The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform
Tk Logan - One of the best experts on this subject based on the ideXlab platform.
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Cumulative victimization, psychological distress, and high-risk behavior among substance-involved women.
Violence & Victims, 2011Co-Authors: Seana Golder, Tk LoganAbstract:This research addressed two questions: (a) What is the relationship between different patterns of cumulative victimization and psychological distress? And (b) How does the pattern of cumulative victimization and psychological distress influence women's engagement in substance- and sex-related risk behavior? Data were analyzed from interviews with 149 sexually Active, Crack-using women who completed a follow-up interview after participating in the Kentucky National Institute on Drug Abuse (NIDA) AIDS Cooperative Agreement. Findings from the multivariate analyses indicated that victimization accounted for 5% and 39% of the variance in psychological distress and high-risk behavior, respectively; cumulative victimization and psychological distress accounted for 6% to 11% of the variance in the high-risk behaviors. Results highlight the affects of childhood and adult victimization on psychological distress and the associations between different types of psychological distress and risk behavior.
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Correlates and Predictors of Women’s Sex Trading Over Time among a Sample of Out-of-treatment Drugs Abusers
AIDS and Behavior, 2007Co-Authors: Seana Golder, Tk LoganAbstract:This research addressed two research questions: (a) controlling for Crack use, what are the factors associated with women’s engagement in ever having traded sex? and (b) controlling for Crack use, what are the factors associated with women’s engagement in sex trading in the past 90 days? The sample included 149 sexually Active, Crack using women selected from a subsample of participants in the Kentucky NIDA AIDS Cooperative Agreement. Bivariate analyses indicated that in addition to the pattern of Crack use, 13 of the candidate variables were significantly related to sex trading, ever and 11 related to sex trading in the past 90 days. The multivariate models accounted for more than 40% of the variance in sex trading, ever and almost 59% of the variance in sex trading over the past 90 days. Suggestions for HIV/AIDS prevention and intervention among drug-involved women are discussed; implications for future research are suggested.
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Correlates and predictors of women's sex trading over time among a sample of out-of-treatment drugs abusers.
Aids and Behavior, 2006Co-Authors: Seana Golder, Tk LoganAbstract:This research addressed two research questions: (a) controlling for Crack use, what are the factors associated with women’s engagement in ever having traded sex? and (b) controlling for Crack use, what are the factors associated with women’s engagement in sex trading in the past 90 days? The sample included 149 sexually Active, Crack using women selected from a subsample of participants in the Kentucky NIDA AIDS Cooperative Agreement. Bivariate analyses indicated that in addition to the pattern of Crack use, 13 of the candidate variables were significantly related to sex trading, ever and 11 related to sex trading in the past 90 days. The multivariate models accounted for more than 40% of the variance in sex trading, ever and almost 59% of the variance in sex trading over the past 90 days. Suggestions for HIV/AIDS prevention and intervention among drug-involved women are discussed; implications for future research are suggested.
Seana Golder - One of the best experts on this subject based on the ideXlab platform.
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Cumulative victimization, psychological distress, and high-risk behavior among substance-involved women.
Violence & Victims, 2011Co-Authors: Seana Golder, Tk LoganAbstract:This research addressed two questions: (a) What is the relationship between different patterns of cumulative victimization and psychological distress? And (b) How does the pattern of cumulative victimization and psychological distress influence women's engagement in substance- and sex-related risk behavior? Data were analyzed from interviews with 149 sexually Active, Crack-using women who completed a follow-up interview after participating in the Kentucky National Institute on Drug Abuse (NIDA) AIDS Cooperative Agreement. Findings from the multivariate analyses indicated that victimization accounted for 5% and 39% of the variance in psychological distress and high-risk behavior, respectively; cumulative victimization and psychological distress accounted for 6% to 11% of the variance in the high-risk behaviors. Results highlight the affects of childhood and adult victimization on psychological distress and the associations between different types of psychological distress and risk behavior.
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Correlates and Predictors of Women’s Sex Trading Over Time among a Sample of Out-of-treatment Drugs Abusers
AIDS and Behavior, 2007Co-Authors: Seana Golder, Tk LoganAbstract:This research addressed two research questions: (a) controlling for Crack use, what are the factors associated with women’s engagement in ever having traded sex? and (b) controlling for Crack use, what are the factors associated with women’s engagement in sex trading in the past 90 days? The sample included 149 sexually Active, Crack using women selected from a subsample of participants in the Kentucky NIDA AIDS Cooperative Agreement. Bivariate analyses indicated that in addition to the pattern of Crack use, 13 of the candidate variables were significantly related to sex trading, ever and 11 related to sex trading in the past 90 days. The multivariate models accounted for more than 40% of the variance in sex trading, ever and almost 59% of the variance in sex trading over the past 90 days. Suggestions for HIV/AIDS prevention and intervention among drug-involved women are discussed; implications for future research are suggested.
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Correlates and predictors of women's sex trading over time among a sample of out-of-treatment drugs abusers.
Aids and Behavior, 2006Co-Authors: Seana Golder, Tk LoganAbstract:This research addressed two research questions: (a) controlling for Crack use, what are the factors associated with women’s engagement in ever having traded sex? and (b) controlling for Crack use, what are the factors associated with women’s engagement in sex trading in the past 90 days? The sample included 149 sexually Active, Crack using women selected from a subsample of participants in the Kentucky NIDA AIDS Cooperative Agreement. Bivariate analyses indicated that in addition to the pattern of Crack use, 13 of the candidate variables were significantly related to sex trading, ever and 11 related to sex trading in the past 90 days. The multivariate models accounted for more than 40% of the variance in sex trading, ever and almost 59% of the variance in sex trading over the past 90 days. Suggestions for HIV/AIDS prevention and intervention among drug-involved women are discussed; implications for future research are suggested.
Moreno Arostegui, Jua Manuel - One of the best experts on this subject based on the ideXlab platform.
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An architecture for real-time arbitrary and variable sampling rate conversion with application to the processing of harmonic signals
2020Co-Authors: Galindo Guarch, Francisco Javie, Audrenghie Philippe, Moreno Arostegui, Jua ManuelAbstract:The paper presents a new solution for sampling rate conversion and processing of harmonic signals with known but possibly varying fundamental frequency. This problem is commonly found in particle accelerators, for tracking the beam signals whose revolution frequency varies during the acceleration ramp. It is also common among many other fields such as speech and music processing, removal of mechanical noises, filtering of biomedical recordings, Active Crack imaging, etc. The key element in the proposed solution is a new architecture for a Farrow-based resampler, in which the resampling ratio can take any value and can be modified continuously to follow the signal fundamental frequency. The combination of two complementary resamplers creates a processing region where signal synchronous processing is performed. The resampler architecture is optimized for modern FPGA features. It decouples the processing and sampling clocks, and uses a single processing (hardware) clock whose frequency remains fixed. The functional model was migrated to Xilinx System Generator and the overall performance is evaluated with an application that filters a periodic signal whose frequency follows a known linear ramp in the presence of additive white noise.The authors would like to thank CERN colleagues in BE-RF-FB section, plus K. Smith’s group at BNL, T. Mastoridis at California Polytechnic State University, C. Rivetta at SLAC and F. Tamura from J-PARC for the many fruitful discussions. Special thanks to A. Butterworth and R. Borner at CERN BE-RF for proofreading the paper.Peer Reviewe
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An architecture for real-time arbitrary and variable sampling rate conversion with application to the processing of harmonic signals
'Institute of Electrical and Electronics Engineers (IEEE)', 2020Co-Authors: Galindo Guarch, Francisco Javie, Audrenghie Philippe, Moreno Arostegui, Jua ManuelAbstract:The paper presents a new solution for sampling rate conversion and processing of harmonic signals with known but possibly varying fundamental frequency. This problem is commonly found in particle accelerators, for tracking the beam signals whose revolution frequency varies during the acceleration ramp. It is also common among many other fields such as speech and music processing, removal of mechanical noises, filtering of biomedical recordings, Active Crack imaging, etc. The key element in the proposed solution is a new architecture for a Farrow-based resampler, in which the resampling ratio can take any value and can be modified continuously to follow the signal fundamental frequency. The combination of two complementary resamplers creates a processing region where signal synchronous processing is performed. The resampler architecture is optimized for modern FPGA features. It decouples the processing and sampling clocks, and uses a single processing (hardware) clock whose frequency remains fixed. The functional model was migrated to Xilinx System Generator and the overall performance is evaluated with an application that filters a periodic signal whose frequency follows a known linear ramp in the presence of additive white noise.The authors would like to thank CERN colleagues in BE-RF-FB section, plus K. Smith’s group at BNL, T. Mastoridis at California Polytechnic State University, C. Rivetta at SLAC and F. Tamura from J-PARC for the many fruitful discussions. Special thanks to A. Butterworth and R. Borner at CERN BE-RF for proofreading the paper.Peer ReviewedPostprint (published version
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An Architecture for Real-Time Arbitrary and Variable Sampling Rate Conversion With Application to the Processing of Harmonic Signals
'Institute of Electrical and Electronics Engineers (IEEE)', 2020Co-Authors: Guarch, Fco Javie Galindo, Audrenghie Philippe, Moreno Arostegui, Jua ManuelAbstract:The paper presents a new solution for sampling rate conversion and processing of harmonic signals with known but possibly varying fundamental frequency. This problem is commonly found in particle accelerators, for tracking the beam signals whose revolution frequency varies during the acceleration ramp. It is also common among many other fields such as speech and music processing, removal of mechanical noises, filtering of biomedical recordings, Active Crack imaging, etc. The key element in the proposed solution is a new architecture for a Farrow-based resampler, in which the resampling ratio can take any value and can be modified continuously to follow the signal fundamental frequency. The combination of two complementary resamplers creates a processing region where signal synchronous processing is performed. The resampler architecture is optimized for modern FPGA features. It decouples the processing and sampling clocks, and uses a single processing (hardware) clock whose frequency remains fixed. The functional model was migrated to Xilinx System Generator and the overall performance is evaluated with an application that filters a periodic signal whose frequency follows a known linear ramp in the presence of additive white noiseThe paper presents a new solution for sampling rate conversion and processing of harmonic signals with known but possibly varying fundamental frequency. This problem is commonly found in particle accelerators, for tracking the beam signals whose revolution frequency varies during the acceleration ramp. It is also common among many other fields such as speech and music processing, removal of mechanical noises, filtering of biomedical recordings, Active Crack imaging, etc. The key element in the proposed solution is a new architecture for a Farrow-based resampler, in which the resampling ratio can take any value and can be modified continuously to follow the signal fundamental frequency. The combination of two complementary resamplers creates a processing region where signal synchronous processing is performed. The resampler architecture is optimized for modern FPGA features. It decouples the processing and sampling clocks, and uses a single processing (hardware) clock whose frequency remains fixed. The functional model was migrated to Xilinx System Generator and the overall performance is evaluated with an application that filters a periodic signal whose frequency follows a known linear ramp in the presence of additive white noise
Nele De Belie - One of the best experts on this subject based on the ideXlab platform.
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Novel Active Crack width control technique to reduce the variation on water permeability results for self-healing concrete
Construction and Building Materials, 2019Co-Authors: Tim Van Mullem, Elke Gruyaert, Brenda Debbaut, Robby Caspeele, Nele De BelieAbstract:Abstract An important characteristic of self-healing concrete is its ability to regain liquid tightness after it has been damaged. This ability can be tested using water permeability setups. However, a lack of standardized test methods makes it difficult to compare results between different studies. Additionally, the large variation on Crack widths between specimens results in a large spread of the permeability results. This, together with all other factors (e.g. internal Crack geometry) contributing to the variability of permeability results, should be clearly assessed in order to develop a standardized permeability test. In this study a new Active Crack width control technique has been developed to significantly reduce the variation on the Crack width within a series of specimens, resulting in more consistent permeability results. By analysing permeability results of specimens from test series with different nominal Crack widths the factors contributing to variability could be assessed. The two main contributors are the variability on the mean Crack width at the Crack mouth and the variability on the internal Crack geometry. The variability of the mean Crack width can induce a 3 times higher variability of the permeability results. In contrast to the Crack width, the internal geometry of a Crack cannot be determined directly, yet it can cause a difference in permeability of more than 25% for specimens with an identical nominal surface Crack width. It can be concluded that when Crack widths are Actively controlled, the main source of variability on permeability results is the internal geometry which cannot be controlled, regardless of the chosen Cracking technique. In order to reduce the variance on the mean permeability, it is proposed to use at least six specimens per series.
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Influence of Active Crack width control on the chloride penetration resistance and global warming potential of slabs made with fly ash + silica fume concrete
Construction and Building Materials, 2014Co-Authors: Philip Van Den Heede, Mathias Maes, Nele De BelieAbstract:Abstract Service life predictions for concrete exposed to chloride-induced corrosion usually result from durability tests performed on unCracked concrete. Chloride migration coefficients for unCracked concrete should only be used if the structure can be considered as unCracked. The seemingly unCracked condition requires Crack widths below 0.1 mm. The extra reinforcing steel to achieve this in concrete slabs, results in a 30–43% increase of the global warming potential. Fly ash + silica fume concrete may be preferred because of its low 28 day migration coefficient (3.4 × 10−12 m2/s), its long service life (>100 years) and its autogenous healing ability.
De Belie Nele - One of the best experts on this subject based on the ideXlab platform.
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Sealing efficiency of cement-based materials containing extruded cementitious capsules
'Elsevier BV', 2020Co-Authors: Anglani Giovanni, Van Mullem Tim, De Belie Nele, Zhu Xuejiao, Wang Jianyun, Antonaci Paola, Tulliani, Jean Marc Christian, Van Tittelboom KimAbstract:The intensive use of cement-based building materials is a growing concern in terms of environmental impact, since they significantly contribute to the global anthropogenic CO2 emissions. The development of self-sealing cementitious materials could be a possible approach to improve the structural durability and thus reduce overall cost and environmental impact. In the present work, the efficiency of a self-sealing system using extruded cementitious capsules was experimentally investigated, and different healing agents were tested (specifically, a water-repellent agent, a polyurethane precursor and a solution of silica gel immobilized ureolytic bacteria). The self-sealing efficiency was evaluated in terms of capability to autonomously seal localized Cracks induced in a controlled way. An Active Crack width control technique was adopted during the Cracking procedure, in order to reduce the variation of the Crack width within a series of specimens. Water permeability and capillary water absorption tests were performed to quantify the Crack sealing ability, along with qualitative visual analysis of the Crack faces. Positive results were achieved when using the water-repellent agent in water absorption tests, the bacterial agent in water-flow tests and the polyurethane precursor in both cases. This suggests that the proposed self-sealing system is sufficiently versatile to be used with different healing agents and that it can be effective in prolonging the material functionality by selecting the most appropriate agent for the real operating conditions
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Variation on water permeability results of self-healing concrete studied by Active Crack width control technique
2019Co-Authors: Van Mullem Tim, Gruyaert Elke, Debbaut Brenda, Caspeele Robby, De Belie NeleAbstract:The durability of concrete can be greatly increased by the addition of self-healing agents which are able to close Cracks without the need for external human intervention. The result of the Crack closure is a regain in liquid tightness called sealing. The sealing efficiency of self-healing concrete and mortars can be assessed by permeability tests. However, there is often a large spread on the results of these tests which is mostly attributed to Crack widths of tested specimens being outside of the intended Crack width range. This large spread on the permeability makes a comparison between results of different studies challenging. Using an in-house developed Active Crack width control technique allowed to significantly reduce the variation on the mean width of bending Cracks. This paper reports on the contributing factors to the variation on permeability results by studying several series of mortar specimens with a different nominal Crack width. It was found that the two most contributing factors to the variation on the permeability results are the variability of the mean Crack width and the variability of the internal Crack geometry between different specimens. The variation on the mean Crack width influences the variation on the permeability with a multiplication factor of 3. On the other hand, for specimens with the same nominal Crack width, the difference in permeability can still be more than 25% due to thevariation on the internal Crack geometry. Reducing the variability of the internal Crack geometry is not straightforward. Yet, it can be concluded that increasing the sample size from 3 to 6 specimens per series can reduce the variation on the mean permeability by 30%. This kind of reduction will contribute to a standardization of the permeability tests used for self-healing concrete
