Оптимизация энергопотребления электроплавильных печей с использованием технологий предварительного подогрева шихты

Материалы ХI Международной науч.-техн. конф. студентов, магистрантов и аспирантов [28-29 апреля 2011 г., г. Гомель]. - Гомель, 2011

Speed Choice : The Driver, the Road and Speed Limits

Speed choice is one of the more characteristic features of driver behaviour. The speed a driver chooses to travel at determines the degree of difficulty he or she operates under. Higher speeds lead to more accidents, higher accident risk and more severe consequences of an accident. The present thesis examines factors that are associated with drivers’ speed choice. Repeated measures of drivers’ speed showed a reasonably high correlation, but also that stability in speed varied with road layout between measurement sites. Effects of police enforcement were studied on roads with temporary reduced speed limits (from 50 km/h to 30 km/h) during school hours. Lower speeds were found on roads with enforcement and drivers observed on one such road showed a higher perceived probability of detection than did drivers observed on a non-enforced road. However, in a laboratory study higher driving speeds and lower accident risk was associated with enforced roads. Drivers not informed about existing speed limits overestimated the limits to a large extent and chose driving speeds above the limit as did drivers informed about the limits. In an on-the-road survey, fast drivers reported higher driving speed, thought a higher percentage of other drivers were speeding and had a more positive attitude towards speeding than did slower drivers. The results suggest that drivers’ travel speed is influenced by road factors, other road users and enforcement. Furthermore, drivers’ own judgements of what is an appropriate speed are also important for speed choice

Tick-borne encephalitis : prognosis, immunization and virus strain characterization

The aims were to investigate the morbidity associated with tick-borne encephalitis (TBE) both in the acute phase and at long-term follow-up, to develop a rapid neutralization test for confirmation of TBEV-specific antibody response and to study the serological response after TBE-vaccination and, finally, to characterize Swedish human TBEV isolates. The morbidity was studied in one retrospective follow-up study of consecutive TBE-patients, treated during a 10-year period (Paper 1) and in one prospective study of TBE-patients with aseptic meningoencephalitis of non- TBE etiology as a reference group (Paper II). The retrospective study with applied neuropsychiatric questionnaire comprised 114/143 individuals followed for 47 months (20-133 months). Two elderly men were dead due to TBE. Of the remaining 112 individuals 40 (36%) were left with residual TBE related symptoms, in 31 classified as moderate or severe. The most common complaints were cognitive/neuropsychiatric symptoms, balance/coordination disturbances, headache and hearing loss/tinnitus. Three patients had permanent paralysis. A vast majority of the TBE patients had contracted the infection during leisure time and were permanent residents or visited endemic regions on regular basis. Half of them were aware of other TBE-cases in their environment. The prospective follow-up study in 85/108 TBE-patients and 64/488 non-TBE patients confirmed the existence of a post-encephalitic syndrome after TBE. 40% of TBE patients and 20% of the non-TBE patients (p=0.006) were left with residual symptoms after one year e.g. various cognitive dysfunctions, ataxia/tremor, dysphasia and headache. Nine TBE patients developed paresis, of which 5 cases persisted after one year (tetraparesis and bilateral shoulder paresis). The TBE patients had longer hospitalization-time and sick-leave, more intense blood- CSF-barrier damage and more pronounced intrathecal IgG-production compared to patients in the reference group. No CSF parameter was found useful as a prognostic marker. A rapid neutralization test (RFFIT) was developed and found sensitive and specific for confirmation of TBEVspecific antibody response (Paper III). The assay had high performance stability and took just one day to perform, in contrast to PRNT which was unstable and time-consuming. The test is useful in seroprevalence studies for confirmation of TBE-specific activity in ELISA reactive samples, for evaluation of TBE immunity and for the diagnosis of TBE patients previously exposed to other flaviviruses. The RFFIT with a Swedish human TBEV-isolate proved to be more sensitive than ELISA or HI to measure the antibody response to TBE-vaccination (FSME-ImmunTM Inject, Baxter) in 535 randomly selected adult persons (Paper IV). The emphasis of the study was laid on long-term follow-up from the 3rd until 3 years after the 5th, dose. At the time of the 3rd dose, 77% of the vaccinees had neutralizing antibody activity and at the time of the 4th-6th doses in 89-95%. The corresponding figures after the 3rd dose was >90%, and after doses 4 and 5 >98%. Based on our data and previous experience of vaccine failures after two doses, a more condensed three-dose primary vaccination schedule may be advantageous. Judging from antibody persistence, it seems justified to initiate studies of antibody persistence after the 4th dose for periods beyond the recommended three- year booster interval. Swedish TBEV strains have previously not been characterized. 17 human strains were studied, isolated from acute phase serum of TBE patients, three from 1958-1966 and 14 from 1991-1994 (Paper V). Serological characterization using a panel of E-specific mouse MAbs and cross-neutralization indicated that the strains belonged to the Western TBEV subtype which includes the Austrian vaccine strain Neudoerfl. Genetic analysis of a partial E-sequence confirmed the close relationship: all Swedish strains belonged to the Western TBEV lineage. When comparing the almost complete sequence of the E-gene of two Swedish strains with the Neudoerfl strain only one conservative amino acid substitution was found. This close similarity and the neutralizing activity to a local strain evoked by the vaccine indicate that the vaccine available in Sweden ought to induce a proper protection. A correlation between the phylogenetic relationships and the geographical origin of the strains was indicated, but genetic data or geographic origin did not correlate to severity of disease

Investing in the Future: The Performance of Green Bonds Compared to Conventional Bonds and Stocks

As the world faces unprecedented environmental challenges, there is an urgent need for largescale investments in green infrastructure and technologies. If we are going to achieve carbon neutrality, significant investments are necessary, and therefore must the entire financial system unite and endorse sustainable investment activities in a market-oriented manner.   A green bond is a relatively new type of bond. It was first introduced in 2007 by the European Investment Bank (EIB). This was followed up by a collaboration between Skandinaviska Enskilda Banken (SEB) and the World Bank, a group of Swedish investors, pension funds, and SRI-focused investors. They issued their first green bond in 2008 intending to attract more investors. However, this attempt to increase the interest did not work, green bonds were almost nonexistent until 2013. One explanation for the slow development of the green bond market was the financial crisis in 2008. Further, the reason for the low interest in green bonds during this period was that traditional investors deemed these risky and non-profitable.  Using a deductive approach, this thesis investigates how green bonds perform compared to conventional bonds and stocks from the issuing company. The authors sampled green and conventional bonds from 33 companies that matured from 2018 to 2023. The sample data set contains bonds from Asia, Europe, South America, North America, and Australia. The data was tested using multiple hypotheses.  This thesis sets out to answer the research question: How do green bonds perform compared to conventional bonds and stocks?   The results indicated there is a significant difference between the three asset types. First, the stocks yield higher returns and higher standard deviations than green and conventional bonds. Second, the authors found no evidence for a difference in return thus a significant difference in standard deviation. The results also suggest there is a difference in modified duration, convexity, maturity, and yield to maturity. These findings indicate that green bonds performed better than conventional bonds, especially regarding risk and volatility. Therefore, could green bonds be useful when diversifying a portfolio.  The findings suggested that a portfolio composition that combines the three assets could be in line with both shareholder theory and stakeholder theory. The portfolio theory also provides interesting insights into the potential portfolio optimizations since there are differences between green and conventional bonds. Since no difference in the return was found for green and conventional bonds the authors find no reason to support the idea of herding behavior in the trading of green bonds.  However, the difference in standard deviation is interesting from a behavioral perspective, a lower standard deviation indicates that the green bond experiences lower volatility compared to conventional bonds.

Organizing construction logistics outsourcing : a logistics strategy perspective

Purpose The construction industry shows an increased interest in how to manage logistics within construction projects. Often construction logistics is outsourced to a logistics service provider (LSP). However, construction logistics is normally approached either as a strategic decision or as an operational issue and rarely as a tactical concern. The purpose of this study is to explore how to organize the logistics outsourcing decision at strategic, tactical and operational levels. Design/methodology/approach This study is performed as a single-case study within a construction corporation, containing (amongst others) a building contractor (BC) and a construction equipment rental company (CERC) offering logistics services. Findings The study shows that to procure construction logistics service successfully, BCs need logistics capabilities at strategic and tactical levels to maintain an alignment between the use of logistics services and operational characteristics. Simultaneously, CERC’s need to design their service offerings to correspond to the needs of the BC. Research limitations/implications This study builds on a single-case study of a Swedish construction corporation. Further research is needed to better understand current logistics outsourcing and development practices and how these can be improved to foster better logistics management at the project level. Practical implications BCs find suggestions of different logistics organization structures and suitable outsourcing arrangements. CERCs and LSPs can use the findings to understand their customers’ needs and adapt service offerings. Originality/value To the best of the authors’ knowledge, this study is one of the first studies of how two companies within a corporation can work together to develop construction logistics service offerings.Funding: Development Fund of the Swedish Construction Industry (SBUF) [13843]; Lars Erik Lundberg Foundation for Research and Education</p

Investing in the Future: The Performance of Green Bonds Compared to Conventional Bonds and Stocks

As the world faces unprecedented environmental challenges, there is an urgent need for largescale investments in green infrastructure and technologies. If we are going to achieve carbon neutrality, significant investments are necessary, and therefore must the entire financial system unite and endorse sustainable investment activities in a market-oriented manner.   A green bond is a relatively new type of bond. It was first introduced in 2007 by the European Investment Bank (EIB). This was followed up by a collaboration between Skandinaviska Enskilda Banken (SEB) and the World Bank, a group of Swedish investors, pension funds, and SRI-focused investors. They issued their first green bond in 2008 intending to attract more investors. However, this attempt to increase the interest did not work, green bonds were almost nonexistent until 2013. One explanation for the slow development of the green bond market was the financial crisis in 2008. Further, the reason for the low interest in green bonds during this period was that traditional investors deemed these risky and non-profitable.  Using a deductive approach, this thesis investigates how green bonds perform compared to conventional bonds and stocks from the issuing company. The authors sampled green and conventional bonds from 33 companies that matured from 2018 to 2023. The sample data set contains bonds from Asia, Europe, South America, North America, and Australia. The data was tested using multiple hypotheses.  This thesis sets out to answer the research question: How do green bonds perform compared to conventional bonds and stocks?   The results indicated there is a significant difference between the three asset types. First, the stocks yield higher returns and higher standard deviations than green and conventional bonds. Second, the authors found no evidence for a difference in return thus a significant difference in standard deviation. The results also suggest there is a difference in modified duration, convexity, maturity, and yield to maturity. These findings indicate that green bonds performed better than conventional bonds, especially regarding risk and volatility. Therefore, could green bonds be useful when diversifying a portfolio.  The findings suggested that a portfolio composition that combines the three assets could be in line with both shareholder theory and stakeholder theory. The portfolio theory also provides interesting insights into the potential portfolio optimizations since there are differences between green and conventional bonds. Since no difference in the return was found for green and conventional bonds the authors find no reason to support the idea of herding behavior in the trading of green bonds.  However, the difference in standard deviation is interesting from a behavioral perspective, a lower standard deviation indicates that the green bond experiences lower volatility compared to conventional bonds.

Kärnkraftsdebatt ger möjlighet till kritiskt tänkande i högstadiefysiken

I skolans styrdokument betonas vikten av att elever ges möjlighet att utveckla sitt kritiska tänkande. Detta är inte minst angeläget i dessa tider av tillgång till sociala medier och spridande av så kallade alternativa fakta. Trots sin positiva klang finns det dock ingen etablerad konsensus kring vad kritiskt tänkande egentligen är. Inom ramen för ett skolutvecklingsprojekt i samverkan mellan Uppsala universitet och Tiundaskolan, en 4-9-skola i Uppsala, utforskar vi hur kritiskt tänkande kan uttryckas i undervisningspraktiken i ämnena svenska, historia, matematik och fysik. Som exempel har vi i fysikämnet designat, genomfört och analyserat en undervisningssekvens utifrån kärnkraft som tema, där elever i årskurs 9 gavs möjlighet att anamma olika åsikter och argument i frågan genom rollspel. Eleverna genomförde en debatt, där de representerade olika parter: boende nära Forsmark, miljöorganisationen Grön Fred, och företag som utvecklar kärnkraft, respektive vindkraft. Före och efter debatten skrev eleverna individuella texter där de argumenterade för sin personliga åsikt i frågan: Ska kärnkraften bevaras som den är, läggas ner, eller utvecklas? Vi fann att de genom debatten fick goda möjligheter att utveckla och visa kunskaper motsvarande flera kunskapskrav i kursplanen i fysik som annars sällan berörs i fysikklassrummet, såsom, för betyg A: ”Eleven kan samtala om och diskutera frågor som rör energi, teknik, miljö och samhälle och skiljer då fakta från värderingar och formulerar ställningstaganden med välutvecklade motiveringar samt beskriver några tänkbara konsekvenser.” Som exempel på naturvetenskapligt förankrade argument utnyttjade eleverna genererad energi per utsläppt mängd koldioxid som ett mått vid jämförelser mellan kärnkraft och andra energikällor. I de individuella texterna höll de flesta eleverna fast vid sina åsikter från innan de arbetade med temat även efteråt, men nu med fler och mer nyanserade argument

Dioxiner : ett särskilt problem för Bottenhavet

Halterna av dioxiner i biota minskade från 1970-talet och framåt. Från 1980-talet har dockförbättringen avstannat. Speciellt allvarlig är situationen i Bottenhavet, där halterna i exempelvisströmming är särskilt höga. Det krävs nu snabba och adekvata åtgärder om vi även i framtidenska kunna äta strömming och lax från Östersjön.2002BOTTNISKA VIKEN sid 34-37</p