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Systemic Constellations are a phenomenological approach to resolving personal, professional and organizational issues. They offer a way of mapping a present reality, working at the source of the hidden dynamics and moving to a resolution. This systemic approach often delivers surprising and unexpected insights while also offering the possibility to analyze and solve organizational problems. Rational analysis provides the whole picture of the problem which often turns out to be too complex for a decision making. Systemic constellations can help to simplify and clarify the situation and inform what has to happen next [8], [17]. The outcomes of systemic constellations as an additional resource for solving comprehensive technical problems have not yet been sufficiently investigated. In structural constellation work dealing with technical problems, the individuals who are involved in the problem situation are used to represent different system components, substances or fields. A moderator voices the feedback from the representatives concerning their feelings or intuitive movements, and points to possible solutions. For example, a moderator places the representatives somewhere in the room, develops a three-dimensional picture of the constellation of the analyzed situation and tries to expose the factors empowering or blocking the way towards constructive solutions [13]. This paper explores the theoretical background and practical outcomes of the systemic constellation method for technical problem solving. It presents some case study work which has been conducted in recent years, and then discusses its findings and implications. The research outlined in this paper demonstrates that the noteworthy contribution of structural constellation work for problem solving is typically the result of a combination of functional analysis and the feeling-as-information principle. The constellation work helps, at first, to reveal the subjective experiences, such as feelings, moods, emotions, and bodily sensations, and then to accept them as a source of objective information relevant to the decision making process. In accordance with the latest research [19], the use of feelings as a source of information follows the same principles as the use of any other information. This paper provides the structures of some standard templates and types of constellation work for technical problems, and discusses the preconditions for their application.
The effective executing innovation projects requires multiple estimation of market success of new product features in the early stages of customer-centered innovation process such as strategy formulation, evaluation of ideas and concepts and also at a stage close to the market launch. The attempts to integrate customers for estimation of the market success often result in time-consuming customer interviews or lengthy field research. For this reason, industrial companies usually try to skip customer surveys even if they risk that their innovations will fail to bring the anticipated economic outcomes. In many practical cases, the customer surveys are simply not feasible or too expensive. As a result, the internal assessments within companies are frequently the only resource available in innovation process in the industrial environment. The paper discusses the possibilities of the fast identification of promising innovation opportunities and new product features based on the internal competences of companies. It compares the results of customer surveys with the estimation of internal company-experts and analyses the accuracy and validity of the expert assessments. The presented case studies demonstrate the accuracy rate between 43% and 77% for prediction of new product features with high market potential by company-internal experts. The paper proposes the evaluation methods to increase the accuracy rate and outlines that one of the essential requirements for reliable forecasting by the experts is their profound understanding of the customer working process, the ability to estimate the importance of customer needs and to assess the level of customer satisfaction with current products on the market.
Pure component sorption isotherms of n-butane, isobutane, 1-butene and isobutene on the metal–organic framework (MOF) 3∞[Cu4(μ4-O)(μ2-OH)2(Me2trz-pba)4] at various temperatures between 283 K and 343 K and pressures up to 300 kPa are presented. The isotherms show a stepwise pore filling which is typical for structurally flexible materials with broad adsorption–desorption hysteresis loops. Gate opening pressures in their endemic characteristic depend on the used hydrocarbon gases. From all investigated gases only the isotherms of 1-butene present a second step at a relative pressure above p/p0 = 0.55. As a consequence, only 1-butene can fully open the framework resulting in a pore volume of 0.54 cm3 g−1. This result is in good agreement with the value of 0.59 cm3 g−1 calculated based on single crystal structure data. The isosteric heat of adsorption was calculated from the experimental isotherms for all C4-isomers. At low loadings the isosteric heat is in a narrow region between 41 and 49 kJ mol−1. Moreover, in situ XRD measurements at different relative hydrocarbon pressures were performed at 298 K for the C4-isomers. The differences in the pressure-depending powder diffraction patterns indicate phase transitions as a result of adsorption. Similar diffraction patterns were observed for all C4-hydrocarbons, except 1-butene, where the second step at higher relative pressure (p/p0 > 0.55) is accompanied by an additional phase transition. This powder pattern resembles that of the as-synthesized MOF material containing solvent molecules in the pore system. The resulting structural changes of the material during guest and pressure induced external stimuli are evidenced by the new coupled XRD adsorption equipment.
A series of isostructural 3D coordination polymers (3)∞[M(tdc)(bpy)] (M(2+) = Zn(2+), Cd(2+), Co(2+), Fe(2+); tdc(2-) = 2,5-thiophenedicarboxylate; bpy = 4,4'-bipyridine) was synthesized and characterized by X-ray diffraction, thermal analysis, and gas adsorption measurements. The materials show high thermal stability up to approximately 400 °C and a solvent induced phase transition. Single crystal X-ray structure determination was successfully performed for all compounds after the phase transition. In the zinc-based coordination polymer, various amounts of a second type of metal ions such as Co(2+) or Fe(2+) could be incorporated. Furthermore, the catalytic behavior of the homo- and heteronuclear 3D coordination polymers in an oxidation model reaction was investigated.
In 35 deutschen und 7 europäischen Büro- und Verwaltungsgebäuden wurden auf Basis von Monitoringkampagnen über mehrere Betriebsjahre Raum- und Außentemperaturwerte in zeitlich hoher Auflösung erfasst und der thermische Raumkomfort im Sommer standardisiert nach der Komfortnorm DIN EN 15251:2007-08 detailliert ausgewertet. Ergänzt wird die Auswertung um Kurzzeitmesskampagnen über zwei sehr warme Wochen im Sommer in unsanierten bzw. teilsanierten Bürogebäuden, errichtet im Zeitraum von 1960 bis 1975. Die untersuchten Gebäude mit ihrem jeweiligen Kühlkonzept lassen sich in sechs Kategorien einteilen: ohne Kühlung, passive, luftgeführte und wassergeführte Kühlung sowie Mixed-mode-Kühlung und Vollklimatisierung. Im Quervergleich aller Gebäude werden die Kühlkonzepte gleichermaßen nach dem thermischen Raumkomfort und thermischen Kühlenergiebezug bewertet. Detaillierte Komfortuntersuchungen nach der Europäischen Komfortnorm DIN EN 15251:2007-08 geben Hinweise auf die Wirksamkeit der eingesetzten Kühltechnologien in den jeweiligen Klimazonen. Daraus lassen sich Handlungsempfehlungen für die Planungspraxis und den Gebäudebetrieb ableiten.
Mit längerfristigen Nutzerbefragungen in zwei unmittelbar benachbarten Bürogebäuden in Freiburg wurden das Temperaturempfinden der Nutzer und deren Zufriedenheit mit dem thermischen Raumkomfort zweimal täglich erfasst. Ein Bürogebäude wird im Sommer mit einem maschinellen Nachtlüftungskonzept konditioniert und das zweite verfügt über eine Betonkerntemperierung und eine Zu‐ und Abluftanlage. Auf Basis der vorhandenen Daten aus der Erhebung wurde mit Hilfe von Regressionsanalysen ein Modell zur Vorhersage der Komforttemperatur berechnet und mit den Modellen in DIN EN 15251 verglichen.
The durability of polymer electrolyte membrane fuel cells (PEMFC) is governed by a nonlinear coupling between system demand, component behavior, and physicochemical degradation mechanisms, occurring on timescales from the sub-second to the thousand-hour. We present a simulation methodology for assessing performance and durability of a PEMFC under automotive driving cycles. The simulation framework consists of (a) a fuel cell car model converting velocity to cell power demand, (b) a 2D multiphysics cell model, (c) a flexible degradation library template that can accommodate physically-based component-wise degradation mechanisms, and (d) a time-upscaling methodology for extrapolating degradation during a representative load cycle to multiple cycles. The computational framework describes three different time scales, (1) sub-second timescale of electrochemistry, (2) minute-timescale of driving cycles, and (3) thousand-hour-timescale of cell ageing. We demonstrate an exemplary PEMFC durability analysis due to membrane degradation under a highly transient loading of the New European Driving Cycle (NEDC).