Provably-Secure Time-Bound Hierarchical Key Assignment Schemes

A time-bound hierarchical key assignment scheme is a method to assign time-dependent encryption keys to a set of classes in a partially ordered hierarchy, in such a way that each class can compute the keys of all classes lower down in the hierarchy, according to temporal constraints.     

Incidence and Correlates of Diarrhea, Fever, Malaria and Weight Loss Among Elderly and Non-Elderly Internally Displaced Parents in Cibombo Cimuangi in the Eastern Kasai Province, Democratic Republic of the Congo

Socio-demographic and medical information about internally displaced persons in all parts of the world is lacking. One area where many of these persons reside is the Democratic Republic of Congo. A cross-sectional survey was used to assess the differences, if any, between elderly and non-elderly internally displaced parents in Cibombo Cimuangi, a resettlement community in the Eastern Kasai province. The survey was undertaken in 2005. Adults members from these households provided data on the experience of disease episodes over a six-month period and demographic information. Elderly internally displaced parents (older than 60 years) and non-elderly displaced parents were compared in number of illnesses (e.g., fever, weight loss) and selected demographic variables. These groups are similar in terms of experience of disease, but significantly different in terms of level of spouse's education and concentration of adult children in the household. Adjusting for these two demographic variables did not change the experience of illness for either type of parents. We discussed reasons for the absence of differences in disease incidence between the two groups and several factors that will impact internally displaced persons in Africa in the future.     

Analyzing visually impaired people’s touch gestures on smartphones

Multimedia Tools and Applications - We present an analysis of how visually impaired people perform gestures on touch-screen smartphones and report their preferences, explaining the procedure and...     

Reinigung vor der Beschichtung

Cleaning before coating — the last step of the manufacturing process Before coating the surface of the component which shall be coated is cleaned. Several machines and chemicals can be used. After the cleaning the surface must be ready for coating. The influence of the machining parameters on the surface of a component is shown. The effectiveness of the cleaning processes prior to coating is discussed, and put in context to the whole manufacturing process. A classification of the manufacturing process should not be based on the different locations where it takes place. All the machining steps which influence the properties and the coat ability of the metal surface should be considered as connected. All these treatment steps are ideally tuned in a way that the surface can be coated flawlessly.     

Remote cutting of Li-ion battery electrodes with infrared and green ns-pulsed fibre lasers

Thin sheet anode and cathode materials made in composite structures constitute some of the most important components of a Li-ion battery. These materials are currently cut by punching technology, which shows degrading behaviour as the tool wears out. A viable option for Li-ion battery electrode manufacturing is the use of remote laser cutting. However, the operation requires fulfilling both productivity and quality aspects to substitute the conventional production method. One of the most critical aspects in quality is the clearance width, which is defined as the extent of the exposed middle layer of the sandwich at the laser cut kerf. This work investigates the quality aspects of laser cutting of Li-ion electrodes when a green fibre laser source (λ?=?532 nm, τ?=?1 ns) is used rather than the more traditional infrared (IR) fibre laser source (λ?=?1,064 nm, τ?=?250 ns). The processing conditions were investigated to reveal the technological feasibility zones. Clearance width was studied within the technological feasibility zones for all the material-laser combinations. Results showed that high productivity criterion is met by the IR system, since cutting speed could reach 30 m/min with 54 W average laser power on both anode and cathode. On the other hand, the green laser provided clearance width below 20 μm. In the best case, the clearance on anode could be eliminated with the green laser system. Although the maximum cutting speed was 4.5 m/min, upscaling of green laser power can provide required productivity.     

彩虹·洞——巴塞罗那Imaginarium儿童产品旗舰店

儿童总是喜爱玩耍的，神秘的洞穴更是对他们有着无穷的吸引力。在孩子的眼中，色彩是丰富世界的一个缩影。因此，迫庆一郎先生在设计巴塞罗那儿童品牌Imaginarium旗舰店时，就以洞穴·彩虹作为了设计的主题。     

Review: tailoring the properties of macroporous carbon foams

Carbon foams are non-toxic, highly porous, light materials which demonstrate a wide range of properties. That fact allows carbon foams to be applied in many areas of life, ranging from electronics industry, through machinery, car and construction industry, to environmental protection. The properties of carbon foams are closely connected with their density, and its value is especially influenced by their internal structure, i.e. mainly size and number of pores, pore wall thickness and structural order of solid matrix. That is why it is possible to design the properties of carbon foams by controlling their growth. The main control factors are selecting the suitable raw material, the process parameters (temperature and pressure) and the suitable production method. Additionally, the properties of carbon foams may be modified by doping them with carbon or mineral fillers. The second method is the enrichment of carbon matrix with heteroatoms, mainly of boron and nitrogen. This paper presents the review of the possibilities of tailoring the structure and properties of carbon foams, based on the current level of knowledge available in the literature.