175 research outputs found
Does leverage affect labour productivity? A comparative study of local and multinational companies of the Baltic countries
This paper investigates the impact of leverage on labour productivity of companies operating in the Baltic countries, with a focus on differences between local and multinational companies. We employ a fixed effects regression model on company level data, covering the period from 2001 to 2008. Our results demonstrate that the impact of leverage on labour productivity is non-linear and it differs dramatically between local and multinational companies. In the case of local companies, at low levels of leverage, an increase in external financing tends to bring along an improvement in labour productivity, while at higher levels of leverage an increase in debt financing appears to result in a loss of labour productivity. For multinational companies, the impact of leverage on labour productivity tends to be more linear and leverage appears to have a negative impact on labour productivity. Although debt overhang is believed to be an issue in the Baltic countries in general, local companies with low leverage might be able to increase labour productivity by additional borrowing.
First published online: 19 Oct 201
Regeneration of former industrial areas – a case study of the former meat factory property in Tartu
Käesolevas töös käsitletakse pruunalade tekkimist, kahjulikke mõjusid ning taasarenduse
takistusi ja lahendusi. Töö eesmärk on kirjeldada endiste tööstusalade taasarendamise barjääre
Teguri 43 (Tartu endise lihakombinaadi) näitel. Uurimustöö koostamiseks viidi läbi
intervjuud arendajaga, linnavalitsusega ning kolme huvitatud maaomanikuga uuritavast
sadamaraudtee, Teguri ja Tähe tänava vaheliselt alalt. Lisaks kasutati Tartu Linnavalitsuse
linnaplaneerimise osakonna arhiivi materjale, et koostada uurimisalast ajalooline ülevaade.
Intervjuudest ilmnes, et endise lihakombinaadi ala taasarendus sõltub erinevatest takistustest,
mistõttu ala on siiani arendamata. Barjäärid on omavahel sõltuvad ning keerukad, kuid nende
lahendamine on erinevate osapoolte koostööl võimalik. Eesti pruunalade käsitlemist
arengukavades ja planeeringutes on vähe. Pruunalade teadvustamine ning nende planeerimise
lihtsustamine muudaks sellised alad atraktiivsemaks arendustegevuseks.
Uurimustöö on kasulik edaspidistele uurimustele ning probleemi teadvustamisele Eestis.
Pakutud on ka lahendusi pruunalade probleemi paremaks käsitlemiseks, tuues näiteid riikides
kasutatud praktikast. Antud töö aitab kaasa pruunala mõiste levikule, et selle ametlikuks
kasutuseks viidaks läbi asjakohaseid uuringuid.This reasearch focuses on brownfield related problems such as creation of brownfields, its
negative impacts on environment, redevelopment barriers and possible solutions. The purpose
of the research is to identify brownfield development barriers appeared in Tartu’s former meat
factory area. For the purpose of the reasearch interviews were held with the developer, Tartu
City Government and three land owners from the area between harbour railway, Teguri and
Tähe street. Also data from Land Survey and Use archival were collected to compile a
historical review of the area.
The analysis of the interviews show that the redevelopement case of the former meat factory
area has many barriers. That is the reason, why the researched area is still undeveloped. The
barriers are complex and interconnected, but still possible to solve through cooperation of
different parties. Brownfield issue is poorly covered in Estonian planning and development
program documents. To make brownfields more attractive for redevelopement, the planning
regulations should be simplified.
The result of this thesis can be used for future studies and to spread the awareness of
brownfield issue in Estonia. There are also solutions used in other countries practises to
improve handling the brownfield problem. This reasearch contributes to spreading the term
brownfield, so that appropriate researches will be made to take this to official us
Tehisnärvivõrkude rakendatavuse hindamine FouKG signaali töötlemiseks
http://www.ester.ee/record=b4688662*es
Graphene functionalised by laser ablated V2O5 as highly sensitive NH3 sensor
Graphene has been recognized as a promising gas sensing material. The
response of graphene-based sensors can be radically improved by introducing
defects in graphene using, e. g., metal or metal oxide nanoparticles. We have
functionalised CVD grown, single layer graphene by applying pulsed laser
deposition (PLD) of V2O5 which resulted in a thin V2O5 layer on graphene with
average thickness of ~0.6 nm. According to Raman analysis, PLD process also
induced defects in graphene. Compared to unmodified graphene, the obtained
chemiresistive sensor showed considerable improvement of sensing ammonia at
room temperature. In addition, also the response time, sensitivity and
reversibility were essentially enhanced due to graphene functionalisation by
laser deposited V2O5. This can be explained by increased surface density of gas
adsorption sites introduced by high energy atoms in laser ablation plasma and
formation of nanophase boundaries between deposited V2O5 and graphene.Comment: 22 pages, 6 figure
Semiquantitative Classification of Two Oxidizing Gases with Graphene-Based Gas Sensors
Miniature and low-power gas sensing elements are urgently needed for a portable electronic nose, especially for outdoor pollution monitoring. Hereby we prepared chemiresistive sensors based on wide-area graphene (grown by chemical vapor deposition) placed on Si/Si3N4 substrates with interdigitated electrodes and built-in microheaters. Graphene of each sensor was individually functionalized with ultrathin oxide coating (CuO-MnO2, In2O3 or Sc2O3) by pulsed laser deposition. Over the course of 72 h, the heated sensors were exposed to randomly generated concentration cycles of 30 ppb NO2, 30 ppb O3, 60 ppb NO2, 60 ppb O3 and 30 ppb NO2 + 30 ppb O3 in synthetic air (21% O2, 50% relative humidity). While O3 completely dominated the response of sensors with CuO-MnO2 coating, the other sensors had comparable sensitivity to NO2 as well. Various response features (amplitude, response rate, and recovery rate) were considered as machine learning inputs. Using just the response amplitudes of two complementary sensors allowed us to distinguish these five gas environments with an accuracy of ~ 85%. Misclassification was mostly due to an overlap in the case of the 30 ppb O3, and 30 ppb O3 + 30 ppb NO2 responses, and was largely caused by the temporal drift of these responses. The addition of recovery rates to machine learning input variables enabled us to very clearly distinguish different gases and increase the overall accuracy to ~94%
Structure-Dependent CO 2
Rare earth oxycarbonates are potential candidate materials for constructing simple and low-cost chemiresistive sensors for monitoring carbon dioxide (CO2) gas in the living and working environment for personal comfort and health reasons. Also, measurement of CO2 concentrations is needed in many industrial processes. Specifically, sol-gel made nanoparticles of Nd and La oxycarbonates have been studied previously as novel CO2 gas sensor materials. In this paper, pulsed laser deposition of La oxycarbonate (La2O2CO3) thin films was studied and structural properties of obtained thin films were characterized. Also, CO2 gas sensing ability of synthesized films was evaluated. The films deposited under CO2 partial pressure in various conditions were all Raman amorphous. In situ or ex situ annealing procedure at high CO2 partial pressure was needed for obtaining crystalline La2O2CO3 films, whereby hexagonal and monoclinic polymorphs were obtained in ex situ and in situ processes, respectively. Sensor structure, made using in situ process, was sensitive to CO2 gas and showed relatively fast response and recovery characteristics
MTDATA and the prediction of phase equilibria in oxide systems : 30 years of industrial collaboration
This paper gives an introduction to MTDATA, Phase Equilibrium Software from the National Physical Laboratory (NPL), and describes the latest advances in the development of a comprehensive database of thermodynamic parameters to underpin calculations of phase equilibria in large oxide, sulfide, and fluoride systems of industrial interest. The database, MTOX, has been developed over a period of thirty years based upon modeling work at NPL and funded by industrial partners in a project co-ordinated by Mineral Industry Research Organisation. Applications drawn from the fields of modern copper scrap smelting, high-temperature behavior of basic oxygen steelmaking slags, flash smelting of nickel, electric furnace smelting of ilmenite, and production of pure TiO2via a low-temperature molten salt route are discussed along with calculations to assess the impact of impurities on the uncertainty of fixed points used to realize the SI unit of temperature, the kelvin
Towards Increased Recovery of Critical Raw Materials from WEEE– evaluation of CRMs at a component level and pre-processing methods for interface optimisation with recovery processes
Increasing recovery of critical raw materials (CRMs) from waste electrical and electronic equipment (WEEE) is a strategic priority to mitigate supply risks. Today, CRM recovery rates are generally low, with increases requiring new recovery processes and interface optimisation with pre-processing to ensure appropriate material flows for efficient recovery are generated. Here, results from an industrial trial to increase CRM recovery from WEEE are presented to inform development of pre-processing strategies which generate such material flows. Au, Ag, Co, Ga, Mg, Nb, Ru, Pd, Ir, Y, Nd, Sb, Ta and W are identified with XRF in components of a range of WEEE samples including within individual printed circuit board (PCB) components. CRM distribution in PCBs is mapped by visual inspection with reference to this data. Cost-effective methods to disassemble WEEE; isolate CRM bearing components, and upgrade/concentrate CRMs are evaluated for industrial adoption. A guillotine is found most suitable for LCD disassembly and separation of Au edge-contacts from PCBs, while cryocracking is best for isolation of internal components of digital media devices. Thermal PCB disassembly with a solder bath for simultaneous SMD removal and subsequent sieving to sort SMDs thereby concentrating CRMs for recovery is a promising approach. Microwave ashing of PCBs to concentrate CRMs is promising although off-gas treatment would be required. Recovery potential of identified CRMs from material streams generated is found to be poor due to lack of suitable recovery infrastructure except for precious and platinum group metals in PCBs, but available pyrometallurgical recovery permanently dissipates other CRMs present
MTDATA and the Prediction of Phase Equilibria in Oxide Systems: 30 Years of Industrial Collaboration
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