die nichtlinearen Funktionen durch lineare Streckenzuge. Fur diese polygonale Approximation werden in der Literatur die sog.λ-Form und die sog.δ-Form vorgeschlagen, die jedoch eine aufwendige Datenorganisation erfordern. In diesem Beitrag soll eine kompaktere Organisationsform (μ-Form) vorgeschlagen werden. Zu ihrer Durchfuhrung werden die Rechenregeln der Upper-Bounding-Technique und die Regeln zur nachtraglichen Anderung von Matrixelementen verwendet. Der Vorteil gegenuber derλ-For…
Improving the Representativeness of a Simple Random Sample: An Optimization Model and Its Application to the Continuous Sample of Working Lives
2020
This paper proposes an optimization model for selecting a larger subsample that improves the representativeness of a simple random sample previously obtained from a population larger than the population of interest. The problem formulation involves convex mixed-integer nonlinear programming (convex MINLP) and is, therefore, NP-hard. However, the solution is found by maximizing the size of the subsample taken from a stratified random sample with proportional allocation and restricting it to a p-value large enough to achieve a good fit to the population of interest using Pearson&rsquo
Inventory record inaccuracy in supply chains: the role of workers' behavior
2014
Purpose – The purpose of this paper is to explore the effect of inventory record inaccuracy due to behavioral aspects of workers on the order and inventory variance amplification. Design/methodology/approach – The authors adopt a continuous-time analytical approach to describe the effect of inbound throughput on the inventory and order variance amplification due to the workload pressure and arousal of workers. The model is numerically solved through simulation and results are analyzed with statistical general linear model. Findings – Inventory management policies that usually dampen variance amplification are not effective when inaccuracy is generated due to workers’ behavioral aspects. Sp…
Basis for a general theory of organizations
2011
Purpose – The purpose of this paper is to identify the conceptual basis shared by different theories, regardless of the unit of analysis they specifically adopt. The different ontological choice (or different segment of reality studied by each theory) does not hinder conceptual common ground for a good number of organisational theories.Design/methodology/approach – The paper highlights the importance of hierarchical, social and institutional relations and of the technological, cognitive, social and institutional contents. It looks at the common conceptual contents of the two main theories examined, and those of a wide set of other theories addressed here. Both of the theories examined are i…
An Innovative Structural Dynamic Identification Procedure Combining Time Domain OMA Technique and GA
2022
In this paper an innovative and simple Operational Modal Analysis (OMA) method for structural dynamic identification is proposed. It combines the recently introduced Time Domain–Analytical Signal Method (TD–ASM) with the Genetic Algorithm (GA). Specifically, TD–ASM is firstly employed to estimate a subspace of candidate modal parameters, and then the GA is used to identify the structural parameters minimizing the fitness value returned by an appropriately introduced objective function. Notably, this method can be used to estimate structural parameters even for high damping ratios, and it also allows one to identify the Power Spectral Density (PSD) of the structural excitat…
Diseased Social Predators
2017
Social predators benefit from cooperation in the form of increased hunting success, but may be at higher risk of disease infection due to living in groups. Here, we use mathematical modeling to investigate the impact of disease transmission on the population dynamics benefits provided by group hunting. We consider a predator-prey model with foraging facilitation that can induce strong Allee effects in the predators. We extend this model by an infectious disease spreading horizontally and vertically in the predator population. The model is a system of three nonlinear differential equations. We analyze the equilibrium points and their stability as well as one- and two-parameter bifurcations. …
EULAR/PRINTO/PRES criteria for Henoch-Schonlein purpura, childhood polyarteritis nodosa, childhood Wegener granulomatosis and childhood Takayasu arte…
2010
EULAR/PRINTO/PRES Objectives To validate the previously proposed classification criteria for Henoch-Schonlein purpura (HSP), childhood polyarteritis nodosa (c-PAN), c-Wegener granulomatosis (c-WG) and c-Takayasu arteritis (c-TA).Methods Step 1: retrospective/prospective webdata collection for children with HSP, c-PAN, c-WG and c-TA with age at diagnosis <= 18 years. Step 2: blinded classification by consensus panel of a representative sample of 280 cases. Step 3: statistical (sensitivity, specificity, area under the curve and.-agreement) and nominal group technique consensus evaluations.Results 827 patients with HSP, 150 with c-PAN, 60 with c-WG, 87 with c-TA and 52 with c-other were compar…
Report of the European DNA profiling group (EDNAP)-an investigation of the hypervariable STR loci ACTBP2, APOAI1 and D11S554 and the compound loci D1…
1999
This paper describes the results of three collaborative exercises which continues the EDNAP theme to explore whether uniformity of DNA profiling results could be achieved between European laboratories using STRs. In an earlier exercise, complex hypervariable AAAG-repeat STR loci were investigated, but reproducibility was found to be poor because of the variation of techniques used by participating laboratories. In the exercise reported here, an internal allelic ladder composed of ACTBP2 and D11S554 fragments was distributed. This ladder was used to size ACTBP2 analysed by a "singleplex" PCR amplification and D11S554 combined with APOAI1 in a separate "duplex" reaction. Laboratories were ask…