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Design and implementation of a programmable middleware

Design and implementation of a programmable middleware

Microsoft . NET . Microsoft . NET is a successor to COM built on a common runtime for so-called managed code. The runtime has control over all as- pects of execution, including, in particular, loading and linking of compo- nents (called assemblies). Assemblies can be addressed by their file name relative to the application’s installation location, which means that a com- ponentized application can be installed by just copying a directory tree (termed XCOPY deployment, alluding to a DOS recursive file copy command). Assemblies can be addressed by any number of the following constituents: name, locale, processor architecture, and version number. Also, assemblies can be signed by a cryptographic key (called a strong name); in this case, the linker will fail unless it finds the exact same assembly at run time. Assem- blies can be installed into the global assembly cache, or they can be located using a search path. Every application domain (similar to component man- agers, but with strong isolation guarantees) can have its own search path. Application programmers can define custom loaders, but do not have full control: the default assembly loader is always tried first; only if it fails will the user have a chance of delegating to his own loading behavior.
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Design, implementation and characterization of synthetic riboswitches in Saccharomyces cerevisiae

Design, implementation and characterization of synthetic riboswitches in Saccharomyces cerevisiae

81 which populations are regarded as different. Although being rather similar to the ROC analysis, ROC analysis is independent of a threshold to summarize the performance of a given logic gate. Moreover, if transient fold-changes are recorded, the ROC analysis can be used to compute the speed with which the gate reaches its maximum accuracy. A particular gate design can subsequently be mapped into a whole design space determined by accuracy and speed allowing direct comparisons to other designs and their performance to elucidate the best possible design for a given operation (Fig. 6B, C). These analyses are beyond what is feasible with the approach of probability binning. Collins and co-workers did not consider phenotypic noise at all to calculate switching factors and did so solely by extraction of the mean fluorescence from the corresponding histograms. Besides, the discussed studies used steady state measurements that only allowed to assess the equilibrium of all involved rate constants, and hence all transient information needed to dissect transitions from one Boolean state into another was lost. In the present study the model built and calibrated on the transient single-cell data was not only employed to perform ROC analysis, but also to determine the gate’s full dose response profile at steady state. In such a way, the device’s output over the time course of simulated prolonged exponential growth was emulated; data that were beyond the experimentally feasible time window as these growth phase may only be maintained up to about 8 h in synthetic complement medium supplemented with all necessary nutrients. To solve this issue of limited exponential growth an alternative approach, the EnPresso ® growth systems, had been developed by BioSilta. Generally applied to extend exponential
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Design, Implementation and Evaluation of an Anti-Phishing Education App

Design, Implementation and Evaluation of an Anti-Phishing Education App

There are several proposals in literature for embedded learning [46, 47, 51]. One of these is a solution proposed by Jansson et al. [46] where simulated phishing e-mails with links to fake websites or malicious download attachments are sent out to users. The moment a user falls for a trap of these simulated e-mails he receives a notification informing him that he could have fallen for a real phishing attempt. Also, the e-mail includes a link to a website with a training program with general information and tips on how to detect phishing and malicious attachments. After consulting the training program the user is asked to complete a questionnaire in order to verify whether he understood the content of the training program. A very similar approach, the so called PhishGuru [47], is proposed by Kumaraguru. Another possibility is to leave out the step where simulated phishing e-mails are sent to users. Instead actual phishing e-mails are utilized. For example, the APWG and Carnegie University’s CyLab Usable Privacy and Security Laboratory (CUPS) work on the project “Phishing Education Landing Page” [52]. The moment a user clicks on a link of a real phishing website which has already been taken down, i.e. the moment the user behaves riskily, he is redirected to the anti-phishing landing page. There he is told that he had almost become a victim of phishing and provided with educational material to this topic. Finally, there is an approach where the intervention does not happen after clicking on a dangerous link, but while surfing [51]. When the user lands on a blacklisted phishing website and is about to disclose his sensitive data, i.e. presses the submit button, the system interferes: the user is warned and given tips on how to detect phishing websites (for example, he is provided with abstract information on the detection of spoofed URLs). As discussed before, all of these solutions benefit from the so called teachable moment (cf. Section 2.4.2). A downside of these
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Holistic design and implementation of pressure-actuated cellular structures

Holistic design and implementation of pressure-actuated cellular structures

Automotive applications like spoilers, sunroofs, cladding parts or doors provide advantages regarding actuation efficiency, part reduction and design. Using an already available on-board pressure supply, PACS can provide a lightweight alternative to conventional rigid components. General applications like seats, investigated by Pagitz et al. [18], adaptive hospital beds, shape- variable airfoils for wind power plants and gripping devices can be implemented by utilizing the concept of PACS. Sun shields or photovoltaic systems could be aligned optimally with the sun by PACS, which uses solar radiation to heat and expand fluids within its cells. Aerostatic effects are used for pressurizing PAHs and are investigated by Barrett et al. [12]. Hydrostatic forces in a similar way allow realizing stabilizers for ships. PACS are conceived to be utilized in an aeronautical application. Rigid aircraft structures restrict available systems in, agility [19], efficiency, operating range [20], [21] and load control [22]. Emission, aerodynamic and functional advantages can be reached by substituting flaps, high-lift systems and spoilers by shape-variable counterparts. A particular promising target structure, the variable-camber wing, is investigated in the following. PACS in this context offer the opportunity to substitute heavy conventional control surfaces, while optimizing the aerodynamic efficiency for multiple flight conditions.
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Design and implementation of a data storage abstraction layer for the Internet of Things

Design and implementation of a data storage abstraction layer for the Internet of Things

The reproducibility of the performance evaluation presented in this chapter is se- verely limited by a number of factors. To achieve high reproducibility, the differ- ent systems would have to be tested on the same physical platform, running code generated by the same compiler and being benchmarked on the same workload. Unfortunately, none of these goals could be met. This is primarily because many of the previous developments in the area of WSN storage are comparatively old, and unfortunately unmaintained. To the author’s best knowledge, this applies to Match- box, ELF, TFFS and Capsule – all implemented for TinyOS 1.x – which has not been under development since 2005. But even if all these systems were under active development, a shared hardware platform which runs TinyOS, Contiki and RIOT would still be needed, but does not currently exist. In addition, the performance evaluation was carried out using a microSD card due to the lack of a platform with RIOT support that featured native flash memory. This is not optimal since, as ex- plained in Section 2.6, SD cards feature a dedicated microcontroller that performs many of the tasks carried out by the FTL (e.g., wear levelling). As a result, any measurements of throughput, latency, and energy consumption made using an SD card are worse compared to using raw flash memory when a separate FTL is al- ready implemented. In summary, the comparisons to other storage systems in this chapter must be understood under the premise that they are mere comparisons of benchmarks done on different systems, partially in different decades, and that the
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Design and Implementation of a Library for Recurring ETL Imports of Reference Data in Ruby

Design and Implementation of a Library for Recurring ETL Imports of Reference Data in Ruby

The underlying ideas for the library described in this thesis were taken from two projects developed at mindmatters GmbH & Ko KG which rely heavily on third party data, named Epic-Relations and Mercury. In both these projects the third party data was of such low quality that instead of maintaining the third party’s entity-relationship model within the respective projects, it was decided to implement an importer to transform the data into a simplified schema with a more maintainable and consistent entity-relationship model, better suiting the applications’ domains.
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Implementation of a circular product design – case study of a smartphone manufacturer

Implementation of a circular product design – case study of a smartphone manufacturer

The best-known approach is probably the one developed by Michael Braungart and William McDonough (2002). Their “Cradle to Cradle” framework attempts to turn ma- terials into nutrients by ensuring their perpetual flow within the biological or technical metabolism. In this scenario, biodegradable materials (biological nutrients) are ab- sorbed and, thus, have a positive effect on the environment (eco-effectiveness). Syn- thetic or mineral materials (technical nutrients) remain safely in the closed loop sys- tem between manufacture, reprocessing, and reuse in order to maintain their material value through the loops (Braungart et al. 2006). Any product design in such a scenar- io requires dealing with issues like biodegradability, disassembly, recyclability (or up- cyclability), reverse logistics, and material toxicity (McDonough & Braungart 2002). The authors emphasize minimization of energy consumption and materials use, min- imization of material diversity to promote disassembly and value retention as well as product processes and systems for further life cycles (ibid.).
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Design and implementation of a broadband RF-DAC transmitter for wireless communications

Design and implementation of a broadband RF-DAC transmitter for wireless communications

Moore’s law does not only lead to low production costs but also results in enormous signal and data processing capabilities of modern mobile phones. So- called smartphones have more computational power than most desktop computers in recent years. To allow an optimum user experience, smartphones have to support high-data-rate wireless connections. Furthermore, to be able to use a broad range of different services, these devices need to support a lot of different communication standards, such as UMTS, wireless LAN, Bluetooth, GPS etc. Also, older standards like GSM still have to be supported. Even several years after the rollout of a new broadband communication standard such as UMTS, good network coverage can only be expected in densely populated metropolitan areas, making GSM an indispensable fallback solution. Starting from 2010, the first 3GPP LTE (Long Term Evolution) networks are installed. LTE is the successor of the UMTS standard, enabling even higher data rates, up to 300 Mbps.
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A declarative model for web accessibility requirements – design and implementation

A declarative model for web accessibility requirements – design and implementation

A similar approach might be useful to evaluate dynamic web pages. Before testing the web page, a test plan consisting of the possible states of a web page and the possible transitions from each state is created. Ideally, this plan should be created automatically. In its current version, the web-a11y-auditor only tests single pages, but not complete sites. The state model approach described for testing dynamic pages might also be useful for testing sites. In this case, the states are the individual pages (identified by a unique URL) of the site. The links for changing to another page are the state transitions. Web pages that are part of a website often contain repeating components. One pos- sible approach for minimizing the work necessary for evaluating large websites is not to evaluate full pages but the components from which these pages are built. An open question is if the accessibility of components may depend on the context in which the components are used or if the accessibility of a component is independent of its context. It would be useful to integrate accessibility checks into the workflows of web developers to support them with the creation of accessible web pages and applications. One possible approach for the integration of accessibility checks into the workflow is the integration of accessibility checks into a continuous integration pipeline. One option for this integration could be a tight integration with Selenium. Selenium and other similar frameworks are already used by many projects for automatically testing the user interface. A possible integration of accessibility checks would provide a single method or function that can be called inside a test case. This function checks the accessibility of the current state of the evaluated page. If possible, this function should only check the changed regions of the evaluated page. The results are recorded. For tests that can not be done automatically, the test tool would add a note to the report indicating that a manual test is necessary.
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Design and implementation of a soft computing-based controller for a complex mechanical system

Design and implementation of a soft computing-based controller for a complex mechanical system

approach proposed show that the state variables estimation error approaches zero asymptotically. A neuro-sliding mode observer to state variables reconstruction of a quadcopter is proposed in [BB11]. The neuro-sliding observer has the same struc- ture as a simple sliding mode observer. The main goal is to reduce the observer sensitivity to noise. To realize the neuro-sliding mode observe two parallel feed- forward artificial neural networks are used, the first network estimates on-line the equivalent control term and the second generates observers feedback. The learning law for the network is based on Lyapunov stability theory. Simulation results show that the measurement noise is suppressed without any performance degradation. An Adaptive Neural Control (ANC) approach using a non-separation principle is proposed in [PSY15]. In this approach a hybrid estimation scheme integrating an adaptive NN observer with state variable filters is presented. The simulation results are done on a mass-spring-damper system. The results show that due to the low-gain feature peaking responses without control saturation can be avoided. Additionally, in comparison with the work published in [PPKM05] can be achieved. In [LF15] an adaptive backstepping control approach of Micro-Electro-Mechanical Systems (MEMS) of a gyroscope based on neural state observer is proposed. This control approach employs an RBFN-based observer to estimate the MEMS gyroscope states incorporated in the backstepping controller. The RBFN is used to estimate the nonlinear part of the gyroscope system model. The adaptation of the observer is investigated based on the Lyapunov stability framework in order to guarantee the accuracy of the observer. The simulation results demonstrate the accuracy and effectiveness of this approach.
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Design and implementation of a synthetic pre-miR switch for controlling miRNA biogenesis in mammals

Design and implementation of a synthetic pre-miR switch for controlling miRNA biogenesis in mammals

verschiedenen Kommunikationsmodule, abhängig von deren Länge und Volumen, und der Ersatz der natürlichen terminalen Schleife die Prozessierung in unterschiedlichem Maß beeinflussten. Letztendlich stellte sich heraus, dass die Verknüpfung über ein G-C Basenpaar die beste Möglichkeit bot, um die Prozessierung aufrecht zu erhalten und ein effektives Schaltverhalten herbeizuführen. Basierend auf dieser Erkenntnis konnte das Design erfolgreich auf weitere miRNA Vorläufer (miRNA- 34a und -199a) übertragen werden, die sich hinsichtlich ihrer Struktur von der miR-126 unterschieden. Auch hier konnte eine effektive Schaltaktivität von bis zu 400-fach nachgewiesen werden. Die Inhibition der Prozessierung des miRNA Vorläufers konnte durch die Zugabe von Doxyzyklin auch hier vollständig aufgehoben werden. Die entwickelten RNA-Schalter wurden daraufhin mit Hilfe eines Reportergen-Assays auf ihre Aktivität bezüglich der Regulation von miRNA Zielgenen überprüft. Hierzu wurden natürliche miRNA-Zielsequenzen hinter ein Reportergen eingebracht und die Bindung der miRNAs in Abhängigkeit von der Aktivität der Schaltelemente getestet. Es konnte gezeigt werden, dass der Großteil der Schaltelemente zur Regulation der Reportergenexpression geeignet war. Um Informationen über die Kinetik des Schalters miR-199a_2 zu gewinnen, wurden zeitaufgelöste Messungen zur Bestimmung der Ansprechverhaltens des Schalters auf die Zugabe von Doxyzyklin durchgeführt. Es konnte gezeigt werden, dass bis zu 30% der Prozessierungsaktivität bereits 1 h nach Doxycyklinzugabe wiederhergestellt und innerhalb von 24 h vollständig wiedergewonnen werden konnte. Im Anschluss wurde das regulatorische Potential der Schalter bezüglich endogener miRNA Ziele betrachtet. Dazu wurde die für den Schalter miR-199a_2 kodierende Sequenz entweder transient in die Zelle eingebracht oder in das Genom der Zelle integriert. Durch die genomische Integration wurde eine geringere Expression der Schalter-basierten miRNA beobachtet, was mit einer Verringerung des Schaltfaktors einherging. Eine Regulation der endogenen Ziel-mRNAs SMAD4,
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Middleware and Application Management Architecture

Middleware and Application Management Architecture

The first layer focuses on the presentation of information along with the verification of results to support the specification and the submission of individual tasks. The specification answers six questions about a task: Who? (identifier) wants What? (request) Where? (destination) When? (schedule) Why? (purpose) and How? (execution plan). The answers to Who?, What?, When?, and Why? are the basis for a submis- sion that is a complete job specification. The re-specification is responsible for the mapping of What? towards a set of commands that is needed to be executed to fulfill the purpose. Triggering activates and deactivates jobs based on date and time information, completion of other jobs, or other available data. Queuing provides load balancing and the prioritizing of jobs. Access functions as a mediator between the above layers and the execution layer. It provides interfaces to resources. Execution executes any job that is submitted from submission via access. The type of service executed here depends on the overall pur- pose of the system and might range from database access, media conversion, user interaction, up to device and network usage. All described layers are supported by navigation, security, metering, and logging. These commonalities between information mapping and system management should lead to a similar design of software that handles them. However, the reality is different. Management activities are out- sourced to specialized systems that act independent of the systems they manage. The reason for that is the evolution of network systems. Starting with basic services (telephony and data transmission), the first two types of networks that existed had had no need for automated management. The networks had been oper- ated manually. Changes in society and on the market have led to the extinction of this business model. Networks have become connected, the market has demanded more than the basic services, and the num- ber of devices has increased. This resulted in the actual need for an automated management of services and resources to continue to run the network in an efficient (and profitable) way. The operation of ser- vices and their management became separated areas with different approaches. Today, distributed sys- tems and services run on top of middleware and are managed by dedicated management systems.
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Design and implementation of a generic modeling framework - a platform for integrated land use modeling

Design and implementation of a generic modeling framework - a platform for integrated land use modeling

Land-use as “the total of arrangement, activities and inputs that people undertake in a certain land cover type”, in contrast to land-cover being the “observed physical and biological cover of the earth’s land, as vegetation or man-made features” (FAO, 1999), is a crucial link between human activities and the natural environment and one of the main driving forces of global environmental change (Lambin et al., 2000). Large parts of the terrestrial land surface are used for agriculture, forestry, settlements and infrastructure. Concerns about land-use and land-cover change first emerged on the agenda of global environmental change research several decades ago when the research community became aware that land-surface processes influence climate (Lambin et al., 2006). While the focus in the beginning lay on the surface-atmosphere energy exchanges determined by modified surface albedo (Ottermann, 1974; Charney and Stone, 1975; Sagan et al., 1979), the view later on shifted to terrestrial ecosystems acting as sources and sinks of carbon (Woodwell et al., 1983; Houghton et al., 1985). A broader range of impacts of land-use change on ecosystems was identified since then. Besides being a major influencing factor on climate (Brovkin et al., 1999), land-use meanwhile is regarded the most important factor influencing both biodiversity and biogeochemical cycles on the global scale (Sala et al., 2000). To close the circle, land-use itself is strongly influenced by environmental conditions like climate and soil quality, affecting e.g. suitability for certain crop types and thus affecting agricultural use or biomass production (Mendelsohn and Dinar, 1999; Wolf et al., 2003).
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The Design, Simulation and Implementation of Inductively Powered Sensor Systems: New Applications, Design Methodologies and a Unique Coil Topology

The Design, Simulation and Implementation of Inductively Powered Sensor Systems: New Applications, Design Methodologies and a Unique Coil Topology

Wireless technologies have connected people to information and others at constantly and throughout the world. We are in the middle of a wireless revolution, where bil- lions now rely these services for both business and pleasure. The wireless revolution started in the 1940’s when military and civilian personnel began using wireless ra- dios. In the 1960’s, mobile car phones began to be installed in vehicles, but at a weight of 40 kg for the Mobile Telephone B (MTB), the devices were impractical for truly mobile purposes. In 1973 an electrical engineer working for Motorola, Martin Cooper, developed the first portable cell phone which weighed over 1 kg, had a talk time of just 30 min and took 10 h to recharge. As national cellular networks began emerging in the 1980’s, cell phones began proliferate throughout business and then throughout the general population in the 1990’s. Today’s cell phones are a fraction of the size and cost and have become, both in developing and developed nations, the standard communication device. These devices have benefited greatly from Moore’s Law, becoming smaller, cheaper and thus having longer battery life. In fact, a bat- tery life of 10 days or more is not uncommon. In the 1990’s, since the dawning of the personal computer, computing has become more and more mobile. A large num- ber of mobile devices that merge computation with communication have emerged in such things as smart phones, net-books, tablets, etc. In the industrial world, many devices now share data over a wireless connection. Today, it is easier than ever to outfit any device with short, medium or long range wireless communications for process automation, data acquisition, etc. In fact, for reasons of flexibility and cost, wireless devices are preferred or even required since such devices save on wiring costs and offer a high degree of flexibility.
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Automation of Design-Tasks for Programmable Microuidic Devices / submitted by Berislav Klepic, BSc

Automation of Design-Tasks for Programmable Microuidic Devices / submitted by Berislav Klepic, BSc

All of these tasks result in a huge amount of solutions, there are many variables that need to be set. Every sample, pump and route need to be computed over the given PMD-grid. This has to be done for every time-step. The overall task results in a computational hard problem. To get the best solutions, the full search space for this big amount of solutions needs to be explored. Instead of implementing a new heuristic, which would take a lot of time due to the big search space, the idea is to use formal methods. These already have intelligent decision heuristics, which can efficiently deal with a large search space. It has been proved that these methods are very efficient in certain other areas like automated test pattern generation and formal verification ([22]), as already explained in Section 2.3. The idea is to use a solver for Boolean satisfiability (SAT), because as [15] shows it is possible to utilize this method to combine all constraints that are needed and find a solution for the three tasks. How this solver works is described in Section 2.3.
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Concept, design and initial implementation of the de.NBI Cloud Portal

Concept, design and initial implementation of the de.NBI Cloud Portal

Amazon is alongside Google, Microsoft, and IBM one of the world’s leading cloud providers. One outstanding product is the Amazon Web Services Elastic Compute Cloud (AWS EC2). The configuration of custom instance types is not possible in EC2 but there are approx. 80 different instance types 1 available that define different virtual machine (VM) configurations, in particular, the number of cores, size of RAM, storage, and network bandwidth. Each instance type has its on-demand bundle price which varies from the region (15 regions available 2 ). The user is charged hourly depending on the used resources. Additionally, to the on-demand prices there is an option to reserve the instances for the long term and to pay for the resources upfront. The prices for reserved instances are lower than on-demand and vary depending on the reservation time: longer reservations result in lower prices. Besides the on-demand and reserved instances AWS offers a cheaper on-demand alternative called “spot instance”. Spot instances use the reserve capacity of EC2 and get immediately shut down when they are needed elsewhere. Therefore, spot instances are only available for specific instance types and are suitable for applications with flexible start and end times.
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The job guarantee: Design, jobs, and implementation

The job guarantee: Design, jobs, and implementation

Of course it is. We guarantee access to a public library to everyone. There may be some circumstances when a person is asked to leave the premises, but unless they threaten the public’s safety, they are not denied access to the public library the next time they show up. Another example is public education, which is guaranteed to all children. Sometimes students get into trouble and are suspended or expelled. As a matter of principle (though it can surely be improved upon in practice), we seek ways to help these students—we make referrals and find rehabilitation programs, or connect them with community liaisons and at-risk youth programs to help them stay in school and be successful. Again, while some kids fall through the cracks and much more is needed to help them, this is the principle that underpins public education—that it is guaranteed to all, and that everyone has the right to education.
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Structured Parallelism by Composition - Design and implementation of a framework supporting skeleton compositionality

Structured Parallelism by Composition - Design and implementation of a framework supporting skeleton compositionality

The binary tree or tournament scheme is a common pattern in parallel programming to calculate reductions or to gather data in ⌈log 2 p⌉ parallel steps for p processes. The communication pattern is simple to express using a binary-representation of the processes indexes. In step i, those processes communicate which differ only in bit i and which do not have any bit set at all positions smaller than i. The process with a bigger index sends its message to the process with the smaller index. An example using 16 processes is depicted in Figure 4.11a. We define a functional version of this pattern as Eden skeleton using remote data. We do not use any bit arithmetic, instead we use a transformational way to determine the communication partners. An observation of the example in Figure 4.11a reveals that in the first step, every odd process sends data (depicted red) and every even process receives data (depicted blue). After sending data, processes get inactive (white). In the subsequent steps again, every second active process sends data (red) and the other active processes receive data (blue). In our implementation, we move remote data in a list from the position of the sending processes to the position of the receiving processes. The topology is defined in function partnering of Figure 4.11b. The input list of type a ,
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Design and Implementation of a New Local Control System at the S-DALINAC

Design and Implementation of a New Local Control System at the S-DALINAC

old application. It leads to the discussion of the limitations of the system as it was present at the beginning of this thesis. Very detailed description of the hard- and software can be found in the doctoral theses [3, 4] and the references therein. The former system was based on a PDP11 computer system operating under RSX-11M-Plus. It was nearly impossible to employ an existing accelerator control system of another accelerator site because those systems rely on standard hardware. Since many components of the S- DALINAC were build by the electronics workshop of the institute the amount of work to adapt another system would have been of the same volume as programming an individual S-DALINAC control system. The operating system RSX was selected because an expertise and experience was already gained while building up a data acquisition system [13]. Local control software. The former control system’s architecture follows rudimentarily the layout of an operating system. All components are implemented on a single PDP11. Figure 2.3 illustrates the abstract view of the former local control system software. Core of the application was the central STEUER task and the common block STCOM. Later improvements and enhancements were provided by the Ethernet communication providing the ETHSTE task and various user programs. The STCOM stored all information about the device controllers (DCBs) and attached units (UCBs) in the global memory providing a device database. The content and size of this database had to be defined at compile-time and was fixed throughout program execution. There was no protection
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Design and implementation of a verifier for sequential programs using the Hoare calculus

Design and implementation of a verifier for sequential programs using the Hoare calculus

The Hoare calculus is good in theory but very difficult to apply and reenact since there are a lot of cavities and eventualities to account for. There is no single straightforward way to make use of it and the verification process must often be supported by the user. This is why a program should be annotated with assertions and loop invariants. The arising question is whether those annotations are chosen correctly then in order to meet the expectations of the developer. Program verification is a bit of a self- fulfilling prophecy, the software engineer inserts more information with the ambition of constraining malfunctioning scenarios, trusting that additional information (hopefully this is done by peers). The axioms and rules are general enough that the implementation and strategies are heavily dependent on the language. The semantics of the elements in assertions, the types of predicates and symbols, whose correctness must be ascertained, are the pivot point for what statements may be constructed. The topic is copious, can be scrutinized further for sure and concedes space for creativity. Finding loop invariants is usually regarded as an intuitive task. Maybe such vagueness could be combined with machine learning or databases be gradually fed with previously regarded proof outlines. Implication checks for the observed arithmetics are feasible but may fail in detail. Similarly to solving equations in school, sometimes it requires a sharp eye or the right application of conversion rules to get the proper result. The expansion of expressions appears to be very arbitrary, trial and error, but instead of only reducing them to a final format, which is ambiguous and more so with an enlarged language, intermediate comparisons and reshuffling multiple reduced representations should be able to solve more implication problems.
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