Birth and death processes with neutral mutations

In this paper, we review recent results of ours concerning branching processes with general lifetimes and neutral mutations, under the infinitely many alleles model, where mutations can occur either at birth of individuals or at a constant rate during their lives. In both models, we study the allelic partition of the population at time t. We give closed formulae for the expected frequency spectrum at t and prove pathwise convergence to an explicit limit, as t goes to infinity, of the relative numbers of types younger than some given age and carried by a given number of individuals (small families). We also provide convergences in distribution of the sizes or ages of the largest families and of the oldest families. In the case of exponential lifetimes, population dynamics are given by linear birth and death processes, and we can most of the time provide general formulations of our results unifying both models.Comment: 20 pages, 2 figure

Educational practices and teaching techniques related to disadvantaged vocational students

The purpose of the study was to determine what educational practices and teaching techniques would be identified as significantly different when comparisons were made between teachers of programs for disadvantaged students and teachers of programs for regular students. Educational practices and teaching techniques selected for inclusion within the survey instrument were considered as representative of the teaching methods employed by secondary vocational education teachers. The sample for the study included teachers of programs for disadvantaged students and teachers of programs for regular students. Vocational service areas represented in the study were vocational agriculture, trades and industrial education, vocational office educa-tion, and vocational improvement programs. The responses of teachers were tested by analysis of variance and, when appropriate, Duncan Multiple Range Test according to classification of programs (dis-advantaged or regular), vocational service areas, years of experience in teaching disadvantaged students, and professional training in teaching disadvantaged students. Upon analysis of teacher responses it was found that within each of the tests conducted significant differences occurred. Specific findings were that teachers of programs for disadvantaged students con-sidered the following educational practices and teaching techniques less important than teachers of regular programs: work with students in out-of-school activities; use the school norm in assigning grades; require good discipline in the classroom; use role playing as a teaching technique; ask many factual questions; make use of the chalkboard, over-head projector, and slide film projector; review tests with students after grading; use models and representations in the instruction of skills; use students\u27 own experiences in class discussions; and require students to maintain a notebook. Teachers of programs for disadvantaged students considered involving students in setting the rules and regulations for the class more important than teachers of regular students. Teachers who had taken courses related to teaching disadvantaged students rated the following practices and techniques significantly higher than teachers who had not taken these courses: counsel with students; plan a course of study in consultation with other teachers; develop teaching materials supplemental to texts or other references; select remedial materials and teaching techniques; correlate mathematics, science, English, etc., with vocational subjects; and make use of visual materials. General conclusions made were: (1) diversity of vocational service areas were such that specific recommendations of educational practices and teaching techniques relative to teaching disadvantaged students should be adapted to specific service areas rather than to programs for disadvantaged students in general, (2) teachers of pro-grams for disadvantaged students were more likely to change their attitudes toward the importance of specific practices and techniques after having taught these students for one year, and (3) the effect of courses related to teaching disadvantaged students resulted in a greater dif-ference between the responses of teachers than the effect of conferences and seminars related to teaching disadvantaged students

Hindu-Muslim Riots

This study includes a history of the patterns and background of the long sequence between Hindus and Muslims in India. The riots are discussed in terms of the geographic locations where they were most prevalent, the times when they were most frequent, and the structure of the mob violence once it occurs. The method utilized is reconstruction of as many past riots as possible, together with data collected on major riots witnessed by the author during his field research upon this subject in India and Pakistan. For this purpose, a detailed schedule was constructed. The various sources for finding data upon social violence in India are discussed and their relative merits for different types of information are weighed. In addition to a chapter on methodology, the work includes the division of social violence into categories on the basis of the location of political power in respect to the warring factions. The period of Muslim rule in India found a religious minority in the dominant position so that any violence against the Muslims brought strong retaliation from the state. Under the British colonial realm, a theoretically neutral third force made religious violence a combat between equals neither of whom was backed by the government. Although there is some evidence for the biased participation of British officials in communal affairs generally in an effort to “divide and rule”, in cases of the suppression of actual violence they were relatively impartial in restoring order. Gradually the indigenous population won greater participation in the government and in the struggle for the share in the power, used the weapon of religion to gain better position and used the enhanced political position in their religious quarrels. The cycle was complete when the two religions, this time upon a basis of majority control, again became identified with state power in India and Pakistan. Once again the dominated religious community was relatively helpless in the face of the onslaught of the opposite community, now a majority, and assumed to be supported by the government. The specific riots described in detail include the Muslim-Parsi riot of 1875, the Moplah Rebellion of 1921, the Kohat Riots of 1924, the Calcutta Riots of 1925, the Bombay Riots of 1929, the Dacca Riots of 1930, the Cawnpore Riots of 1931, the Dacca Riots of 1941, the Calcutta Riots of August 1946, the Noakhali Riots of October 1946, the Bihar Riots of October-November 1946, and the Punjab Riots at the time of Partition in 1947. In addition to detailed accounts of important individual riots, a chapter describes the incidents which most frequently resulted in communal clashes, and the general political and economic background. This report is part of a larger work now in preparation on a comprehensive history of Hindu-Muslim relations in India up to and including the present troubles between India and Pakistan

Preliminary Investigation into Modeling The Damage to Carbon Fibre Composites Due to the Thermo-electric Effects of a Lightning Strikes

The impact of a lightning strike causes a short high electrical current burst through Carbon Fibre Composites (CFC). Due to the electrical properties of CFC the large current leads to a rapid heating of the surrounding impact area which degrades and damages the CFC. It is therefore necessary to study in detail the thermal response and possible degradation processes caused to CFC. The degradation takes place in two ways, firstly via direct mechanical fracture due to the thermal expansion of the CFC and secondly via thermo-chemical processes (phase change and pyrolysis) at high temperatures. The main objective of this work is to construct a numerical model of the major physical processes involved, and to understand the correlation between the damage mechanisms and the damage witnessed in modern CFC. For this work we are only considering the thermo-chemical degradation of CFC. Bespoke numerical models have been constructed to predict the extent of the damage caused by the two thermo-chemical processes separately (e.g. a model for phase change and a model for pyrolysis). The numerical model predictions have then been verified experimental by decoupling of the damage mechanisms, e.g. the real Joule heating from a lightning strike is replaced by a high power laser beam acting on composite surface. This was done to simplify the physical processes which occur when a sample is damaged. The experimentally damaged samples were then investigated using X-ray tomography to determine the physical extent of the damage. The experimental results are then compared with the numerical predictions by considering the physical extent of the polymer removal. The extent of polymer removal predicted by the numerical model, solving for pyrolysis, gave a reasonable agreement with the damage seen in the experimental sample. Furthermore the numerical model predicts that the damage caused by polymer phase change has a minimal contribution to the overall extent of the damage

Measuring social structure in the past: A comparison of historical class schemes and occupational stratification scales on Dutch 19th and early 20th century data

To what degree are HISCO based measures of class (HISCLASS and SOCPO) and occupational stratification (HIS-CAM) comparable with each other and contemporary measures? Next to a large degree of congruency, we find considerable differences between the measures, raising questions concerning the comparability of occupation-based measures across studies

Kids, Toys and Fast Food: An Unhealthy Mix?

Increasingly the fast food industry is scrutinised for marketing toy premiums towards young children. Toy premiums are claimed to lure young children to consume unhealthy meal offerings, pester parents, encourage materialism and ultimately lead to a rise in childhood obesity. Numerous studies have commented on the use of toy premiums as a marketing technique, but little research has been conducted on the actual effectiveness of toy premiums targeted to children on consumer purchase behaviour at the point of purchase. This study, investigates the use of a child targeted toy premium (Snoopy) by a fast food company (McDonald’s), and its effect in the buyers’ purchases

The Emergence of WealthTech: An Opportunity for Islamic Banking?

The paper explores disruptive innovation in the wealth and asset management arena where a new intelligent digital ecosystem is reinventing the rules. The manuscript sheds light on the evolution of the financial sector and expounds on the development of financial technologies, with special attention paid to the various conceptual models related to wealth and asset management. The models describe the Fintech and WealthTech arenas as complex adaptive systems. Authors also investigate the mindset by which WealthTech ventures create, deliver, and capture value—whether such value is economic, social, cultural, or of any other form. Online wealth management was studied via case studies. The conclusion explores the researcher’s agenda on WealthTech.

Using pivots to explore heterogeneous collections: A case study in musicology

In order to provide a better e-research environment for musicologists, the musicSpace project has partnered with musicology’s leading data publishers, aggregated and enriched their data, and developed a richly featured exploratory search interface to access the combined dataset. There have been several significant challenges to developing this service, and intensive collaboration between musicologists (the domain experts) and computer scientists (who developed the enabling technologies) was required. One challenge was the actual aggregation of the data itself, as this was supplied adhering to a wide variety of different schemas and vocabularies. Although the domain experts expended much time and effort in analysing commonalities in the data, as data sources of increasing complexity were added earlier decisions regarding the design of the aggregated schema, particularly decisions made with reference to simpler data sources, were often revisited to take account of unanticipated metadata types. Additionally, in many domains a single source may be considered to be definitive for certain types of information. In musicology, this is essentially the case with the “works lists” of composers’ musical compositions given in Grove Music Online (http://www.oxfordmusiconline.com/public/book/omo_gmo), and so for musicSpace, we have mapped all sources to the works lists from Grove for the purposes of exploration, specifically to exploit the accuracy of its metadata in respect to dates of publication, catalogue numbers, and so on. Therefore, rather than mapping all fields from Grove to a central model, it would be far quicker (in terms of development time) to create a system to “pull-in” data from other sources that are mapped directly to the Grove works lists

Integrating musicology's heterogeneous data sources for better exploration

Musicologists have to consult an extraordinarily heterogeneous body of primary and secondary sources during all stages of their research. Many of these sources are now available online, but the historical dispersal of material across libraries and archives has now been replaced by segregation of data and metadata into a plethora of online repositories. This segregation hinders the intelligent manipulation of metadata, and means that extracting large tranches of basic factual information or running multi-part search queries is still enormously and needlessly time consuming. To counter this barrier to research, the “musicSpace” project is experimenting with integrating access to many of musicology’s leading data sources via a modern faceted browsing interface that utilises Semantic Web and Web2.0 technologies such as RDF and AJAX. This will make previously intractable search queries tractable, enable musicologists to use their time more efficiently, and aid the discovery of potentially significant information that users did not think to look for. This paper outlines our work to date

musicSpace: integrating musicology's heterogeneous data sources

A significant barrier to the research endeavours of musicologists (and humanities scholars more generally) is the sheer amount of potentially relevant information that has accumulated over centuries. Whereas researchers once faced the daunting prospect of physically scouring through endless primary and secondary sources in order to answer the basic whats, wheres and whens of history, these sources and the data they contain are now increasingly available online. Yet the vast increase in the online availability of data, the heterogeneity of this data, the plethora of data providers, and, moreover, the inability of current search tools to manipulate metadata in useful and intelligent ways, means that extracting large tranches of basic factual information or running multi-part search queries is still enormously and needlessly time consuming. Accordingly, the musicSpace project is exploiting Semantic Web technologies (Berners-Lee et al., 2001) to develop a search interface that integrates access to musicology’s largest and most significant online resources. This will make previously intractable search queries tractable, thus allowing our users to spend their research time more efficiently and ultimately aiding the attainment of new knowledge. This brief paper gives an overview of our work