‘The Reconstruction of the Past is the Task of Historians and not Agents’

State security archives in Eastern Europe are shedding new light on the operative practices of the secret services and their interaction with performance art. Surveillance, tracking, undermining, disruption, writing of reports, and measure plans were different operative methods to be carried out in continuous repetitive processes. This paper argues that, through these repetitive working processes, state security agencies were permanently engaged in different forms of reenactments: of orders, legends, report writing, and inventing measure plans. With this operative reenactment, state security agencies not only tried to track down facts but also created ‘fake facts’ serving their agenda. These `fake-facts` were then again repeated and reenacted by informants endlessly to be `effective` in the surveillance and elimination of performance art.

New relaxed stability and stabilization conditions for both discrete and differential linear repetitive processes

The paper develops new results on stability analysis and stabilization of linear repetitive processes. Repetitive processes are a distinct subclass of two-dimensional (2D) systems, whose origins are in the modeling for control of mining and metal rolling operations. The reported systems theory for them has been applied in other areas such iterative learning control, where, uniquely among 2D systems based designs, experimental validation results have been reported. This paper uses a version of the Kalman–Yakubovich–Popov Lemma to develop new less conservative conditions for stability in terms of linear matrix inequalities, with an extension to control law design. Differential and discrete dynamics are analysed in an unified manner, and supporting numerical examples are given.

Time and Technology: The Temporalities of Care

By focusing the temporalities of care, the chapter analyzes a special relation between time and technology that underlies the making and persisting of media and infrastructures. I propose to differentiate between four types of care practices with corresponding different temporal patterns that are highly relevant for the functioning of technological systems in the past and present. First, the retrospective response to unforeseen interruptions (repair); second, the prospective routine procedure to prevent all forms of disorder (maintenance); third, a neglect of care that leads to devaluating infrastructure (abandonment) as well as—fourth—forms of revaluation in changing contexts (repurposing). Taking the new Berlin airport BER as an example, it will be shown that infrastructures exhibit different layers of temporality formed by these cyclic and repetitive processes of care and their transforming effects. Thus, even the performance of the most “hardwired,” late modern technology systems is crisscrossed by temporal regimes that stem from older, non-modern temporalities of care.

Iteration vs. Recursion

Iteration and recursion are two essential approaches in Algorithm Design and Computer Programming. Both iteration and recursion are needed for repetitive processes in computing. An iterative structure is a loop in which a collection of instructions and statements will be repeated. A recursive structure is formed by a procedure that calls itself to make a complete performance, which is an alternate way to repeat the process.

SCHEDULING OF REPETITIVE CONSTRUCTION PROCESSES WITH CONCURRENT WORK OF SIMILARLY SPECIALIZED CREWS

The highest degree of construction works harmonization can be achieved when planning a repetitive project with processes replicated many times in work zones of identical size. In practice, structural considerations affect the way of dividing the object under construction into zones differing in terms of scope and quantity of works. Due to this fact, individual processes are being allotted to different non-identical zones. Most methods intended for scheduling repetitive processes were developed with the assumption that the work zones are identical and that a particular process cannot be concurrently conducted. To address this gap, the authors put forward a mathematical model of the problem of scheduling of repetitive processes that are repeated in different work zones with the following assumption: several crews of the same type are available, thus particular process can run simultaneously in different locations. The aim of optimization is minimizing the idle time of all crews under the constraint of not exceeding the contractual project duration. The proposed mixed binary linear programming model can be solved using software available in the market or developed into a dedicated system to support decisions. To illustrate the benefits of the model, an example of scheduling interior finishing works was provided.