Papers by Keyword: Instrumentation

Abstract: Ambient vibration instrumentation is a non-destructive in-situ testing method that can be used to assess the dynamic properties of a building. By analyzing the time histories of accelerations, velocities and displacements (both instantaneous maximum values, or averaged RMS values) and applying specific evaluation criteria, we can estimate the extent of any potential damage. In 2016 and 2021, the ISIM Timisoara building underwent in-situ testing through ambient vibration measurement, using different sensor placement schemes (horizontal, vertical with an external sensor, and sensor at the last level), to accurately characterize the complex structural system. Furthermore, an analysis of the interaction between the structure and the soil is also provided. The approach outlined in the article assists in evaluating the national-level vulnerability of the built environment.

Abstract: A method for continuous measurement of particle and particle precursor material in high purity liquids using aerosolization and condensation particle courting (A+CPC) is presented. A process for correlating wafter defects with the concentration values measured using A+CPC using Sequential Spin Coating + Surface Enhanced Particle Sizing (SSC + SEPS) is described. The method was applied to monitor the rinsate of an ion exchange resin following the SEMI C93 guide. The results showed correlation between the methods and the concentration values were used to calculate a deposition factor (liquid concentration/surface concentration) on the order of 1E5 (#/ml)/(#/cm²).

Abstract: A set of scale-model tests carried out to enlarge the range of wave steepness values analysed in run-up, overtopping and armour layer stability studies, focusing on oblique extreme wave conditions and on their effects on a gentler slope breakwater’s trunk armour and roundhead, is presented in this paper. A stretch of a rubble mound breakwater (head and part of the adjoining trunk, with a slope of 1(V):2(H)) was built in a wave basin at the Leibniz University Hannover to assess, under extreme wave conditions (wave steepness of 0.055) with different incident wave angles (from 40º to 90º), the structure behaviour in what concerns wave run-up, wave overtopping and damage progression of the armour layer. Two types of armour elements (rock and Antifer cubes) were tested. Non-intrusive methodologies including a new application of laser scanning technique for the assessment of both armour layer damage and wave run-up and overtopping were used. It is expected that such work will contribute also with data to improve empirical formulas as well as to validate complex numerical model for wave-structure interaction.

Abstract: In this work, we proposed and demonstrated an efficient optoelectronic system capable to detect 1 gram of salt per liter of water (0.1% salinity) in real time employing optical fiber technology as sensing medium and embedded systems of National Instruments Company to get an accurate instrumentation process. In addition, the sensitivity of this salinity sensor can be enhanced by reducing the diameter of the optical fiber sensor structure ( by employing a controlled tapering process. More specifically, the sensitivity of this device has been raised from 141.933 nm/Refractive Index Unit (RIU) for an un-tapered sensor structure to 352.915 nm/RIU for a tapered sensor structure . In fact, considering that the tapered sensor structure provides an approximately linear response with a maximum sensitivity of 0.6624 nm / % salt, the percentage of salt is easily identified by monitoring the peak wavelength response.

Abstract: This paper presents the results of two load tests carried out in a continuous flight auger pile of 0.4 m in diameter and 12 m in length. The pile was instrumented in depth with strain gages in order to obtain the load capacity along the shaft and the tip. The load tests were carried out at the University of Campinas Experimental Site Test. The subsoil where the pile was installed is constituted by a first stratum of Silty Clay, which is porous and collapsible, of 6.5 m in thickness, followed by a stratum of residual soil of Clayey Silt up to 14 m depth. The first load test was the slow type, and a quick load test in the same pile after five days. From the results obtained with the use of instrumentation, the values for both lateral and tip load were determined in each one of test carried out in the pile studied. With these results and applying the Cambefort’s Law, it was could evaluate the evolution of the shaft friction and tip load in relation to the associated settlements, as well as the occurrence of residual load. The ultimate load obtained in the test was 960 kN and 810 kN for the first and second tests, respectively. The stress for the tip was 853 kPa and 655 kPa for the first and second tests, respectively.

Abstract: Runtime verification checks whether one system execution conforms to a group of specific requirements. One of the many problems concerned is how to lower the costly instrumentation overhead, because the performance is as important as correctness. The solutions to cope with the problem include static checking, and hardware based instrumentation. What makes a difference to our approach is that it takes into account the modular structure of the observed run, and our approach makes a tradeoff between observability and cost by means of simulated annealing algorithm. The paper gives a definition of instrumentation observability in detail. The simulated annealing approach works out an optimized instructive instrumentation solution containing part of all the observing points. An experiment is conducted on the LwIP protocol stack to prove the effect of our observing strategy.

Abstract: Path coverage testing is almost impossible to achieve because of the large number of paths. The function calling path coverage analysis method can guaranty adequate test coverage rate effectively on the precondition of unit testing completion. Based on function calling relations, the methods of dynamic generation function calling path is proposed. For cycle and recursive calling, design instrumentation rules and probe function, complete source code instrumentation, ensure the stub point flow can trace to the function calling relations. The function calling path generation algorithms were designed to split the stub point flow to the dynamic function calling path. Experimental results show that the dynamic function calling path generation method based instrumentation can extract the function calling paths which are executed by test cases and gain the coverage of information automatically.

Abstract: The control engineering technology is a huge field of study. Above all, the instrumentation and control, likewise the plant automation has been classified as a special field of this technology. In this thesis we are introducing a practical learning material system that deals with instrumentation and plant control theory using LEGO Mindstorms and LEGO Bricks. There are different parts in the plant such as field instruments, controllers and analyzers, which are linked together to maintain a stable level of production. We are assuming that colleges and new employer will be able to use the developed system.

Abstract: The greenhouse effect is a naturally occurring process that heats the Earth's surface and atmosphere. It is a result of the fact that certain atmospheric gases, such as carbon dioxide, water vapor, and methane, are able to change the energy balance of the planet by absorbing long wave radiation emitted from the Earth's surface. Number of gases are involved in the human caused enhancement of the greenhouse effect. Carbon dioxide is the most important gas of these gases, which contributes about 55% of the change in the intensity of the Earth's greenhouse effect. The global monitoring of the greenhouse gases is necessary for handling the global warming issue. This paper presents a practical implementation of a measurement station for environmental monitoring using Internet technology and large sensor networks. The application of the sensor networks in the environmental monitoring requires the development specific solutions. This paper presents a solution that relies on existing technology, but offers hardware and software upgrade due to the advantages of using the concept of virtual instrumentation. The application uses temperature sensors, air relative humidity sensors, gas sensors and others. The measurement station collects the data from the sensors and sends them to the users using the UDP protocol via the Internet and GPRS modem. The measurement station was implemented in LabVIEW programming package.

Abstract: This study presents the establishment and instrumentation of a laboratory for investigating how different soils behave under controlled conditions in cold climates. Ground conditions are extremely important in regards to the building sector. Establishing new infrastructure and buildings require high competence about the ground/soils in order to build robust and long lasting foundations and constructions. In cold climates, soils are frequently exposed to freezing and thawing cycles, and building projects often require additional resources compared to similar projects further south. During 2009-2010, a new laboratory was established in Narvik, Norway. The laboratory consists of 4 different 6x6m bins containing different homogenous soils down to a depth of 3m. A special designed measurement frame has been placed inside each bin, which facilitates instrumentation for thermal and hygroscopic measurements. The laboratory has many applications which may lead to advances within knowledge about thermal response of soils, artificial thawing for more efficient building in cold climates, faster dehydration and curing of concrete during winter, improved road foundations and preventing frost heaves and so on. This study describes the laboratory setup and presents test measurements on thermal responses of sand, silty sand and gravel during artificial thawing using a hydronic thawing system.