Constraints on cosmic strings using data from the first Advanced LIGO observing run

Cosmic strings are topological defects which can be formed in grand unified theory scale phase transitions in the early universe. They are also predicted to form in the context of string theory. The main mechanism for a network of Nambu-Goto cosmic strings to lose energy is through the production of loops and the subsequent emission of gravitational waves, thus offering an experimental signature for the existence of cosmic strings. Here we report on the analysis conducted to specifically search for gravitational-wave bursts from cosmic string loops in the data of Advanced LIGO 2015-2016 observing run (O1). No evidence of such signals was found in the data, and as a result we set upper limits on the cosmic string parameters for three recent loop distribution models. In this paper, we initially derive constraints on the string tension Gμ and the intercommutation probability, using not only the burst analysis performed on the O1 data set but also results from the previously published LIGO stochastic O1 analysis, pulsar timing arrays, cosmic microwave background and big-bang nucleosynthesis experiments. We show that these data sets are complementary in that they probe gravitational waves produced by cosmic string loops during very different epochs. Finally, we show that the data sets exclude large parts of the parameter space of the three loop distribution models we consider

Research design for investigation of Nigeria manufacturing management

Nigeria is a developing nation in West Africa and the manufacturing management in this nation in the past twenty years has not been well documented. This paper sets out the research design for investigating Nigeria manufacturing management. The project is a combination of 'explanatory and exploratory researches' because it strives to explore the issues related to the Nigerian manufacturing organizations with the help of the existing research studies as well as statistical survey work

Discovery of elements 113 - 118

Review of discovery and investigation of isotopes of elements 113-118 produced in the reactions of 48 Ca with target nuclei 238U-249Cf is presented. The synthesis of the heaviest nuclei, their summary decay properties, and methods of identification are discussed. The radioactive properties of the new nuclei give evidence of the significant increase of the stability of the heavy nuclei with rise of their neutron number and approaching magic number N=184

Standardising the elimination of unnecessary data from interview transcripts for the purposes of knowledge-based systems - A case study

Although knowledge elicitation, the process of extracting knowledge from human experts to be incorporated into a knowledge-based system, has been the subject of some notable studies, less attention has been paid to the methods of analysing the raw data once it has been extracted from the expert. When knowledge elicitation sessions are interview-based, the resultant form of raw data is usually a transcript of the interviewee's utterances. This paper describes an investigation into the preliminary stage of analysing such transcripts. It outlines the development of an approach to eliminate unnecessary detail from interview transcripts, thus enabling attention to be focused upon the remaining, more relevant data via a simple technique based upon cheap and readily available technology. The paper then outlines a rapid-prototyping approach for evaluating this method, the results of which were felt to be very encouraging