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Engineering design research manifests as a platform for exploration, description, arrangement, rationalization, and application of design knowledge. What we can see when we are looking at the research into engineering design is an almost chaotically fragmented picture. Is it possible to have a holistic view on the contents and internal relationships of engineering design research? This paper considers teleology, a reflection of a branch of philosophical speculations, as the doctrine of ordering knowledge of engineering design and structuring engineering design research accordingly. Teleology explains that the ultimate reason behind design is to sustain human existence and well being by virtual creation of artifacts and services for society. To this end, knowledge of engineering research is supposed to be transferred from the platform of scientific/theoretical exploration and comprehension to the platform of technical/pragmatic application. This implies a natural streaming of knowledge of engineering design. In order to make the teleological explanation operational, a framework of reasoning has been constructed by adopting the analogy of the source, channel and sink of a stream. To represent the source, channel and sink categories of engineering design knowledge, the author inaugurated nine categories in the framework. It has been hypothesized that the introduced categories are equally valid for research in engineering design as well as for the knowledge of engineering design. Within each category, research domains and trajectories have been defined. The proposed teleology-based framework lends itself to a better understanding of the disciplinary articulation and intrinsic relationships of engineering design research. It is hoped, among other things, to form a basis for a shared understanding, to make the influence of decisions on research programs more transparent, as well as to facilitate organizing subject materials for various design courses.

Gamma-ray bursts are usually classified into either short-duration or long-duration bursts. Going beyond the short-long classification scheme, it has been shown on statistical grounds that a third, intermediate population is needed in this classification scheme. We are looking for physical properties which discriminate the intermediate duration bursts from the other two classes. As the intermediate group is the softest, we argue that we have related them with X-ray flashes among the GRBs. We give a new, probabilistic definition for this class of events.

In the case of Gamma Ray Bursts with measured redshift, we can calculate the k-correction to get the fluence and energy that were actually produced in the comoving system of the GRB. To achieve this we have to use well-fitted parameters of GRB spectrum, available in the GCN database. The output of the calculations is the comoving isotropic energy Eiso, but this is not the endpoint: this data can be useful forestimating the ΩM parameter of the Universe and for making a GRB Hubble diagram usig Amati's relation.

We studied the complete randomness of the angular distribution of BATSE gamma-ray bursts (GRBs). Based on their durations and peak fluxes, we divided the BATSE sample into 5 subsamples (short1, short2, intermediate, long1, long2) and studied the angular distributions separately. We used three methods to search for non-randomness in the subsamples: Voronoi tesselation, minimal spanning tree, and multifractal spectra. To study any non-randomness in the subsamples we defined 13 test-variables (9 from Voronoi tesselation, 3 from the minimal spanning tree and one from the multifractal spectrum). We made Monte Carlo simulations taking into account the BATSE's sky-exposure function. We tested therandomness by introducing squared Euclidean distances in the parameter space of the test-variables. We recognized that the short1, short2 groups deviate significantly (99.90%, 99.98%) from the fully random case in the distribution of the squared Euclidean distances but this is not true for the long samples. In the intermediate group, the squared Euclidean distances also give significant deviation (98.51%).

The Fermi satellite has a particular motion during its flight which enables it to catch the gamma-ray bursts mostly well. The side-effect of this favourable feature is that the lightcurves of the GBM detectors are stressed by rapidly and extremely varying background. Before this data is processed, it needs to be separated from the background. The commonly used methods [3,7] were useless for most cases of Fermi, so we developed a new technique based on the motion and orientation of the satellite. The background-free lightcurve can be used to perform statistical surveys, hence we showed the efficiency of our background-filtering method presenting a statistical analysis known from the literature.

Both short and intermediate gamma-ray bursts are distributed anisotropically in the sky (Mészáros, A. et al. ApJ, 539, 98 (2000), Vavrek, R. et al. MNRAS, 391, 1 741 (2008)). Hence, in the redshift range, where these bursts take place, the cosmological principle is in doubt. It has already been noted that short bursts should be mainly at redshifts smaller than one (Mészáros, A. et al. Gamma-ray burst: Sixth Huntsville Symp., AIP, Vol. 1 133, 483 (2009); Mészáros, A. et al. Baltic Astron., 18, 293 (2009)). Here we show that intermediate bursts should be at redshifts up to three.