220 research outputs found
Intervention for children exposed to interparental violence: A randomized controlled trial of effectiveness of specific factors, moderators and mediators in community-based intervention
Get PDFSchuengel, C. [Promotor]Lamers, F. [Promotor]Schipper, J.C. de [Copromotor
The impact of child sexual abuse on children and their families: The role of mother-child emotion dialogues, secrecy, disgust sensitivity, and social connectedness
Get PDFFinkenauer, C. [Promotor]Lamers, F. [Promotor]Schipper, J.C. de [Copromotor
The impact of destructive parental conflicts on children and their families: The role of parental availability, mother-child emotion dialogues, and forgiveness
Get PDFFinkenauer, C. [Promotor]Lamers, F. [Promotor]Schipper, J.C. de [Copromotor
Exploring attachment behavior versus non-attachment behavior: Issues in the clinical assessment of relationships with significant caregivers
No full textKoers bepalen. Een onderzoek naar toekomstige ontwikkelingen in de binnenvaart en de strategische keuzemogelijkheden voor logistiek dienstverlener Peterson.
No full textTechnology, Policy and Managemen
Long term nitrate removal in a denitrification wall
No full textNitrogen (N) inputs to groundwater are one of the most widespread environmental problems globally. However, as N is important for crop production to support the current global population, it is difficult to limit N input to an extent where groundwater contamination is completely avoided. Researchers have been testing new ways to remove N (in the form of nitrate (NO3-)) from groundwater, primarily through enhancing microbial denitrification. One technology utilizing this microbial process is a denitrification wall, which is an inexpensive, low-maintenance technology compared to other options to treat NO3--contaminated groundwater. Denitrification walls have been shown to be effective for removing NO3- from groundwater through denitrification for seven years in New Zealand, nine years in Iowa, and 15 years in Canada; however, long-term data on the efficacy of denitrification walls remain limited. In order to understand how these systems function in the long term, the performance of a New Zealand denitrification wall installed in 1996 was examined. Field sampling was carried out during the winter of 2010 at the denitrification wall at Bardowie Farm in Cambridge, New Zealand. This farm had received relatively high N inputs from spray-irrigation of effluent from the nearby Hautapu Dairy Factory for over 30 years. The denitrification wall was originally constructed by mixing 40 m3 Pinus radiata sawdust with soil down to a depth of 1.5 m where it intercepted groundwater flow. Groundwater samples were collected from wells installed upslope and within the wall and samples were analyzed for NO3- concentrations on five occasions. Soil samples were collected on four occasions from below the water table and analyzed for denitrifying enzyme activity (DEA), total carbon (C), available C, and microbial biomass C. Results were compared to previous measurements. Groundwater NO3- concentrations entering the wall averaged 2.6 mg N L-1, which was a decrease from 2002 where NO3- entered the wall at an average of 9 mg N L-1. Despite this decrease, NO3- concentrations within the wall averaged 0.2 mg N L-1, which corresponded to 92% NO3- removal. DEA rates in the wall were nearly as high as the first year of construction. In contrast, total C and microbial biomass C had decreased by half, while available C remained the same as measured two years after construction. Denitrification in the wall remained NO3- limited suggesting that C was still sufficiently available to the denitrifiers. These data indicated that the denitrification wall was still effective after 14 years. To predict denitrification wall longevity, a first-order decay curve was fitted to the total C data through time (R2 = 0.92; p < 0.05). The decay curve was used to predict the time until total C reached 0.1%, although it is unclear at what %C denitrification will become C limited. Using this decay curve, it was estimated that C in the wall would not be depleted for 66 years, although it is possible that C will become limiting to denitrifiers before that time. This long-term study suggested that denitrification walls are cost-effective solutions to removing NO3- from groundwater as they can be effective for a number of years without any maintenance
Associated factors of disturbances of attachment in preschool children living in foster families
No full textDouble curved precast load bearing concrete elements
No full textThe construction of free form building stagnated, due to the high construction cost of it. Double curved surfaces are only applied at projects with a high profile and projects above average budget during years. The problem with double curved surfaces is mainly the formwork. The present days used techniques to construct these formworks are statically. For example: wooden, steel or milled EPS formwork could only be used for one shaped elements. The lack of repetition and so the reusability of the formwork, which means that for a free form surface for every element a unique formwork is needed, makes the construction very expensive. A feasible way for mass production of unique shaped double curved elements could be achieved by a flexible formwork: a formwork that can be adjusted in every desired shape. It consists of a flexible layer that can be deformed into the desired curved surface by adjusting for example pistons, actuators or pins. Recently K. Huyghe and A. Schoofs have executed a series of experiments with a flexible formwork, build earlier by D. Rietbergen and Dr. Ir. K. Vollers. The purpose of this master thesis was to solve more aspects of the flexible formwork, and to make it a feasibly system. The main focus was the behavior of the flexible layer, at some places the flexible layer did not though the actuators. Predicting the behavior of the deformed flexible layer makes an accurate production possible. To be able to determine the behavior of the flexible layer some models are proposed. With these models the reaction forces at the supports could be determined, compression forces means that the flexible layer though the supports. The first model that is proposed, is for a single curved element. For the double curved mould surface two models are proposed, a plate model and a strip model. With tests at the Stevin Laboratory these models are verified, and some other aspects are tested, for example the flexible border of the formwork. Tests indicate that a plate is not suitable for the flexible layer, it buckles due to the plate stresses. The strip mould consists of two layers of strips, perpendicular to each other. The top layer of the strips is the mould surface. Tests showed that it is possible to produce double curved elements with the strip mould. Conclusions and recommendations. The models that are proposed in this thesis describe the behavior of the flexible layer well. A plate does not fulfil the function of a flexible layer. Tests have shown that it is possible to produce double curved elements with the strip mould as flexible layer. To cover the strips an additional layer is needed. In these tests polyether is used, as well for the borders. The protection of the polyether with sealant made the concrete element very rough. Another material has to be found as elastic layer, or to protect the polyether.Design and ConstructionCivil Engineering and Geoscience
Sustainable Facades for the Energy Museum
No full textDesign and ConstructionCivil Engineering and Geoscience
Precast 2010: Assembling Freeform Buildings in Precast Concrete
No full textDesign and ConstructionCivil Engineering and Geoscience
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