Guides “bimorphes” d''ondes ultrasoniques “bimorph” ultrasonic wave guides”

An analysis of the dispersion of elastic waves is presented for two types of long ultrasonics wave-guides that we qualify of “bimorph”: (i) a “three-layer” guide made of two different materials and (ii) a “clad core” guide built up of a rectangular core surrounded by a cladding, the materials of the rod and cladding having different properties. An analytical model is proposed to describe the extensional, flexural and torsional motions in “bimorph” wave guides having two geometrical and material symmetry axes. The asymptotic behaviour of the model allows one to select the material properties which lead to modes guided essentially either in the central layer or in the core of the bimorph guide. Moreover, the dispersive properties of a “bimorph” can be controlled through the choice of geometrical and material parameters.     

“Low-Tech” Innovations

This paper is about an industrial sector which, according to the usual socio-scientific indicators, is referred to as “low-tech”, respectively as non-research intensive and which mostly comprises “traditional” industries. The interest in this sector is motivated by the contradictory situation that, on the one hand, the debate about the perspectives of modern societies focuses on the rapidly growing importance of technological innovations, knowledge and research-intensive economic sectors while, on the other hand, traditional industries make up a considerable fraction of employment and production, especially also in developed economies. On the basis of the results of extensive empirical research, this contribution tries to find answers to the basic question, whether one can speak of an innovation mode typical of the low-tech sector. The institutional based innovation systems approach forms the categorical basis of the analysis. In order to elucidate the specific features of low-tech innovations, they are, in conclusion, compared to the general characteristics of high-tech-based innovation processes.     

Differentiation between the terms ”confined masonry“ and ”infill masonry“

This publication concerns the differentiation between the terms ”confined masonry“ and ”infill masonry“ using the example of the national technical approval Z‐17.1‐1145 – POROTON S9 MW –vertically perforated clay units with integrated thermal insulation using thin layer mortar [1].     

“Style” and technology

A rational approach to dealing with the problems created by developing technologies requires a new account of what is involved in proper management. A tripartite distinction is introduced between being reasonable, being rational, and having style. These notions are based on the commonsense principle of rationality (CPR), to be rational one must learn from experience. The proper management of technology requires more than learning from experience (being rational) and having the proper goals (being reasonable); it requires style, which entails being reasonable and acting in accordance with a given standard systematically over time.     

“Snowing” Graphene using Microwave Ovens

Developing a simple and industrially scalable method to produce graphene with high quality and low cost will determine graphene's future. The two conventional approaches, chemical vapor deposition and liquid‐phase exfoliation, require either costly substrates with limited production rate or complicated post treatment with limited quality, astricting their development. Herein, an extremely simple process is presented for synthesizing high quality graphene at low‐cost in the gas phase, similar to “snowing,” which is catalyst‐free, substrate‐free, and scalable. This is achieved by utilizing corona discharge of SiO₂/Si in an ordinary household microwave oven at ambient pressure. High quality graphene flakes can “snow” on any substrate, with thin‐flakes even down to the monolayer. In particular, a high yield of ≈6.28% or a rate of up to ≈0.11 g h^?1 can be achieved in a conventional microwave oven. It is demonstrated that the snowing process produces foam‐like, fluffy, 3D macroscopic architectures, which are further used in strain sensors for achieving high sensitivity (average gauge factor ≈ 171.06) and large workable strain range (0%–110%) simultaneously. It is foreseen that this facile and scalable strategy can be extended for “snowing” other functional 2D materials, benefiting their low‐cost production and wide applications.     

A Rebuttal to The “Reply”

At the outset a brief background from a pharmaceutics perspective is presented here. Pharmaceutical industry is one of the most tightly regulated industries. Statistics naturally plays an important role in the implementation of the compendial, regulatory and in-house requirements. The minimal requirement consists of a set of basic statistics, such as mean and standard deviation (SD), associated with each group of sample experimental data intended for submission. However, not only each statistic is individually subjected to a set of compendial, regulatory and in-house specifications, but also the individual observation is required to be within specific range for compliance (e.g. content uniformity). Hence these basic statistics are often referred to as the stand-alone sample (SAS) statistics, meaning that each statistic has to meet its own requirements. In this context, the geometric mean is indeed a SAS statistic. It is meaningful and interpretable directly from its face value. The geometric standard deviation (GSD) as derived in ref(B) is also a (SAS) statistic. It is meaningful and easily interpretable directly from its face value. It has the same sample information and the same interpretation as that of the regular SD. Sometimes, it shares essentially the same magnitude as the regular SD. Besides, it also has essentially the same magnitude as that of the jackknife GSD statistic, GSD(JK). For decades, these geometric statistics have been in practice, particulary, since the author of ref(B) was a member of the USP In-Vitro Bioavailability Testing Subcommittee (1970-1975). It has also been accepted fully and freely by the above-mentioned over-sight agencies.