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41.
Houses in multiple occupation (HMOs) in which tenants share facilities are housing an increasing proportion of vulnerable adults who have limited affordable housing options. However, knowledge about how these types of property are managed is limited. In this paper, we examine the governance function of HMO landlords from the perspective of landlords/landlord agents and the tenants that live within their properties. The landlord exercises control through formal and informal risk assessment of tenants and close surveillance of them. These control mechanisms may also involve direct or indirect provision of support and care to some tenants. This illustrates the complex relationship between care and control and the extent to which both are integral to the housing management of vulnerable tenants living in HMOs. We suggest that this dual function calls for a critical examination of what constitutes a ‘good landlord’.  相似文献   
42.
Structural and Multidisciplinary Optimization - Controlling the composition of individual voxels allows for a co-optimization of 3D-printed part properties such as color and mechanical ones. As a...  相似文献   
43.
Accurate reporting of sources of income is needed in studies of intergenerational transfers and welfare of the elderly. The objective of this paper is to investigate how memory in the elderly is related to the reporting of remittances received from their children in Thailand. Using data from a longitudinal study of 1036 persons age 60 to 93 in a province in Thailand, the influence of a word recall (verbal learning and recall), and nickname recall (verbal learning and recall) on reporting of remittance was assessed. Initially, both measures were positively and significantly related to the reporting of remittance. The results remained significant only for the nickname task after controlling for education, wealth, living arrangements and disability. The results highlight the importance of cognitive issues in the quality of data and the need for attention to memory in questionnaire design.  相似文献   
44.
Sand dune migration poses serious environmental and social problems for both the infrastructure and communities in the Saudi Arabian Peninsula. In order to monitor and better understand dune migration, a new method is proposed to estimate sand dune displacement/migration by using satellite laser altimetry data from the ICESat mission in the Rub Al-Khali. This method will exploit not only the differences in the observed ICESat elevation profiles, but also the phase differences between two co-located tracks when observed at different times. By using the phase differences, the proposed method will be able to estimate dune displacement vectors with an accuracy of 5 m root mean square. This accuracy has been validated using synthetic data with known displacements. The major causes for dune migration are the wind regime and the type of dunes (e.g. grain size and vegetation cover). A comparison of estimated dune displacement correlated well with the prevailing wind regime during the observation time period. A comparison with satellite imagery revealed that the dune shape and direction (i.e. the representative parameters of dune migration) are in agreement with the estimated displacement vectors. This method represents one of the first attempts to monitor dune migration using space observations only.  相似文献   
45.
In the field of humidity quantities, the first CIPM key comparison, CCT-K6 is at its end. The corresponding European regional key comparison, EUROMET.T-K6, was completed in early 2008, about 4?years after the starting initial measurements in the project. In total, 24 NMIs from different countries took part in the comparison. This number includes 22 EURAMET countries, and Russia and South Africa. The comparison covered the dew-point temperature range from ?50?°C to +20?°C. It was carried out in three parallel loops, each with two chilled mirror hygrometers as transfer standards in each loop. The comparison scheme was designed to ensure high quality results with evenly spread workload for the participants. It is shown that the standard uncertainty due to the long-term instability was smaller than 0.008?°C in all loops. The standard uncertainties due to links between the loops were found to be smaller than 0.025?°C at ?50?°C and 0.010?°C elsewhere. Conclusions on the equivalence of the dew-point temperature standards are drawn on the basis of calculated bilateral degrees of equivalence and deviations from the EURAMET comparison reference values (ERV). Taking into account 16 different primary dew-point realizations and 8 secondary realizations, the results demonstrate the equivalence of a large number of laboratories at an uncertainty level that is better than achieved in other multilateral comparisons so far in the humidity field.  相似文献   
46.
A laser ablation system has been constructed and used to determine the damage threshold of stainless steel, rhodium and single-, poly- and nanocrystalline molybdenum in vacuum, at a number of wavelengths between 220 nm and 1064 nm using 5 ns pulses. All materials show an increase of the damage threshold with decreasing wavelength below 400 nm. Tests in a nitrogen atmosphere showed a decrease of the damage threshold by a factor of 2–3. Cleaning tests have been performed in vacuum on stainless steel samples after applying mixed Al/W/C/D coatings using magnetron sputtering. In situ XPS analysis during the cleaning process as well ex situ reflectivity measurements demonstrate near complete removal of the coating and a substantial recovery of the reflectivity. The first results also show that the reflectivity obtained through cleaning at 532 nm may be further increased by additional exposure to UV light, in this case 230 nm, an effect which is attributed to the removal of tungsten dust from the surface.  相似文献   
47.
The requirements concerning the technical availability as part of the overall equipment effectiveness increase constantly in production nowadays. Unplanned downtimes have to be prevented via efficient methods. Predictive, condition-based maintenance represents a valuable approach for fulfilling these demands, but precise models for state estimation are missing. From the manufacturers’ point of view the challenge consists in wear models with the capability of specifying the correct component’s state as well as providing reliable failure forecasts. Unfortunately, nowadays creation of wear models is based on specific stress tests or design of experiments from the manufacturer. The integration of the production phase or even data feedback and user knowledge does not take place. New potential is promised by cross-cutting technologies from ICT like cloud technologies—in general virtual platform concepts—or approaches of machine learning as enabling technologies. The objective of this paper is to adopt existing algorithms to the new application of condition monitoring in order to evaluate the applicability for automated training of robust wear models. In that context the most commonly used algorithms are described and the reader gets an impression what challenges have to be met when dealing with machine learning. A selection of about ten algorithms with 45 variants is evaluated for four different features within a packaging machine. In the outlook the embedding of the trained model in a cloud architecture is presented.  相似文献   
48.
The titanium condenser has been in operation for 24 years at Amager unit 3 power plant. In February 2012, the plant was contaminated by seawater due to a failed condenser tube and some tubes were plugged. A month later, the plant tripped again. Small leaks were found again and finally approx. 200 tubes were plugged before the condenser was in service again. A series of inspections, NDT, and destructive examinations were conducted to try and understand the cause of failure in the tubes within the condenser. After such investigations, degradation mechanisms such as inner fouling, steam impingement, and fretting/erosion around the supports could be discounted. Ductile cracks were found in the tube within the tubesheet. From circumstantial evidence, it was concluded that failure was caused by a semi-filled condenser which led to a mismatch in expansion coefficients of filled tubes and unfilled tubes during a plant trip. In addition, small amounts of titanium hydride were revealed to be present in the tubes within the tubesheet indicating that the carbon steel tubesheet was corroding due to ingress of salt water. Although this was not the reason for the failure, it indicated the need for repair of the epoxy coating in the waterbox.  相似文献   
49.
50.
The primary goal of optogenetics is the light-controlled noninvasive and specific manipulation of various cellular processes. Herein, we present a hybrid strategy for targeted protein engineering combining computational techniques with electrophysiological and UV/visible spectroscopic experiments. We validated our concept for channelrhodopsin-2 and applied it to modify the less-well-studied vertebrate opsin melanopsin. Melanopsin is a promising optogenetic tool that functions as a selective molecular light switch for G protein-coupled receptor pathways. Thus, we constructed a model of the melanopsin Gq protein complex and predicted an absorption maximum shift of the Y211F variant. This variant displays a narrow blue-shifted action spectrum and twofold faster deactivation kinetics compared to wild-type melanopsin on G protein-coupled inward rectifying K+ (GIRK) channels in HEK293 cells. Furthermore, we verified the in vivo activity and optogenetic potential for the variant in mice. Thus, we propose that our developed concept will be generally applicable to designing optogenetic tools.  相似文献   
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