On the Infrared Limit of Two Dimensional QCD

We study the infrared limit of two dimensional QCD, with massless dynamical Dirac fermions that are in the fundamental representation of the gauge group. We find that the theory reduces to a spin generalization of the Calogero model with an additional magnetic coupling which is of the Pauli type.Comment: 9 pages, UU-ITP 29/93, HU-TFT-93-6

On quantum cohomology and dynamical systems

We investigate aspects of quantum cohomology and Floer cohomology in the context of a generic classical Hamiltonian system. In particular, we show that Floer's instanton equation is related to a quantum Euler character in the quantum cohomology defined by topological nonlinear \sigma-model. This relation is an infinite dimensional analogy with the relation between Poincar\'e-Hopf and Gauss-Bonnet-Chern formulae in classical Morse theory. By applying localization techniques to functional integrals we then show that for a K\"ahler manifold this quantum Euler character also coincides with the Euler character determined by the deRham cohomology of the target space. Our results are consistent with the Arnold conjecture which estimates periodic solutions to classical Hamilton's equations in terms of deRham cohomology of the phase space

Change management as a part of successful ICT project management

This study focuses on studying the importance of change management within ICT project management. The topic is viewed from a project manager’s point of view and the study provides a general overview of ICT project management and the most common challenges in it. A model for ICT project management is created by using the existing literature and interview data. A general picture on change management and ICT project management was created by using various sources of secondary data. Empirical data was gathered by individual interviews from a single case company. The company has conducted several ICT projects during the past years but does not operate in ICT business. The purpose of the interviews was to gain a picture how ICT projects are managed in practice and whether change management practices can be seen in the management. An ICT project must have three key factors in place in order to have chances for success. The factors are: communication, a competent project manager with project experience and knowledge about the organization’s core business, and top management support. Change management is an important part of the general project management but it is not enough alone if the project manager is otherwise not competent enough or other key factors for a successful project are not in place. Change management practices must support the project management without forgetting the basics of practical day-to-day project management

Exploring the Co-operative Form’s Potential in Crowdfunding : A Non-monetary Perspective

Technology-driven change has generated new, even revolutionary business models, characterized by high levels of user participation. In the finance field, business models based on crowdfunding have seen significant growth and entered use as an alternative means of extending access and gaining financing for various types of projects. Nonetheless, current crowdfunding practices have been subject to criticism for issues such as information asymmetry, lack of trust and transaction costs, spurring discussion of how to develop and improve these practices. One way of speaking to the criticism has been a suggestion that platforms could be owned by the ones who use them. While the associated way of thinking, referred to as platform co-operativism, has seen some inroads in practice, its novel and practical nature means that a clear knowledge gap remains with regard to its potential for dealing with challenges of platform economy. Consequently, the aim of this study is to examine the relevance and potential of the co-operative company form for crowdfunding arrangements. Our conceptual study utilizes existing research on co-operatives and considers features of crowdfunding from three different perspectives: asymmetry of information and of trust, interaction frequency and homogeneity of interests. As a result, we provide three taxonomies for outlining future research on co-operative platforms.Technology-driven change has generated new, even revolutionary business models, characterized by high levels of user participation. In the finance field, business models based on crowdfunding have seen significant growth and entered use as an alternative means of extending access and gaining financing for various types of projects. Nonetheless, current crowdfunding practices have been subject to criticism for issues such as information asymmetry, lack of trust and transaction costs, spurring discussion of how to develop and improve these practices. One way of speaking to the criticism has been a suggestion that platforms could be owned by the ones who use them. While the associated way of thinking, referred to as platform co-operativism, has seen some inroads in practice, its novel and practical nature means that a clear knowledge gap remains with regard to its potential for dealing with challenges of platform economy. Consequently, the aim of this study is to examine the relevance and potential of the co-operative company form for crowdfunding arrangements. Our conceptual study utilizes existing research on co-operatives and considers features of crowdfunding from three different perspectives: asymmetry of information and of trust, interaction frequency and homogeneity of interests. As a result, we provide three taxonomies for outlining future research on co-operative platforms.Peer reviewe

Management of water balance in mining areas – WaterSmart : Final Report

Although mining companies have long been conscious of water related risks, they still face environmental management challenges. Several recent environmental incidents in Finnish mines have raised questions regarding mine site environmental and water management practices. This has increased public awareness of mining threats to the environment and resulted in stricter permits and longer permitting procedures. Water balance modelling aids in predictive water management and reduces risks caused by an excess or shortage of water at a mining site. In this study the primary objective was to exploit online water quantity and water quality measurements to better serve water balance management. The second objective was to develop and test mathematical models to calculate the water balance in mining operations. The third objective was to determine how monitoring and modelling tools can be integrated into the management system and process control. According to the experience gained from monitoring water balances, the main recommendation is that the data should be stored in a database where it is easily available for water balance calculations. For real-time simulations, online measurements should be available from strategically defined positions in the mine site. Groundwater may also act as a source or sink with respect to mine site surface water, and therefore monitoring and investigations should be designed to account for the full water balance. In Finland it is possible to calculate water balance for planning or for operative purposes by using the Watershed Simulation and Forecasting System (WSFS) developed at the Finnish Environment Institute (SYKE). This system covers every sub-basin (10-50 km2) over the whole of Finland. WSFS automatically obtains the latest observations of temperature, precipitation, water level, discharge and other needed data provided by the Finnish Meteorological Institute (FMI), SYKE, as well as other sources. The system also uses these observations to follow-up on simulation and forecasting accuracy. The water balance model was further developed to simulate and forecast the water balance at the Yara Siilinjärvi mine site. The WSFS-model was also extended with one-way coupling to the groundwater flow model. The model is operated via a web-based user interface and can produce water-balance forecasts automatically, if necessary, several times a day. The water balance and water flow in the area are simulated using real-time weather observations. The model enables forecasting water levels and planning discharges and pumping at the mine site. Possible uses of the model include preparation for spring floods by emptying ponds for storage of water from snow melt, estimation of the effect of heavy rainfall and calculating the required outflow from the mine site reservoir. Thus, overflows and dam-breaks can be avoided and consequently prevent the leakage of contaminated water. Furthermore, as the model can be modified to simulate changes at the mine site, it can also be beneficial during the mine site-planning process. The water balance model is currently operational for Yara Siilinjärvi mine site and hydrological forecasts are produced on a daily basis. Water level, discharge and pumping data, essential for modelling the area, are provided by the mine operator and EHP-Tekniikka Ltd. The model uses meteorological observations and forecasts from FMI as inputs for the simulations and forecasts. In addition to the accurate weather forecasts, the real time observations are a key factor in the accuracy of the model forecasts. GoldSim is the most popular commercial simulation software solution chosen, not only by mines worldwide, but also in many other sectors. One of the main reasons for its extensive use is its versatility and the ability to expand the program as the needs of the mine require. As the mine project progresses, one of GoldSim’s strongest assets is risk analysis at different phases during both the planning and execution of mine operations. The use of the GoldSim platform was tested during the project and some new features were developed. The project has paid special attention to commercialization of the developed products and well thought out policies for possible joint bids

Topological Sigma-model, Hamiltonian Dynamics and Loop Space Lefschetz Number

We use path integral methods and topological quantum field theory techniques to investigate a generic classical Hamiltonian system. In particular, we show that Floer's instanton equation is related to a functional Euler character in the quantum cohomology defined by the topological nonlinear $\sigma$--model. This relation is an infinite dimensional analog of the relation between Poincar\'e--Hopf and Gauss--Bonnet--Chern formul\ae$~$ in classical Morse theory, and can also be viewed as a loop space generalization of the Lefschetz fixed point theorem. By applying localization techniques to path integrals we then show that for a K\"ahler manifold our functional Euler character coincides with the Euler character determined by the finite dimensional de Rham cohomology of the phase space. Our results are consistent with the Arnold conjecture which estimates periodic solutions to classical Hamilton's equations in terms of de Rham cohomology of the phase space.Comment: 10 pages, LaTEX. New title and some modifications in the text. Version to appear in Phys. Lett.

Monitoring of water content in a porous reservoir by seismic data: A 3D simulation study

A potential framework to estimate the amount of water stored in a porous storage reservoir from seismic data is neural networks. In this study, the water storage reservoir system is modeled as a coupled poroviscoelastic-viscoelastic medium, and the underlying wave propagation problem is solved using a three-dimensional discontinuous Galerkin method coupled with an Adams-Bashforth time stepping scheme. The wave problem solver is used to generate databases for the neural network-based machine learning model to estimate the water content. In the numerical examples, we investigate a deconvolution-based approach to normalize the effect from the source wavelet in addition to the network's tolerance for noise levels. We also apply the SHapley Additive exPlanations method to obtain greater insight into which part of the input data contributes the most to the water content estimation. The numerical results demonstrate the capacity of the fully connected neural network to estimate the amount of water stored in the porous storage reservoir

New insights into the chemical activation of lignins and tannins using K₂CO₃—a combined thermoanalytical and structural study

Engineering of activated carbons (ACs) through chemical activation of organic precursors has been extensively studied for a wide variety of biopolymers, biomasses, wastes and other fossil-based precursors. Despite huge efforts to engineer evermore performant and sustainable ACs, “searching-for-the-best-recipe” type of studies are more the rule than the exception in the published literature. Emerging AC applications related to energy and gas storage require strict control of the AC properties and a better understanding of the fundamentals underlying their engineering. In this study, we provide new insights into the K2CO3 chemical activation of plant-based polyphenols—lignins and tannins—through careful thermoanalytical and structural analyses. We showed for the the first time that the reactivity of polyphenols during K2CO3 chemical activation depends remarkably on their purity and structural properties, such as their content of inorganics, OH functionalities and average molecular weight. We also found that the burn-off level is proportional to the K2CO3/lignin impregnation ratio (IR), but only within a certain range—high impregnation ratios are not needed, unlike often reported in the literature. Furthermore, we showed for the first time that the K2CO3 chemical activation of different carbon surfaces from lignins and tannins can be modelled using simple global solid-state decomposition kinetics. The identified activation energies lay in the range of values reported for heterogenous gas-carbon surface gasification reactions (O2-C, H2O-C, or CO2-C) in which the decomposition of C(O) surface complexes is the common rate-limiting step.</p

Comparison of the Growth and Thermal Properties of Nonwoven Polymers after Atomic Layer Deposition and Vapor Phase Infiltration

The growth mechanism of Atomic Layer Deposition (ALD) on polymeric surfaces differs from growth on inorganic solid substrates, such as silicon wafer or glass. In this paper, we report the growth experiments of Al2O3 and ZnO on nonwoven poly-L-lactic acid (PLLA), polyethersulphone (PES) and cellulose acetate (CA) fibres. Material growth in both ALD and infiltration mode was studied. The structures were examined with a scanning electron microscope (SEM), scanning transmission electron microscope (STEM), attenuated total reflectance-fourier-transform infrared spectroscopy (ATR-FTIR) and 27Al nuclear magnetic resonance (NMR). Furthermore, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis were used to explore the effect of ALD deposition on the thermal properties of the CA polymer. According to the SEM, STEM and ATR-FTIR analysis, the growth of Al2O3 was more uniform than ZnO on each of the polymers studied. In addition, according to ATR-FTIR spectroscopy, the infiltration resulted in interactions between the polymers and the ALD precursors. Thermal analysis (TGA/DSC) revealed a slower depolymerization process and better thermal resistance upon heating both in ALD-coated and infiltrated fibres, more pronounced on the latter type of structures, as seen from smaller endothermic peaks on TA

Comparison of the Growth and Thermal Properties of Nonwoven Polymers after Atomic Layer Deposition and Vapor Phase Infiltration

The growth mechanism of Atomic Layer Deposition (ALD) on polymeric surfaces differs from growth on inorganic solid substrates, such as silicon wafer or glass. In this paper, we report the growth experiments of Al2O3 and ZnO on nonwoven poly-L-lactic acid (PLLA), polyethersulphone (PES) and cellulose acetate (CA) fibres. Material growth in both ALD and infiltration mode was studied. The structures were examined with a scanning electron microscope (SEM), scanning transmission electron microscope (STEM), attenuated total reflectance-fourier-transform infrared spectroscopy (ATR-FTIR) and 27Al nuclear magnetic resonance (NMR). Furthermore, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis were used to explore the effect of ALD deposition on the thermal properties of the CA polymer. According to the SEM, STEM and ATR-FTIR analysis, the growth of Al2O3 was more uniform than ZnO on each of the polymers studied. In addition, according to ATR-FTIR spectroscopy, the infiltration resulted in interactions between the polymers and the ALD precursors. Thermal analysis (TGA/DSC) revealed a slower depolymerization process and better thermal resistance upon heating both in ALD-coated and infiltrated fibres, more pronounced on the latter type of structures, as seen from smaller endothermic peaks on TA