Analytical investigation of the atmospheric radiation limits in semigray atmospheres in radiative equilibrium

We model the wavelength-dependent absorption of atmospheric gases by assuming constant mass absorption coefficients in finite-width spectral bands. Such a semigray atmosphere is analytically solved by a discrete ordinate method. The general solution is analyzed for a water vapor saturated atmosphere that also contains a carbon dioxide-like absorbing gas in the infrared. A multiple stable equilibrium with a relative upper limit in the outgoing long-wave radiation is found. Differing from previous radiative–convective models, we find that the amount of carbon dioxide strongly modifies the value of this relative upper limit. This result is also obtained in a gray (i.e., equal absorption of radiation at all infrared wavelengths) water vapor saturated atmosphere. The destabilizing effect of carbon dioxide implies that massive carbon dioxide atmospheres are more likely to reach a runaway greenhouse state than thin carbon dioxide ones

Switching components for medium voltage drives

Nowadays power drives are the essential part almost of all technological processes. Improvement of efficiency and reduction of losses require development of semiconductor switches. It has a particular meaning for the constantly growing market of renewable sources, especially for wind turbines, which demand more powerful semiconductor devices for control with growth of power. Also at present semiconductor switches are the key component in energy transmission, optimization of generation and network connection. The aim of this thesis is to make a survey of contemporary semiconductor components, showing difference in structures, advantages, disadvantages and most suitable applications. There is topical information about voltage, frequency and current limits of different switches. Study tries to compare dimensions and price of different components. Main manufacturers of semiconductor components are presented with the review of devices produced by them, and a conclusion about their availability was made. IGBT is selected as a main component in this study, because nowadays it is the most attractive component for usage in power drives, especially at the low levels of medium voltage. History of development of IGBT structure, static and dynamic characteristics are considered. Thesis tells about assemblies and connection of components and problems which can appear. One of key questions about semiconductor materials and their future development was considered. For the purpose of comparison strong and weak sides of different switches, calculation of losses of IGBT and its basic competitor – IGCT is presented. This master’s thesis makes an effort to answer the question if there are at present possibilities of accurate selection of switches for electrical drives of different rates of power and looks at future possible ways of development of semiconductor market.

Strike hard, strike sure - Operation Musketeer : British military planning during the Suez Crisis, 1956

Operation Musketeer, a combined joint Anglo-French operation aimed at regaining control of the Suez Canal in 1956, has received much attention from scholars. The most common approach to the crisis has been to examine the political dimension. The political events that led Prime Minister Anthony Eden’s cabinet to decide to use military force against the wishes of their superior American ally and in the face of American economic pressure and a Soviet threat to attack Paris and London with rockets have been analysed thoroughly. This is particularly the case because the ceasefire and eventual withdrawal were an indisputable defeat of British policy in the Middle East. The military operation not only ruined Prime Minister Eden’s career, but it also diminished the prestige of Britain. It was the beginning of the end, some claim. The British Empire would never be the same. As the consequences of using force are generally considered more important than the military operations themselves, very little attention has been paid to the military planning of Operation Musketeer. The difference between the number of publications on Operation Corporate of the Falklands War and Operation Musketeer is striking. Not only has there been little previous research on the military aspects of Musketeer, the conclusions drawn in the existing works have not reached a consensus. Some historians, such as Correlli Barnett, compare Musketeer to the utter failures of the Tudor landings and Gallipoli. Among significant politicians, Winston Churchill, who had retired from the prime ministership only a year before the Suez Crisis, described the operation as “the most ill-conceived and ill-executed imaginable”. Colin McInnes, a well-known author on British defence policy, represents the middle view when he describes the execution as “far from failure”. Finally, some, like Julian Thompson, the Commander of 3 Commando Brigade during the Falklands War, rate the military action itself as being successful. The interpretation of how successful the handling of the Suez Crisis was from the military point of view depends very much on the approach taken and the areas emphasised in the subject. Frequently, military operations are analysed in isolation from other events. The action of a country’s armed forces is separated from the wider context and evaluated without a solid point of comparison. Political consequences are often used as validated criteria, and complicated factors contributing to military performance are ignored. The lack of comprehensive research on the military action has left room for an analysis concentrating on the military side of the crisis.

Limits of Meritocracy. How Fields of Study and Gender Segregation Affect Social Stratification in Finland

This dissertation critically reviews the idea of meritocracy from both a theoretical and an empirical perspective. Based on a discussion of classical texts of social philosophy and sociology, it is argued that meritocracy as a concept for social stratification is best compatible with the sociological tradition of status attainment research: both frame social inequality in primarily individualistic terms, centring on the role of ascribed (e.g., gender, social background) and achieved (e.g., educational qualifications) characteristics for determining individuals’ socioeconomic rewards. This theoretical argument introduces the research problem at the core of this dissertation: to what extent can the individualistic conception of social stratification be maintained empirically? Fields of study and their interaction with educational attainment levels play a prominent role in the analysis of this question. Drawing on sociological versions of segmented labour market theory, it is assumed that fields of study may channel individuals into heterogeneous political-economic contexts on the labour market, which potentially modify the socioeconomic benefit individuals derive from their qualification levels. The focus on fields of study may also highlight economic differentials between men and women that derive from the persisting segregation of men’s and women’s occupational and educational specializations rather than direct gender discrimination on the labour market. The quantitative analyses in this dissertation consist of three research articles, which are based primarily on Finnish data, but occasionally extend the view to other European countries. The data sources include register-based macro- and microdata as well as survey data. Article I examines the extent and the patterns of gender segregation within the Finnish educational system between 1981 and 2005. The results show that differences between men’s and women’s field specializations have for the most part remained stable during this period, with particularly high levels of gender segregation observed at lower educational levels. The focus in Article II rests on the effects of gender-segregated fields of study on higher education graduates’ occupational status. It is shown that fields of study matter for accessing professional jobs and avoiding low-skilled positions in Finland: at the early career stage, particularly polytechnic graduates from female-dominated fields are less likely to work in professional positions. Finnish university graduates from male-dominated fields were more likely than their peers with different specializations to work as professionals, yet they also faced a greater risk of being sorted into lowskilled jobs if they failed to make use of this advantage. Article III proceeded to analyse the joint impact of educational qualification levels and fields of study on young adults’ median earnings in Finland between 1985 and 2005. The results show that qualification levels do not confer a consistent benefit in the process of earnings stratification. Advanced qualifications raise median earnings most clearly among individuals specializing in the same field of study. When comparing individuals with different field specializations, on the other hand, higher-level qualifications do not necessarily lead to higher median earnings. Overall, the findings of this dissertation reveal a heterogeneous effect of education for achieving social positions, which challenges individual-centred, meritocratic accounts of social stratification and underlines the problematic lack of structural and institutional dimensions in the dominant account of social status attainment.

Carrier selection and management : A case study on Neste Oil Retail

Service provider selection has been said to be a critical factor in the formation of supply chains. Through successful selection companies can attain competitive advantage, cost savings and more flexible operations. Service provider management is the next crucial step in outsourcing process after the selection has been made. Without proper management companies cannot be sure about the level of service they have bought and they may suffer from service provider's opportunistic behavior. In worst case scenario the buyer company may end up in locked-in situation in which it is totally dependent of the service provider. This thesis studies how the case company conducts its carrier selection process along with the criteria related to it. A model for the final selection is also provided. In addition, case company's carrier management procedures are reflected against recommendations from previous researches. The research was conducted as a qualitative case study on the principal company, Neste Oil Retail. A literature review was made on outsourcing, service provider selection and service provider management. On the basis of the literature review, this thesis ended up recommending Analytic hierarchy process as the preferred model for the carrier selection. Furthermore, Agency theory was seen to be a functional framework for carrier management in this study. Empirical part of this thesis was conducted in the case company by interviewing the key persons in the selection process, making observations and going through documentations related to the subject. According to the results from the study, both carrier selection process as well as carrier management were closely in line with suggestions from literature review. Analytic hierarchy process results revealed that the case company considers service quality as the most important criteria with financial situation and price of service following behind with almost identical weights with each other. Equipment and personnel was seen as the least important selection criterion. Regarding carrier management, the study resulted in the conclusion that the company should consider engaging more in carrier development and working towards beneficial and effective relationships. Otherwise, no major changes were recommended for the case company processes.

Stability Analysis in Multicriteria Discrete Portfolio Optimization.

Almost every problem of design, planning and management in the technical and organizational systems has several conflicting goals or interests. Nowadays, multicriteria decision models represent a rapidly developing area of operation research. While solving practical optimization problems, it is necessary to take into account various kinds of uncertainty due to lack of data, inadequacy of mathematical models to real-time processes, calculation errors, etc. In practice, this uncertainty usually leads to undesirable outcomes where the solutions are very sensitive to any changes in the input parameters. An example is the investment managing. Stability analysis of multicriteria discrete optimization problems investigates how the found solutions behave in response to changes in the initial data (input parameters). This thesis is devoted to the stability analysis in the problem of selecting investment project portfolios, which are optimized by considering different types of risk and efficiency of the investment projects. The stability analysis is carried out in two approaches: qualitative and quantitative. The qualitative approach describes the behavior of solutions in conditions with small perturbations in the initial data. The stability of solutions is defined in terms of existence a neighborhood in the initial data space. Any perturbed problem from this neighborhood has stability with respect to the set of efficient solutions of the initial problem. The other approach in the stability analysis studies quantitative measures such as stability radius. This approach gives information about the limits of perturbations in the input parameters, which do not lead to changes in the set of efficient solutions. In present thesis several results were obtained including attainable bounds for the stability radii of Pareto optimal and lexicographically optimal portfolios of the investment problem with Savage's, Wald's criteria and criteria of extreme optimism. In addition, special classes of the problem when the stability radii are expressed by the formulae were indicated. Investigations were completed using different combinations of Chebyshev's, Manhattan and Hölder's metrics, which allowed monitoring input parameters perturbations differently.

Auringon asemaa seuraavan aurinkopaneelijärjestelmän kehittäminen

Tässä diplomityössä käsitellään Aurinkoa seuraavan aurinkopaneelijärjestelmän kehittämistä Suomen olosuhteisiin. Työ on tehty osana Lappeenrannan teknillisen yliopiston Green Campus-projektia, jossa tarkoituksena on tuottaa yliopistolle energiaa uusiutuvilla menetelmillä ja käyttää niitä apuna tutkimuksessa sekä opetuksessa. Tavoitteena työssä on ymmärtää Auringon seuraamisen hyödyt sekä mahdolliset haitat aurinkopaneeli sovellutuksissa. Aikaisemman tutkimustiedon ollessa vähäistä, on työssä pyritty löytämään laskentamalli tuottavuuden laskentaan riippumatta siitä, missä päin maapalloa aurinkopaneelijärjestelmä sijaitsee. Työ alkaa kirjallisuustutkimuksella, jossa käydään läpi aurinkopaneelien toimintaperiaate, aurinkoenergian ja auringonpaistetuntien suuruusluokat Suomessa, sekä Suomen sääoloista johtuvat vaatimukset aurinkopaneelijärjestelmille. Tämän jälkeen on vertailtu kaupallisia järjestelmiä. Lopuksi järjestelmällistä tuotesuunnittelua hyväksikäyttäen suunnitellaan oma versio Aurinkoa seuraavasta aurinkopaneelijärjestelmästä. Oman suunnitelman järkevyyttä simuloidaan pienoismallilla Matlab-Arduino ympäristössä ja pyritään löytämään mahdollisia heikkouksia. Suomessa aurinkoenergiasta 90 % saadaan maalis – syyskuun aikana. Nykyisillä akkujärjestelmillä aurinkoenergia Suomessa ei sovellu kuin täydentäväksi energianlähteeksi. Aurinkoa seuraamalla voidaan saavuttaa 25-30 % tuottavuuden lisäys kesäaikana verrattuna staattiseen järjestelmään. Talvella hyöty tippuu 0-10 % luokkaan. Pienoismallilla simuloidut ohjaustavat osoittivat, että Aurinkoa on mahdollista seurata ilman sensoreita laskemalla Auringon paikka tähtitieteen kaavoista.

Relationship between Brazilian airline pilot errors and time of day

Flight safety is one of the most important and frequently discussed issues in aviation. Recent accident inquiries have raised questions as to how the work of flight crews is organized and the extent to which these conditions may have been contributing factors to accidents. Fatigue is based on physiologic limitations, which are reflected in performance deficits. The purpose of the present study was to provide an analysis of the periods of the day in which pilots working for a commercial airline presented major errors. Errors made by 515 captains and 472 copilots were analyzed using data from flight operation quality assurance systems. To analyze the times of day (shifts) during which incidents occurred, we divided the light-dark cycle (24:00) in four periods: morning, afternoon, night, and early morning. The differences of risk during the day were reported as the ratio of morning to afternoon, morning to night and morning to early morning error rates. For the purposes of this research, level 3 events alone were taken into account, since these were the most serious in which company operational limits were exceeded or when established procedures were not followed. According to airline flight schedules, 35% of flights take place in the morning period, 32% in the afternoon, 26% at night, and 7% in the early morning. Data showed that the risk of errors increased by almost 50% in the early morning relative to the morning period (ratio of 1:1.46). For the period of the afternoon, the ratio was 1:1.04 and for the night a ratio of 1:1.05 was found. These results showed that the period of the early morning represented a greater risk of attention problems and fatigue.

Näkökulmia 3D-tulostuksen opetukseen ja koulutukseen

Additive manufacturing, or 3D printing, is globally one of most interesting area in developing of manufacturing technologies. This technology is suitable for fabrication off industrial products and it interests actors in fields of computer sciences, economics, medical sciences and design&arts. Additive manufacturing is often referred as third industrial revolution: first revolution was invention of steam engines in 18th century and second was industrial revolution started by Henry Ford in 1920s. Companies should be able to test suitability of their products for additive manufacturing and 3D printing but also how much better products could be when products are totally re-designed so that all potential of this new technology can be utilized. This is where education has its importance; new generations who enter working life should be educated to know of additive manufacturing and 3D printing, its advantages but also of it limits. There has to be also possibility to educate industry and people already working there, so that industrial implementation could be done successfully. This is especially very valid for Finland. Education is strongly needed so that Finnish industry can maintain its competence in global markets. Role of education is extremely important when a new technology is industrially implemented. Additive manufacturing and 3D printing offers freedom to design new products, production and generally ways of doing things. Development, planning and execution of education for additive manufacturing and 3D printing is challenging as this area develops very fast. New innovations are coming almost every month. Planning of education for additive manufacturing and 3D printing requires collection pieces of data from various of sources. Additive manufacturing and 3D printing industry and its development has to be followed frequently, and material for additive manufacturing and 3D printing has to be renewed frequently.

Charles Larned letter, April 3, 1813.

Charles Larned (1791-1834) was a lawyer and American military officer who served during the War of 1812. He was the son of Simon Larned (1753-1817), who served as a captain in the Revolutionary War and was a member of the United States Congress from Massachusetts from 1804-1805. Charles studied law in the office of Henry Clay in Kentucky, and was dining with a group of prominent citizens when word was received that General William Henry Harrison could soon be overpowered by General Henry Proctor. Colonel Owen, a member of the group, organized a regiment to reinforce Harrison’s troops. Larned became a member and subsequently survived the River Raisin Massacre and was later present at the Battle of the Thames. He was also part of a group of men who learned of General William Hull’s plan to surrender Detroit to the British and planned to overtake him should this occur. However, the plan failed, Hull did surrender and the men became prisoners of the British. After the war, Larned became a lawyer, and served as Attorney General of Michigan Territory during the Black Hawk War. During the cholera epidemic of 1834, he worked tirelessly to assist others, but was stricken with the disease and died. Letter Transcription: Pittsfield, April 8, 1813 I think that by this time my dear Charles you will allow I have some reason to give you a gentle reprimand for breach of duty—but I will not censure you upon suspicion maybe you have substantial reasons—at any rate one cannot very graciously reproach the other for negligence I for one am healthy as ham & that we have so seldom exchanged letters during your absence & on my honor promise to be a better girl in future—but the truth is my Dear Charles I am secretary for the Family—Mama you know never writes & James but seldom & they are all dispersed in different directions, consequently I have many calls upon my time—this to be sure is a pleasant duty & I urge it only as a slight palliation for my remissness if you should consider it as such—now I have finished my preface—I will try to be more interesting & doubtless I succeed. Our dear Father we hope & trust is now in Green Bush, where he will probably remain a month perhaps & from thence he expects to go to Sacket’s harbor—at which place you know our troops are fast collecting-- We shall hope to see him either here or there before he goes. Brother George I believe is [still] at Plattsburgh but expects soon to be removed to some other military part perhaps with Papa (I hope so at least). We have just got letters from Brothers Sylvester & Joseph at Middlebury—they are in good health. Mama has for some weeks been afflicted with an inflammation in her eyes but seems now to be convalescing. Sister Martha has been somewhat unwell for a few weeks but is now tolerably recovered. James & myself are both in our usual good health & at this time seated by the same stand, one reading, the other writing. Thus my Dear Charles have I given you an abstract history of our Family—but here indeed is a wonderful omission; not a word about Miss Harriet Hunt, who in truth ought to have been noted first but the last she’s not the least in my memory. She is much grown since you saw her, but does not speak as fluently as we could wish—a few word she can say. Probably before this you have been informed of the great loss your friend Sherrill has sustained in the death of his mother—also of the revolution that has taken place in Hackbridge as it respects the religion & morality of the place that more than one hundred on the plain have become religious converts & c—indeed I am at a loss what to say that will afford your pleasure—a narrative at this time must be gloomy indeed. The distressing situation of our country at this time would make almost any recital melancholy. The prevailing epidemic has swept off many of your acquaintance no doubt. Mrs. Dewey of Williamstown, the sister of Mrs. Danforth, has left a Husband, Children & many Friends sincerely to lament her loss—some few have died in our village, but we have escaped astonishingly –it has raged in every town about us--If we are unwilling to acknowledge a God in his mercies. I fear she shall be compelled to do it in the awfulness of his judgments.--------I am much [pleased] with our new neighbors the Parsons Wife & a Miss Woodward her cousin is a fine girl, I think, Mrs. Allen has not a handsome face but something in her manner that interests one her person I think the handsomest I ever saw & the Parson seems well pleased with his selection—Mrs. Ripley is with them this winter & will probably remain thro the summer—Her husband at [Sackett’s Harbor] little or no alteration is apparent since her marriage—she seems as gay & fond of company as ever.-------Mrs. [McKnight] it is expected will commence housekeeping in about three weeks in the house formerly occupied by Mr…. [Report] says that Mr. Goodman & Clarissa Weller are soon to be married & many other things that I must omit to mention for Mama wants a… PS reserved--now my Dear Charles remember you are considerably… & I am confident you have as much leisure as I have –… be ceremonious but write whenever I find time not & I beg… the same – I tell James I shall not send his love for he must write himself. I shall anxiously expect you to write & do not disappoint your affectionate, sister--H One word my Dear Charles from your affectionate Mother who longs to see Her Dear son Charles—but being deprived of that rich blessing at present—begs Him so to conduct that she may hope for it ere long—do you search the Scriptures and keep the Sabbath holy unto the Lord—and all the sacred Commandments of God—it is my ardent desire…He would protect, support and provide for your soul and body and believe me your affectionate friend and Mother. R Larned.

Charles Larned letter - April 3, 1813

Letter Transcription: Pittsfield, April 8, 1813 I think that by this time my dear Charles you will allow I have some reason to give you a gentle reprimand for breach of duty—but I will not censure you upon suspicion maybe you have substantial reasons—at any rate one cannot very graciously reproach the other for negligence I for one am healthy as ham & that we have so seldom exchanged letters during your absence & on my honor promise to be a better girl in future—but the truth is my Dear Charles I am secretary for the Family—Mama you know never writes & James but seldom & they are all dispersed in different directions, consequently I have many calls upon my time—this to be sure is a pleasant duty & I urge it only as a slight palliation for my remissness if you should consider it as such—now I have finished my preface—I will try to be more interesting & doubtless I succeed. Our dear Father we hope & trust is now in Green Bush, where he will probably remain a month perhaps & from thence he expects to go to Sacket’s harbor—at which place you know our troops are fast collecting-- We shall hope to see him either here or there before he goes. Brother George I believe is [still] at Plattsburgh but expects soon to be removed to some other military part perhaps with Papa (I hope so at least). We have just got letters from Brothers Sylvester & Joseph at Middlebury—they are in good health. Mama has for some weeks been afflicted with an inflammation in her eyes but seems now to be convalescing. Sister Martha has been somewhat unwell for a few weeks but is now tolerably recovered. James & myself are both in our usual good health & at this time seated by the same stand, one reading, the other writing. Thus my Dear Charles have I given you an abstract history of our Family—but here indeed is a wonderful omission; not a word about Miss Harriet Hunt, who in truth ought to have been noted first but the last she’s not the least in my memory. She is much grown since you saw her, but does not speak as fluently as we could wish—a few word she can say. Probably before this you have been informed of the great loss your friend Sherrill has sustained in the death of his mother—also of the revolution that has taken place in Hackbridge as it respects the religion & morality of the place that more than one hundred on the plain have become religious converts & c—indeed I am at a loss what to say that will afford your pleasure—a narrative at this time must be gloomy indeed. The distressing situation of our country at this time would make almost any recital melancholy. The prevailing epidemic has swept off many of your acquaintance no doubt. Mrs. Dewey of Williamstown, the sister of Mrs. Danforth, has left a Husband, Children & many Friends sincerely to lament her loss—some few have died in our village, but we have escaped astonishingly –it has raged in every town about us--If we are unwilling to acknowledge a God in his mercies. I fear she shall be compelled to do it in the awfulness of his judgments.--------I am much [pleased] with our new neighbors the Parsons Wife & a Miss Woodward her cousin is a fine girl, I think, Mrs. Allen has not a handsome face but something in her manner that interests one her person I think the handsomest I ever saw & the Parson seems well pleased with his selection—Mrs. Ripley is with them this winter & will probably remain thro the summer—Her husband at [Sackett’s Harbor] little or no alteration is apparent since her marriage—she seems as gay & fond of company as ever.-------Mrs. [McKnight] it is expected will commence housekeeping in about three weeks in the house formerly occupied by Mr…. [Report] says that Mr. Goodman & Clarissa Weller are soon to be married & many other things that I must omit to mention for Mama wants a… PS reserved--now my Dear Charles remember you are considerably… & I am confident you have as much leisure as I have –… be ceremonious but write whenever I find time not & I beg… the same – I tell James I shall not send his love for he must write himself. I shall anxiously expect you to write & do not disappoint your affectionate, sister--H One word my Dear Charles from your affectionate Mother who longs to see Her Dear son Charles—but being deprived of that rich blessing at present— begs Him so to conduct that she may hope for it ere long—do you search the Scriptures and keep the Sabbath holy unto the Lord—and all the sacred Commandments of God—it is my ardent desire…He would protect, support and provide for your soul and body and believe me your affectionate friend and Mother. R Larned.

On Limits to the Use of Linear Markov Strategies in Common Property Natural Resource Games

We derive conditions that must be satisfied by the primitives of the problem in order for an equilibrium in linear Markov strategies to exist in some common property natural resource differential games. These conditions impose restrictions on the admissible form of the natural growth function, given a benefit function, or on the admissible form of the benefit function, given a natural growth function.

Certification of community-based forest enterprises (CFEs): limits of the Brazilian experiences

The Brazilian Amazon is one of the world’s largest tropical forests. It supplies more than 80 % of Brazil’s timber production and makes this nation the second largest producer of tropical wood. The forestry sector is of major importance in terms of economic production and employment creation. However, the Brazilian Amazon is also known for its high deforestation rate and for its rather unsustainably managed timber resources, a fact which puts in the balance the long-term future of the forestry sector in the region. Since the mid- 1990s, with strong support from World Wildlife Fund (WWF), the number of tropical forests certified by the Forest Stewardship Council (FSC) has significantly increased. This is especially true for projects sponsored by large scale companies. The number of community- based forest management projects has also increased. Certification of community-based forest enterprises (CFEs) was initially a goal for the sponsors and community members. Certification is viewed as a way to reach alternative timber markets. In Brazil, the state of Acre has the highest concentration of CFEs certified by FSC. Most of them have been implemented with the support of environmental NGOs and public funds. Environmental NGOs strongly defend the advantages of certification for communities; however, in reality, this option is not that advantageous. Despite all the efforts, the number of participants in each project remains low. Why is this occurring? In this paper, we analyze the underlying motives of a few individual’s participation in CFEs certification projects. We aim to present and discuss some factors that shape the success of CFEs and their later certification. The results are based on surveys conducted in two certified CFEs in the state of Acre.