A New Method to Evaluate the Elastic Behavior of Tablets During Compression

A new method to evaluate elastic/plastic behavior of tablets from tablet compression force-time data is presented. Tablets were compressed in an instrumented eccentric single-punch tablet machine. Equations for the calculation of relative elasticity were derived for both upper and lower punch forces. The experimental work was based on a 3² design having binder solution amount and atomizing air pressure as independent variables. Multilinear stepwise regression analysis was applied in studying the effects of granulation variables. It was concluded that the relative elasticity of tablets is dependent on binder solution amount. Furthermore, this study showed that the relative elasticity parameters can be useful in quantification of elastic behavior of tablets     

Maximum weight independent sets in an infinite plane with uni- and bidirectional interference models

We study the maximum weight independent sets of links between nodes distributed randomly in an infinite plane. Different definitions of the weight of a link are considered, leading to slight variations of what is essentially a spatial reuse problem in wireless multihop networks. A simple interference model is assumed with the interference radius equaling the transmission radius. In addition to unidirectional interference from a transmitter to the receivers of other links, also an RTS/CTS-type bidirectional handshake is considered. We study both the case where the transmission radius is fixed and tunable through power control. With a fixed transmission radius, we derive asymptotic results for the low- and high-density regimes. The main contribution is in the numerical results for the maximum weight, establishing some previously unknown parameters of stochastic geometry. The results are obtained by the Moving Window Algorithm that is able to find the maximum weight independent set in a strip of limited height but unlimited length. By studying the results as a function of the height of the strip, we are able to extrapolate to the infinite plane.     

Modern Microalloyed Steels

The addition of microalloying elements (MAE) to low C-Mn-Si HSLA steels has led to many benefits to the producers,fabricators and end-users.Microstructural improvements such as microstructural refinement,higher dislocation and sub-grain boundary densities and finer M-A-C distributions have led to higher strength,improved toughness and better formability.These improvements can often be traced to the MA addition.In steels for load-bearing applications,the combination of MAE with hardenability additions (Cr,Mo,B,etc.) and lower transformation temperatures has led to much higher strength levels than what were available a few years ago.The resulting nonpolygonal,bainitic and martensitic ferrite microstructures have not only higher strengths but also adequate levels of improved ductility and toughness.Hot strip,plate and pipe applications have benefitted from these developments.Similar improvements have been found in the microalloyed forging steels,where the change from pearlite-ferrite to bainitic ferrite microstructures has led to higher strengths and improved high-cycle fatigue resistance,with little penalty in ductility and toughness.In the cold rolled gauges,both the so-called Advanced High Strength Steels (DP,TRIP and Complex Phase Steels) and the martensitic direct-quenched and press-quenched steels,along with the Interstitial-Free steels,have benefited from MAE additions,especially in the very popular zinc-coated sheet form.This paper will briefly review each of these topic areas,and the underlying physical metallurgy will be discussed.     

Modeling the concept of majority opinion in group decision making

In this paper the problem of group decision making is studied. One of the main issues in this context is to define a decision strategy which takes into account the individual opinions of the decision makers. The concept of majority plays in this context a key role: what is often needed is an overall opinion which synthesizes the opinions of the majority of the decision makers. The reduction of the individual values into a representative value (which we call the majority opinion) is usually performed through an aggregation process. Within fuzzy set theory the concept of majority can be expressed by a linguistic quantifier (such as most), which is formally defined as a fuzzy subset. In this paper we propose two distinct approaches to the definition of a majority opinion. We first consider the case where linguistic quantifiers are associated with aggregation operators which allow us to compute a majority opinion by aggregating the individual opinions. In this case the majority opinion corresponds to the aggregated value. To model this semantics of linguistic quantifiers the IOWA operators are used and a new proposal of definition of their weighting vector is presented. A second method is based on the consideration of the concept of majority as a vague concept. Based on this interpretation we propose a formalization of a fuzzy majority opinion as a fuzzy subset.     

K-means properties on six clustering benchmark datasets

This paper has two contributions. First, we introduce a clustering basic benchmark. Second, we study the performance of k-means using this benchmark. Specifically, we measure how the performance depends on four factors: (1) overlap of clusters, (2) number of clusters, (3) dimensionality, and (4) unbalance of cluster sizes. The results show that overlap is critical, and that k-means starts to work effectively when the overlap reaches 4% level.     

Economic aspects of hybrid cloud infrastructure: User?organization perspective

Adoption of cloud infrastructure promises enterprises numerous benefits, such as faster time-to-market and improved scalability enabled by on-demand provisioning of pooled and shared computing resources. In particular, hybrid clouds, by combining the private in-house capacity with the on-demand capacity of public clouds, promise to achieve both increased utilization rate of the in-house infrastructure and limited use of the more expensive public cloud, thereby lowering the total costs for a cloud user organization. In this paper, an analytical model of hybrid cloud costs is introduced, wherein the costs of computing and data communication are taken into account. Using this model, a cost-efficient division of the computing capacity between the private and the public portion of a hybrid cloud can be identified. By analyzing the model, it can be shown that, given fixed prices for private and public capacity, a hybrid cloud incurs the minimum costs. Furthermore, it is shown that, as the volume of data transferred to/from the public cloud increases, a greater portion of the capacity should be allocated to the private cloud. Finally, the paper illustrates analytically that, when the unit price of capacity declines with the volume of acquired capacity, a hybrid cloud may become more expensive than a private or a public cloud.