Multinational location decisions and the impact on labour markets

Foreign direct investment (FDI) has grown far more rapidly than trade during the last two decades. As with the other prominent features of globalisation, FDI is controversial. The impact of FDI on labour markets has been of growing concern, particularly, for source countries. The deterioration of labour market conditions for unskilled workers in many OECD countries during the 1980s and 1990s was a primary catalyst for the concern. As for its impact on labour markets, FDI may have effects that, at least in the short- and medium-run, may well dwarf the effects of trade and immigration. In this paper, we present a simple partial equilibrium model that focusses on the location decisions of multinational firms. We use the model to analyse the effects of higher labour standards, a race-to-the-bottom and capital market integration

Current transformers transient response modelling using electromagnetic transient program (EMTP)

The subject of this thesis is Current Transformer Transient response study using an electromagnetic Transient program (EMTP). Current transformers are considered eyes for power system protection. Behaviours of protection systems depend largely on information fed to them by instrument transformers. Ferromagnetic current transformers have for many years provided practical method of current measurement, however there are limitations associated with current transformer operation:- notably, difficult in maintaining accuracy over the full range of operating conditions, and most particularly current transformers tendency to suffer saturation of iron core during severe faults, with accompanying severe ratio or loss of output. These limitations might lead to mal operation of protective relays due to distorted inputs from current transformers particularly in transient periods. This thesis involved studying the behaviour of current transformers in both steady state and transient periods. An emphasis being put on transient periods which are very crucial in behaviour of current transformers because transformation errors are greatest in these periods. Errors in current transformer transformation might affect operation of entire protection schemes. Maloperation of current transformers in transient periods have very bad effect on relay co-ordination and worst condition might be failure of protection scheme operation altogether. Over the past decades engineers have been trying to develop a current transformer model that would represent a current transformer well in transient periods. It has proved to be rather difficult to come up with a single detailed model that would satisfy all possible conditions. This is due to non-linearity of magnetising curve and saturation effects of current transformer iron cores. The author has considered different current transformer models with their merits and demerits being highlighted. It has been shown that different current transformer models have to be used when considering different operating conditions of a current transformer in a power system. ATP-EMTP an Electromagnetic Transient Program was developed in the sixties for the study of electromagnetic transients in power systems. It has proved to be a very useful tool in this regard. The program development is still going on today to accommodate a wide application in power systems. Several components have been developed to represent different components in a power system. It is only recently that there has been a growing interest to include modelling of protective equipment. This has been accelerated by the inclusion of MODELS in the EMTP program. This thesis explores the effect of transients taking into account different conditions like transient fault currents, effects of high frequency waves and surges. Effects of different types of burdens on current transformers were explored as well. Due to limitations of EMTP, simulation results are only applicable to current transformers with ARMCO M4 oriented steel with ungapped cores. The author arrived at several conclusions. The most important conclusion is that mal operation of protective relays due to current transformer saturation can be avoided easily if proper current transformer selection is given priority in power protection design. EMTP package proved to be very useful and handy when studying transients though one has to be careful with numerical oscillations which might be present during simulations. Problems of numerical oscillations have been discussed under current transformer simulation tools

Multinational location decisions and the impact on labour markets

Foreign direct investment (FDI) has grown far more rapidly than trade during the last two decades. As with the other prominent features of globalisation, FDI is controversial. The impact of FDI on labour markets has been of growing concern, particularly, for source countries. The deterioration of labour market conditions for unskilled workers in many OECD countries during the 1980’s and 1990’s was a primary catalyst for the concern. As for its impact on labour markets, FDI may have effects that, at least in the short- and medium-run, may well dwarf the effects of trade and immigration. In this paper, we present a simple partial equilibrium model that focusses on the location decisions of multinational firms. We use the model to analyse the effects of higher labour standards, a ‘race-to-the-bottom’ and capital market integration

Design and simulation of vehicle controllers through genetic algorithms

Genetic Programming (GP) is a population-based evolutionary technique, which, unlike a Genetic Algorithm (GA) does not work on a fixed-length data structure, but on a variable-length structure and aims to evolve functions, models or programs, rather than finding a set of parameters. There are different histories of driver development, so different proposals of the use of PG to evolve driver structures are presented. In the case of an autonomous vehicle, the development of a steering controller is complex in the sense that it is a non-linear system, and the control actions are very limited by the maximum angle allowed by the steering wheels. This paper presents the development of an autonomous vehicle controller with Ackermann steering evolved by means of Genetic Programming

Rangewide Population Structure of the Clearnose Skate

Skates (family Rajidae) are benthic elasmobranchs that are highly vulnerable to incidental fishery bycatch, are dis-carded at sea, and are poorly accounted for in catch records. Many aspects of skate life history, such as population structure, are not well understood. Without this knowledge, indiscriminate removal may have deleterious effects on scientific, conservation, and management efforts. The Clearnose Skate Rostroraja eglanteriais seasonally migratory and widely distributed in the coastal waters of the eastern United States and in the northeastern Gulf of Mexico. This study used molecular techniques to assess the population structure of Clearnose Skate for use as a biological reference point for further research and management. Specimens were collected from 2014 to 2019 byfisheries-independent surveys. High-throughput genotyping-by-sequencing was used to identify single nucleotide polymorphisms, resulting in two data sets: one consisting of 8,914 loci (outlier and neutral) and the other comprised of 30 outlier loci. Results from all analyses and using both data sets indicated a high level of genetic differentiation between specimens from the Gulf of Mexico and specimens from the U.S East Coast. Using the outlier data set, a low but significant level of genetic differentiation was also found among specimens from the U.S. East Coast, with a subtle break near the North Carolina and South Carolina border. Genetic differences along the U.S. East Coast were spatially autocorrelated,indicating a latitudinal genetic gradient. The level of observed genetic differentiation between the Gulf of Mexico and the U.S. East Coast is likely due to physical barriers such as Florida and the Gulf Stream current, while the subtle structure along the U.S. East Coast is likely attributable to isolation caused by dispersal limitations and local temperature preferences. The results from this investigation of Clearnose Skate population structure can be used to better monitor and manage this vulnerable elasmobranch

Search for optimal routes on roads applying metaheuristic algorithms

The design of efficient routes for vehicles visiting a significant number of destinations is a critical factor for the competitiveness of many companies. The design of such routes is known as the vehicle routing problem. Indeed, efficient vehicle routing is one of the most studied problems in the areas of logistics and combinatorial optimization. The present study presents a memetic algorithm that evolves using a mechanism inspired by virus mutations. Additionally, the algorithm uses Taboo Search as an intensification mechanism

Unsupervised learning algorithms applied to grouping problems

One of the tasks of great interest within process mining is the discovery of business process models, which consists of using an event log as input and producing a business process model by analyzing the data contained in the log and applying a process mining method, task and/or technique. The discovery allows the identification of the behaviors contained in the cases of the event log in order to detect possible deviations and/or validate that the business process is executed according to the business requirements. This paper presents an approach based on unsupervised learning techniques for the grouping of traces to generate simpler and more understandable models. The algorithms implemented for clustering are K-means, hierarchical agglomerative and density-based spatial clustering of applications with noise (DBSCAN)

The Control and Safety Analysis of a Small Fission Surface Power Reactor

The NKUA1 is a Small Fission Surface Power (SFSP) space reactor intended for use in upcoming missions to Mars and the moon between the years 2020-2030. The concept of the reactor was created by Dr. Lee Mason and his research team in a joint effort between the Department of Energy (DOE) and the National Aeronautics and Space Administration (NASA); complete design of the reactor core was developed by Dr. David Poston at Los Alamos National Laboratories. The Monte Carlo Neutron-Particle (MCNP) Transport code script of the NKUA1 core was used to perform a variety of criticality safety related calculations. The analysis was conducted to compare the effectiveness of control rods versus control drums in providing a safe shutdown configuration. The control drums proved to be more efficient in delivery of negative reactivity, conserved more space than the control rods, and have been found to be highly effective in space reactors. A safety analysis was also performed on the NKUA1 concerning its function in specific accident scenarios. In each accident scenario, the reflector and control drums were removed and the reactor was enclosed in a common naturally occurring material. The reactor was found to be safely shut down in each scenario, with acceptable shutdown margins being greater than $10.00