Toward the incorporation of temporal interaction analysis techniques in modeling and understanding sociotechnical systems

The increased complexity of modern sociotechnical systems (STS) necessitates the need for a manageable representation of their attributes, to augment our understanding and enable the development of ways through which we can increase their effectiveness, efficiency, and safety. Although many of the methodologies developed in the Human Factors domain map and investigate system properties and network structures, the inclusion of the temporal dimension in the analysis of STS remains limited. In this paper we present how modeling and visualization of STS can be augmented with the incorporation of temporal interaction analysis techniques that enable a micro-level, fine-grained analysis of data. We provide an overview of temporal analysis techniques by breaking down their main function, requirements, types of research questions they can address, and the visualization properties they offer, attempting to enhance their use in system analysis. This overview can assist researchers in selecting an analysis technique, enabling the incorporation of temporality in STS analysis, and helping towards the design of improved and safer systems and interventions.     

Pre–ndintermediate Oxidation Of Drinking Water With Ozone,Chlorine And “Chlorine Dioxide

With the application of chlorine gas in drinking water treatment processing after the turn of this Century, great success was achieved. With the advance of analytical techniques in the field of trace matter, Rook (1)as well as Bellar, Lichtenberg and Kroner (2) succeeded in 1974 to establish the presence of chloroform and other chlorinated compounds in treated drinking water, namely as the result of chlorination. During tests to minimize the problems of chloroform, of chlorite and chlorate by the simultaneous addition of chlorine andchlorine dioxide, it was discovered that already a small dosage of chlorine dioxide was sufficient to reduce drastically the formation of chloroform andother trihalomethanes. The aimof future treatment techniques in Zurich is the preoxidation with ozone in place of chlorine and chlorine dioxide. Considering the mode of effect of the various oxidizing agents and the longer flow time through the biological activated carbon filters (asa result of the ozonation), ozone is – according to studies made by Grob and the Zurich Water Supply with ozonized Lake Zurich water – the most economical oxidation process with the best effect, i.e., without formation of toxic or carcinogenic substances. The pre– and/or intermediate oxidation with ozone surely will be the right way in the foreseeable future.     

Destruction of Ozone Off–Gas by Thermal Catalytic Method

In the operation ofozone treatment plants, one will have to deal with ozone inthe off–gas exhaust air. In higher concentrations in the exhuast air, ozone has the unpleasant property of being detrimental to plant, animal and man.

The normal ozone concentration inambient air should not be more than 1/10of the MAK–value. Insmall treatment plants inEurope the small amount of ozone off–gas can be diluted with atmospheric airso that itis permitted to be discharged into the outside air. For larper plants there isthe choice between a thermal and catalytic ozone destruction, or a process that combines both. In the Lengg Waterworks the exhaust air of the reaction chamber was passed through a thermal destruction systen. From the granular activated carbon (GAC) filters theair was passed into the atmosphere untreated. It was ascertained that during GAC back–washing 1200 PPtl ozone were in the exhaust air. This ozone concentration was much too high.     

Single‐source dual‐layer amorphous IGZO thin‐film transistors for display and circuit applications

In this study, the authors report on high‐quality amorphous indium–gallium–zinc oxide thin‐film transistors (TFTs) based on a single‐source dual‐layer concept processed at temperatures down to 150°C. The dual‐layer concept allows the precise control of local charge carrier densities by varying the O₂/Ar gas ratio during sputtering for the bottom and top layers. Therefore, extensive annealing steps after the deposition can be avoided. In addition, the dual‐layer concept is more robust against variation of the oxygen flow in the deposition chamber. The charge carrier density in the TFT channel is namely adjusted by varying the thickness of the two layers whereby the oxygen concentration during deposition is switched only between no oxygen for the bottom layer and very high concentration for the top layer. The dual‐layer TFTs are more stable under bias conditions in comparison with single‐layer TFTs processed at low temperatures. Finally, the applicability of this dual‐layer concept in logic circuitry such as 19‐stage ring oscillators and a TFT backplane on polyethylene naphthalate foil containing a quarter video graphics array active‐matrix organic light‐emitting diode display demonstrator is proven.     

Peeling Meshed Potatoes

We study variants of the potato peeling problem on meshed (triangulated) polygons. Given a polygon with holes, and a triangular mesh that covers its interior (possibly using additional vertices), we want to find a largest-area connected set of triangles of the mesh that is convex, or has some other shape-related property. In particular, we consider (i) convexity, (ii) monotonicity, (iii) bounded backturn, and (iv) bounded total turning angle. The first three problems are solved in polynomial time, whereas the fourth problem is shown to be NP-hard.     

Silver Zeolite Composites‐Based LEDs: A Novel Solid‐State Lighting Approach

Silver clusters incorporated in a zeolite matrix represent a promising alternative for rare earth phosphors, organic dyes, and quantum dots as emitters in organic and hybrid organic/inorganic light‐emitting diodes (OLEDs). Compared to other existing types of emitters, they combine an excellent stability to oxygen and humidity with a high luminescence quantum yield and color tunability. This study reports on the first use of these silver exchanged zeolites embedded in polyvinyl carbazole (PVK), which is expected to act as a conducting matrix, as emitters in a single‐layer OLED. It is demonstrated that the introduction of these Ag zeolites leads to electroluminescence bands that clearly differ from pristine PVK OLEDs as well as from the photoluminescence spectra of the Ag zeolites. The current density and the spectral properties observed in these devices are strongly influenced by the zeolite silver loading, paving the way for a new type of easily tunable hybrid and cost‐effective OLEDs.     

Myth against history: the Concert Hall in Bruges by Robbrecht and Daem Architects

The Concert Hall in Bruges by Robbrecht and Daem Architects was built as the result of a closed competition held in 1998. The competition and its outcome generated a lively public debate that not only indicated how closely views on the city's identity were bound up with appreciations of its architecture (both from the present and the past), but also to what extent architecture embodied the problematic presence of the past in the contemporary city of Bruges. Robbrecht and Daem developed their project from themes proper to their oeuvre rather than to this specific debate. This approach not only allowed the firm to formulate a thoughtful response to the site of the Concert Hall. It also established the Concert Hall as a building that bypasses the conflation of architecture and identity, or the seemingly inevitable question of architecture's authenticity in an historical and historicised environment, to create a place that offers an opportunity to experience fully and to examine the city in the present.     

Scale,mergers and efficiency: the case of Dutch housing corporations

The efficiency of social housing providers is a contentious issue. In the Netherlands, there is a widespread belief that housing corporations have substantial potential for efficiency improvements. A related question is whether scale influences efficiency, since recent decades have shown a trend of mergers among corporations. This paper offers a framework to assess the effects of scale and mergers on the efficiency of Dutch housing corporations by using both a data envelopment analysis and a stochastic frontier analysis, using panel data for 2001–2012. The results indicate that most housing corporations operate under diseconomies of scale, implying that merging would be undesirable in most cases. However, merging may have beneficial effects on pure technical efficiency as it forces organizations to reconsider existing practices. A data envelopment analysis indeed confirms this hypothesis, but these results cannot be replicated by a stochastic frontier analysis, meaning that the evidence for this effect is not robust.