The dome with ribs and rings, which covers the ROMEXPO pavilion from Bucharest, was designed afte... more The dome with ribs and rings, which covers the ROMEXPO pavilion from Bucharest, was designed after the collapse of the single layer reticulated dome. In this paper, it was made the checking of the structure, under the dynamic loads with three recorded accelerograms calibrated according to Romanian seismic design code P100-1/2006. Under the action the dynamic loadings, it was made a time-history analysis to determine the zones where the plastic hinges appear, at what accelerations and their position on the structure. The studied dome is formed by 32 spatial semi arches and three rings: one circular ring located at the top of the dome and another two rings, design as trusses, the first near the supports and the second as an intermediate rings above the skylights. Above the skylights up to the top, the dome is tight together with purlins and bracings.
An important part of the reform of the intelligence community is felt in the opening linked with ... more An important part of the reform of the intelligence community is felt in the opening linked with the widening spectrum of methods and spaces which can be used to collect and analyse dates and information. One of these methods that produce large mutations in the system is connected to the world of social media which proves to be a huge source of information. Social Media Intelligence (SOCMINT), the newest member of the family INT's, is undoubtedly a separate domain, a practice rooted in the work of the intelligence community. This paper proposes a general characterization of the most important aspects of Social Media Intelligence, a brand new way for the intelligence community to collect and analyse information for national security purposes (but not only) in the context of the current global challenges. Moreover, the work is focused in identifying the further limitations and opportunities of this practice in the upcoming decade.
The voting behaviour of migrants has been studied extensively but limited attention has been paid... more The voting behaviour of migrants has been studied extensively but limited attention has been paid to how the discussion with families in the home country can be important. This article analyzes under what circumstances migrants influence or are influenced by their families in voting decisions. The analysis uses individual-level data from a survey conducted in 2018 on a sample of 1,839 Romanian migrants. The results indicate that most migrants are not engaged in acts of persuasion about voting. Those who influence their families have a direct interest in the election results, are informed about what happens in the country and are politically active. The migrants who are influenced by their families have limited experience in the countries of residence and strong ties to their home country.
The paper presents the results and the similarity between the experimental test and FEA of a stee... more The paper presents the results and the similarity between the experimental test and FEA of a steel frame connection. The same connection is analyzed in two situations. The second case analyses the connection having some of the elements strengthened in order to increase the capacity of the specimen. The analysis is performed using solid finite element and is compared to the experimental test performed in the laboratory. Several considerations, such as identical conditions for force definition, have to be taken into account in order to obtain good results. Key-Words: deformed shape, strengthen, strain gauge, boundary conditions, stresses.
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016
In PET detector designs, high sensitivity is a critical performance parameter required for obtain... more In PET detector designs, high sensitivity is a critical performance parameter required for obtaining images with reasonable signal-to-noise ratio (SNR). The sensitivity of a PET scanner is primarily determined by the efficiency of detection system (e.g. crystal thickness and solid angle coverage), but could be enhanced by distinguishing and recovering inter-crystal Compton scattering events while maintaining good timing resolution. Generally, identification of such events is based on the measured energies deposited in each crystal; however, the energy performance of SiPM device is affected by the inherent non-linearity of the SiPM response. The measured electric signal exhibits a nonlinear relationship to the number of detected incident photons due to saturation, optical crosstalk, and after pulse. To investigate the sensitivity improvement and timing resolution of inter-crystal Compton scattering events and correct for the presence of saturated SiPM and thus non-linearity in energy...
We describe new high-resolution depth-of-interaction (DOI) PET detector designs based on avalanch... more We describe new high-resolution depth-of-interaction (DOI) PET detector designs based on avalanche photodiodes (APDs). With the development of APDs which utilize thin drift regions to speed response time, these detectors promise improved timing performance relative to previously reported APD-based DOI detectors. The new designs also offer improved decoding of smaller crystals at room temperature through the use of a combination of position-sensitive APDs and pixellated APDs. The number of read-out channels for these designs is kept much smaller than the number of scintillator crystals by ganging together APD outputs in an encoding pattern which still allows for the correct identification of the crystal-of-interaction.
2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2014
For Time-of-Flight (TOF) PET detectors the timing resolution is one of the critical parameters fo... more For Time-of-Flight (TOF) PET detectors the timing resolution is one of the critical parameters for improving image quality. One of the effects degrading the timing resolution is the statistical fluctuation of the number of scintillation photons. The timing degradation is introduced by leading edge discriminator (LED) because the time of crossing the comparator threshold is signal-dependent. It is still possible to correct for this effect by measuring the total number of optical photons and this method is known as walk correction. When the threshold of LED is set very low to achieve the best timing resolution, the energy walk depends on the emitted light in the first ns of scintillation, but not the total integrated number of photons. There is a correlation between the integrated and initial numbers of photons, but the latter number is more significant for energy walk at low threshold. We describe an improved walk correction approach by measuring the rise time at the beginning of the pulse and then compensating the delay variation based on this value, thus improving the timing resolution with a minor increase of the complexity of readout electronics.
Monte-Carlo N-Particle (MCNP) simulations and laboratory prototype testing suggest detection capa... more Monte-Carlo N-Particle (MCNP) simulations and laboratory prototype testing suggest detection capabilities with high energy x-rays of air voids and water defects well past the first well casing. Simulation results show detectability of air voids with diameters less than Ø 0.15" several inches into the concrete structure past the first casing. Laboratory experiments with realistic phantoms using high-energy x(γ)-rays show good discrimination between air voids, water defects, and no defects (cement only). This novel imaging technique is complementary to more conventional inspection modalities such as acoustic or electromagnetic imaging. State-of-the-art acoustic imaging techniques usually investigate the bond between first casing and surrounding cement structure. Current electromagnetic imaging tools typically target detection of material loss in the innermost metal casing but cannot detect defects in the surrounding concrete structure. A high resolution x(γ)-ray imaging modality ...
decentralization? 4 Why did Romania adopt a regionalization process through the extension of the ... more decentralization? 4 Why did Romania adopt a regionalization process through the extension of the competences of the local authorities? 5 What are the results of regional decentralization in France? Is it effi cient? 6 The results of administrative decentralization in Romania. 7 Final considerations. 8 References. RESUMO: Atualmente, governança multinível é o modelo mais adequado para descrever a União Europeia. A participação de atores públicos e privados no processo de tomada de decisão representa um fator fundamental para assegurar efi ciência e responsabilidade nas atividades das autoridades públicas. Este artigo aborda o sistema de governaça multinível a partir da perspectiva da distribuição vertical de competências entre as autoridades central, regional e local. O estudo de caso apresenta o modo em que a governança multinível pode ser implantada nos estados unitários, estruturada em três níveis, através da introdução de um nível intermediário entre os dois níveis já existentes (central e local). Este artigo também analisa o processo de descentralização regional que ocorreu na França, comparando-o com o processo de regionalização ocorrido na Romênia, através da expansão das competências das autoridades locais. Enquanto na França a governança multinível levou à descentralização regional e à transferência de competências para os departamentos e municípios, naquilo que pode ser caracterizado como uma complexa parceria entre o Estado e as três coletividades territoriais, na Romênia o Estado manteve seu caráter centralizado e a transferência de competências para os municípios e distritos ainda é limitada.
The dome with ribs and rings, which covers the ROMEXPO pavilion from Bucharest, was designed afte... more The dome with ribs and rings, which covers the ROMEXPO pavilion from Bucharest, was designed after the collapse of the single layer reticulated dome. In this paper, it was made the checking of the structure, under the dynamic loads with three recorded accelerograms calibrated according to Romanian seismic design code P100-1/2006. Under the action the dynamic loadings, it was made a time-history analysis to determine the zones where the plastic hinges appear, at what accelerations and their position on the structure. The studied dome is formed by 32 spatial semi arches and three rings: one circular ring located at the top of the dome and another two rings, design as trusses, the first near the supports and the second as an intermediate rings above the skylights. Above the skylights up to the top, the dome is tight together with purlins and bracings.
An important part of the reform of the intelligence community is felt in the opening linked with ... more An important part of the reform of the intelligence community is felt in the opening linked with the widening spectrum of methods and spaces which can be used to collect and analyse dates and information. One of these methods that produce large mutations in the system is connected to the world of social media which proves to be a huge source of information. Social Media Intelligence (SOCMINT), the newest member of the family INT's, is undoubtedly a separate domain, a practice rooted in the work of the intelligence community. This paper proposes a general characterization of the most important aspects of Social Media Intelligence, a brand new way for the intelligence community to collect and analyse information for national security purposes (but not only) in the context of the current global challenges. Moreover, the work is focused in identifying the further limitations and opportunities of this practice in the upcoming decade.
The voting behaviour of migrants has been studied extensively but limited attention has been paid... more The voting behaviour of migrants has been studied extensively but limited attention has been paid to how the discussion with families in the home country can be important. This article analyzes under what circumstances migrants influence or are influenced by their families in voting decisions. The analysis uses individual-level data from a survey conducted in 2018 on a sample of 1,839 Romanian migrants. The results indicate that most migrants are not engaged in acts of persuasion about voting. Those who influence their families have a direct interest in the election results, are informed about what happens in the country and are politically active. The migrants who are influenced by their families have limited experience in the countries of residence and strong ties to their home country.
The paper presents the results and the similarity between the experimental test and FEA of a stee... more The paper presents the results and the similarity between the experimental test and FEA of a steel frame connection. The same connection is analyzed in two situations. The second case analyses the connection having some of the elements strengthened in order to increase the capacity of the specimen. The analysis is performed using solid finite element and is compared to the experimental test performed in the laboratory. Several considerations, such as identical conditions for force definition, have to be taken into account in order to obtain good results. Key-Words: deformed shape, strengthen, strain gauge, boundary conditions, stresses.
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016
In PET detector designs, high sensitivity is a critical performance parameter required for obtain... more In PET detector designs, high sensitivity is a critical performance parameter required for obtaining images with reasonable signal-to-noise ratio (SNR). The sensitivity of a PET scanner is primarily determined by the efficiency of detection system (e.g. crystal thickness and solid angle coverage), but could be enhanced by distinguishing and recovering inter-crystal Compton scattering events while maintaining good timing resolution. Generally, identification of such events is based on the measured energies deposited in each crystal; however, the energy performance of SiPM device is affected by the inherent non-linearity of the SiPM response. The measured electric signal exhibits a nonlinear relationship to the number of detected incident photons due to saturation, optical crosstalk, and after pulse. To investigate the sensitivity improvement and timing resolution of inter-crystal Compton scattering events and correct for the presence of saturated SiPM and thus non-linearity in energy...
We describe new high-resolution depth-of-interaction (DOI) PET detector designs based on avalanch... more We describe new high-resolution depth-of-interaction (DOI) PET detector designs based on avalanche photodiodes (APDs). With the development of APDs which utilize thin drift regions to speed response time, these detectors promise improved timing performance relative to previously reported APD-based DOI detectors. The new designs also offer improved decoding of smaller crystals at room temperature through the use of a combination of position-sensitive APDs and pixellated APDs. The number of read-out channels for these designs is kept much smaller than the number of scintillator crystals by ganging together APD outputs in an encoding pattern which still allows for the correct identification of the crystal-of-interaction.
2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2014
For Time-of-Flight (TOF) PET detectors the timing resolution is one of the critical parameters fo... more For Time-of-Flight (TOF) PET detectors the timing resolution is one of the critical parameters for improving image quality. One of the effects degrading the timing resolution is the statistical fluctuation of the number of scintillation photons. The timing degradation is introduced by leading edge discriminator (LED) because the time of crossing the comparator threshold is signal-dependent. It is still possible to correct for this effect by measuring the total number of optical photons and this method is known as walk correction. When the threshold of LED is set very low to achieve the best timing resolution, the energy walk depends on the emitted light in the first ns of scintillation, but not the total integrated number of photons. There is a correlation between the integrated and initial numbers of photons, but the latter number is more significant for energy walk at low threshold. We describe an improved walk correction approach by measuring the rise time at the beginning of the pulse and then compensating the delay variation based on this value, thus improving the timing resolution with a minor increase of the complexity of readout electronics.
Monte-Carlo N-Particle (MCNP) simulations and laboratory prototype testing suggest detection capa... more Monte-Carlo N-Particle (MCNP) simulations and laboratory prototype testing suggest detection capabilities with high energy x-rays of air voids and water defects well past the first well casing. Simulation results show detectability of air voids with diameters less than Ø 0.15" several inches into the concrete structure past the first casing. Laboratory experiments with realistic phantoms using high-energy x(γ)-rays show good discrimination between air voids, water defects, and no defects (cement only). This novel imaging technique is complementary to more conventional inspection modalities such as acoustic or electromagnetic imaging. State-of-the-art acoustic imaging techniques usually investigate the bond between first casing and surrounding cement structure. Current electromagnetic imaging tools typically target detection of material loss in the innermost metal casing but cannot detect defects in the surrounding concrete structure. A high resolution x(γ)-ray imaging modality ...
decentralization? 4 Why did Romania adopt a regionalization process through the extension of the ... more decentralization? 4 Why did Romania adopt a regionalization process through the extension of the competences of the local authorities? 5 What are the results of regional decentralization in France? Is it effi cient? 6 The results of administrative decentralization in Romania. 7 Final considerations. 8 References. RESUMO: Atualmente, governança multinível é o modelo mais adequado para descrever a União Europeia. A participação de atores públicos e privados no processo de tomada de decisão representa um fator fundamental para assegurar efi ciência e responsabilidade nas atividades das autoridades públicas. Este artigo aborda o sistema de governaça multinível a partir da perspectiva da distribuição vertical de competências entre as autoridades central, regional e local. O estudo de caso apresenta o modo em que a governança multinível pode ser implantada nos estados unitários, estruturada em três níveis, através da introdução de um nível intermediário entre os dois níveis já existentes (central e local). Este artigo também analisa o processo de descentralização regional que ocorreu na França, comparando-o com o processo de regionalização ocorrido na Romênia, através da expansão das competências das autoridades locais. Enquanto na França a governança multinível levou à descentralização regional e à transferência de competências para os departamentos e municípios, naquilo que pode ser caracterizado como uma complexa parceria entre o Estado e as três coletividades territoriais, na Romênia o Estado manteve seu caráter centralizado e a transferência de competências para os municípios e distritos ainda é limitada.
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