<p>In this thesis we report on calculations for open quantum mechanical and certain microwave systems. The models refer to a quantum point contact and an electron cavity. We model this open system with an imaginary potential as source and drain, and use the finite difference method to make our calculations. We report on general features of the model we have found, and compare our calculations with measurements made on microwave cavities.</p>

<p>Bakgrund: Migration är ett vanligt förekommande fenomen idag vare sig den är ofrivillig eller frivillig. Mycket forskning har gjorts om den ofrivilliga flyktingmigrationen men ytterst lite forskning har fokuserat på den frivilliga migrationen, då i synnerhet gällande högutbildade individer med special kompetens. </p><p>Avgränsningar: Vi har begränsat oss till att studera de mer rationella orsakerna till inflödet av utländsk kompetens, vilka anses vara lättare för en stat att påverka. Vidare så har vi fokuserat oss mot de individer som anses vara högutbildade eller inneha en speciell eftertraktad kompetens. Studien är också begränsad till att studera migration av högutbildad arbetskraft mellan i-länder. </p><p>Syfte: Syftet med denna uppsats är att undersöka orsakerna till det nettoinflöde av utländsk kompetens till ett visst land vilka kan påverkas av statliga åtgärder. I vårt fall har vi använt oss av Nederländerna som ett studieobjekt i vår undersökning för att se vad den nederländska staten gjort för att attrahera utländsk kompetens. Genomförande: Uppsatsen baseras på empiriska resultat som insamlades under en veckas uppehåll i Nederländerna. Vi har också använt oss av litteratur och artiklar angående migration av högutbildade. Viss statistik data angående Nederländerna har också använts. </p><p>Resultat: Vi har funnit att orsakerna till migration av högutbildade individer styrs av både rationella och irrationella faktorer som mer eller mindre kan påverkas av statliga åtgärder. Vad gäller Nederländerna så har man inte tagit några åtgärder med det explicita syftet att attrahera utländsk kompetens. Detta har blivit en positiv konsekvens av den nederländska statens försök att attrahera utländska direktinvesteringar. Slutligen har vi funnit att"brain drain"inte nödvändigtvis är en negativ företeelse på lång sikt.</p> / <p>Background: It is a common phenomenon for people today to leave their country of origin to move to another country. Involuntary movements have been the focus of much research, however little has been done to explain why voluntary migration takes place specifically amongst highly skilled individuals.</p><p>Purpose: The purpose of this report is therefore to investigate the reasons for the net inflow of foreign skilled workforce to a country, which a government can influence. In doing so we have made use of the Netherlands as a case study. </p><p>Limitations: We have focused on the inflow of foreign competence for more rational reasons, which a country's government could have some influence upon. Furthermore, we will concentrate on those individuals who are considered to be highly educated or specialists. The study is limited to the migration of skilled labour from one industrialised country to another. </p><p>Manner of Proceedings: The report is based on empirical results collected during a weeks visit to the Netherlands. We have also made use of literature and articles treating the brain drain-brain gain phenomenon. Some use of statistics regarding the Netherlands has also been used. </p><p>Results: We have found that the reasons for the migration of highly skilled labour is dependent on both rational and irrational factors of influence. The possibility for a government to influence any of these issues varies. Regarding the Netherlands nothing has been done with the explicit intent of attracting foreign competence, this has been a positive side effect in the attempt to attract FDI. Finally we have found that brain drain is not necessarily a bad phenomenon in the long run.</p>

The extent of agricultural drainage has created concern for its potential undesirable effects on surface water quality. Land applications of liquid manure on tile drain fields have the potential to transport solutes and bacteria to the drains following precipitation or irrigation events and many times are directly sent to a surface water body, and have been documented as a source of contamination of surface waters. This study determined the potential for and magnitude of E. coli and solute migration to tile drains through the soil profile. Water from subsurface drains was analyzed for chemical and bacterial composition following tracer applications. Two sites were selected for the study to determine transport at large (field) and small (plot) scales. At the large-scale site, both tracers, bacteria (E. coli and Total Coliform) and Amino-G (a conservative tracer), were used to monitor the speed of transport from the surface to the tile drain following liquid manure applications, tracer applications and additionally precipitation events. The concentrations of E. coli were monitored every hour for 76 days during the spring. Both tracers, bacteria and Amino-G, were detected in the tile drainage shortly after precipitation events. The peak concentration of E. coli was observed to be 1.2 x 10⁶ CFU/l00mL. These elevated concentrations of E. coli might be attributed to the characteristics of the soil, high organic matter and well-structured clay soils. Both the rapid breakthrough of tracer to the tile drain and the peaks of tile water temperature during precipitation events provided evidence of macropore flow. Antecedent soil moisture and warmer temperatures appeared to provide ideal conditions for bacteria growth. The small-scale study site was selected for a more focused study. The purpose of this site was to quantify more accurately the percent mass of surface applied tracer that was transported to the tile drain, allowing mass balance calculations. Experiments were conducted during the summer to control the rate and total amount of irrigation. Amino-G readings were taken every 10 seconds for 125 hours of continuous irrigation. Tracer applications were conducted at runoff and non-runoff conditions. Both types of tracer applications had Amino-G breakthrough in less than 10 minutes after initiation of irrigation. Tracer applied at runoff rates resulted in 4 to 17 times more total tracer mass migrating to the tile drain than when applied at non-runoff rates. The total mass of Amino-G migrating to the tile drain during non-runoff conditions depended on the total volume of applied tracer, regardless of the tracer concentration. For an application of 5.6 mm at 12 mg/L, 5.7% of the total applied tracer migrated to the tile drain, whereas for an application of 1.9 mm at 27.7 mg/L only 2.8% of the total applied tracer migrated to the tile drain. Tile flow response to irrigation experiments appeared to be governed by soil moisture. Lysimeter samples were taken continuously every 4-8 hours until the 94th hour after tracer application. Tile water concentrations were consistently greater than concentrations found in the deeper suction lysimeters at corresponding times, providing further evidence of preferential flow. E. coli transported through the soil and into the drains were demonstrated to be event-driven by precipitation events and irrigation events. In addition, the characteristics of this type of soil - the high clay content, the well-defined structure, the high level of organic matter and rich biological activity has been known to enhance the preferential pathways and transport processes in the soil profile, resulting in rapid transport of surface applied solutes and effluents to tile drains. / Graduation date: 2003

Bakgrund: Migration är ett vanligt förekommande fenomen idag vare sig den är ofrivillig eller frivillig. Mycket forskning har gjorts om den ofrivilliga flyktingmigrationen men ytterst lite forskning har fokuserat på den frivilliga migrationen, då i synnerhet gällande högutbildade individer med special kompetens. Avgränsningar: Vi har begränsat oss till att studera de mer rationella orsakerna till inflödet av utländsk kompetens, vilka anses vara lättare för en stat att påverka. Vidare så har vi fokuserat oss mot de individer som anses vara högutbildade eller inneha en speciell eftertraktad kompetens. Studien är också begränsad till att studera migration av högutbildad arbetskraft mellan i-länder. Syfte: Syftet med denna uppsats är att undersöka orsakerna till det nettoinflöde av utländsk kompetens till ett visst land vilka kan påverkas av statliga åtgärder. I vårt fall har vi använt oss av Nederländerna som ett studieobjekt i vår undersökning för att se vad den nederländska staten gjort för att attrahera utländsk kompetens. Genomförande: Uppsatsen baseras på empiriska resultat som insamlades under en veckas uppehåll i Nederländerna. Vi har också använt oss av litteratur och artiklar angående migration av högutbildade. Viss statistik data angående Nederländerna har också använts. Resultat: Vi har funnit att orsakerna till migration av högutbildade individer styrs av både rationella och irrationella faktorer som mer eller mindre kan påverkas av statliga åtgärder. Vad gäller Nederländerna så har man inte tagit några åtgärder med det explicita syftet att attrahera utländsk kompetens. Detta har blivit en positiv konsekvens av den nederländska statens försök att attrahera utländska direktinvesteringar. Slutligen har vi funnit att"brain drain"inte nödvändigtvis är en negativ företeelse på lång sikt. / Background: It is a common phenomenon for people today to leave their country of origin to move to another country. Involuntary movements have been the focus of much research, however little has been done to explain why voluntary migration takes place specifically amongst highly skilled individuals. Purpose: The purpose of this report is therefore to investigate the reasons for the net inflow of foreign skilled workforce to a country, which a government can influence. In doing so we have made use of the Netherlands as a case study. Limitations: We have focused on the inflow of foreign competence for more rational reasons, which a country's government could have some influence upon. Furthermore, we will concentrate on those individuals who are considered to be highly educated or specialists. The study is limited to the migration of skilled labour from one industrialised country to another. Manner of Proceedings: The report is based on empirical results collected during a weeks visit to the Netherlands. We have also made use of literature and articles treating the brain drain-brain gain phenomenon. Some use of statistics regarding the Netherlands has also been used. Results: We have found that the reasons for the migration of highly skilled labour is dependent on both rational and irrational factors of influence. The possibility for a government to influence any of these issues varies. Regarding the Netherlands nothing has been done with the explicit intent of attracting foreign competence, this has been a positive side effect in the attempt to attract FDI. Finally we have found that brain drain is not necessarily a bad phenomenon in the long run.

In Canada, the non-recognition of foreign credentials remains a considerable policy issue as well as a challenge for skilled immigrants. Many studies have shed light on the difficulties that foreign professionals face when seeking a placement in the Canadian job market. This thesis focused on the experiences of professional women from Morocco on the basis of the premise that every racialized group’s immigration experience deserves a space in the literature to voice their realities and inspire policy considerations. As a result, this study focused on examining the experiences of Moroccan women in the Canadian job market and the impact thereof, on their socio-economic status, and as such, health and well-being. In order to effectively capture the experiences of this particular community, a fieldwork study was conducted in the form of semi-structured individual interviews with twelve women who immigrated to Canada from Morocco with professional qualifications. Based on the participants’ accounts, I described that systemic discrimination as manifested in Othering and racialization remain major obstacles to the realization of equal access in the Canadian labour market. All in all, this research provides valuable insight into the plight of skilled immigrants in Canada and thus, offers strong policy recommendations to facilitate a more effective integration process for this group into the Canadian Job market.

In this thesis we report on calculations for open quantum mechanical and certain microwave systems. The models refer to a quantum point contact and an electron cavity. We model this open system with an imaginary potential as source and drain, and use the finite difference method to make our calculations. We report on general features of the model we have found, and compare our calculations with measurements made on microwave cavities.

In Canada, the non-recognition of foreign credentials remains a considerable policy issue as well as a challenge for skilled immigrants. Many studies have shed light on the difficulties that foreign professionals face when seeking a placement in the Canadian job market. This thesis focused on the experiences of professional women from Morocco on the basis of the premise that every racialized group’s immigration experience deserves a space in the literature to voice their realities and inspire policy considerations. As a result, this study focused on examining the experiences of Moroccan women in the Canadian job market and the impact thereof, on their socio-economic status, and as such, health and well-being. In order to effectively capture the experiences of this particular community, a fieldwork study was conducted in the form of semi-structured individual interviews with twelve women who immigrated to Canada from Morocco with professional qualifications. Based on the participants’ accounts, I described that systemic discrimination as manifested in Othering and racialization remain major obstacles to the realization of equal access in the Canadian labour market. All in all, this research provides valuable insight into the plight of skilled immigrants in Canada and thus, offers strong policy recommendations to facilitate a more effective integration process for this group into the Canadian Job market.

Abstract Permeable reactive barrier technology is a cost effective means of treating near surface groundwater contaminant plumes. However, current reactive barrier technology lacks the capacity to manipulate flow rates and thus hydraulic retention time (HRT) within the barriers in order to maximize the effectiveness and longevity of the media. This study examines the effectiveness of tile drains as passive controls on the flow rate of ground-water through an existing wood particle media permeable reactive barrier treating agricultural nitrate. The use of upgradient and downgradient tile drains allowed HRT to be increased from 4.5 to 10 days in one trial and then to be decreased from 11.1 to 0.8 days in a second trial. Influent groundwater NO3-N concentrations of ~100 mg/L were attenuated to detection limit (0.02 mg/L) only 12% of the 4 m long barrier with HRTs of 4.5 to 10 days. During the second trial, HRT was decreased to 0.8 days and NO3-N penetrated to the downgradient edge of the PRB at 1.8 mg/L. The behaviour of SO4 in the PRB was also affected by flow rate. SO4 entered the PRB at 60 to 71 mg/L during the first trial. Under a HRT of 10 days it was depleted to detection limit after traveling through only 13% of the barrier. When HRT was decreased to 4.5 days, SO4 was able to penetrate the downgradient edge of the PRB at concentrations from 4 to 6 mg/L. With a 0.8 day HRT SO4 reduction was highly restricted as calculations showed 90% of available carbon in the PRB was being used to reduce NO3-N, compared to 7.5% being used for SO4 reduction at that time. In comparison, at the 10 day HRT, 61% of carbon being used for NO3-N reduction, 8.7% for SO4 reduction, 0.7 for dissolved oxygen and 29% was lost through DOC leaching. These calculations suggest that barrier efficiency can be greatly enhanced by manipulation of HRT through use of tile drains.

Enligt Svenskt Vatten ska dagvattensystem vara dimensionerade för att klara ett regnmed en återkomsttid på 10 år. För att utvärdera om ett system är rätt dimensionerat kanen dagvattenmodell upprättas. Det är då viktigt att veta vilka nivåer ledningarna har mendenna information är bristfällig hos många kommuner. Ledningarna borde dock följatopografin i generella drag och borde därför kunna uppskattas därifrån.Syftet med denna studie var därför att utveckla en metod för hur vattenledningarnasnivåer kunde ansättas på ett enkelt sätt utifrån marknivån och hur stor betydelse detskulle ha vid dagvattenmodellering. Ett ytterligare syfte var att även bedöma Lidingöstads dagvattensystem, där information om ledningarnas nivåer saknades, utifrån dennametod. För att metoden skulle vara användbar var det också viktigt att den var enkel attapplicera även för stora dagvattensystem.Delar av Sundbybergs dagvattennät i Stockholms län användes för att utvecklametoden. Där var ledningarnas nivåer kända och en analys av detta resulterade i enmetod där brunnarnas djup, som styr ledningarnas nivåer, ansattes på 2 m djup. Ettundantag var tvunget att göras vid de fall då ledningarna fick bakfall. Där ansattes ettdjup så att ledningen låg horisontellt.Vid utvärdering av hur stor påverkan ansättningen av djupet hade togs hänsyn tillosäkerheten av avrinningskoefficienten genom att använda tre olika scenarier;oförändrad, 30 % lägre samt 30 % högre avrinningskoefficient. För varje brunn vägdesrisken för översvämning ihop från resultatet av dessa tre scenarier och sammanställdesmed att varje brunns trycknivå fick status över mark, under mark eller osäker. Dettagjordes för både modell med kända och med ansatta nivåer. Statusen för varje brunnjämfördes sedan dem emellan för att utvärdera hur bra metoden för att ansättabrunnarnas djup var.Resultatet av studien visar att metoden i stora drag gav samma resultat vad gäller riskenför översvämning jämfört med om nivåerna hade varit kända. Avvikelser uppstodfrämst vid diken men även för enstaka instängda områden och utlopp. För Lidingösdagvattennät hamnade trycknivån för 18 % av brunnarna över marknivån vid ett 10-årsregn och ytterligare 16 % var osäkra. / According to The Swedish Water and Wastewater Association (SWWA), a storm waternetwork must be able to handle a rainfall with a return period of 10 years. In order toevaluate whether a drain system is adequately dimensioned, a storm water model can beestablished. This requires knowledge about the levels at which the conduits are situated,and this information is insufficient in many areas. However, the pipes could largely beassumed to follow the topography and the pipes levels can be estimated from it.Therefore, the aim of this study was to develop a method for how the level of stormwater conduits could be assessed from the ground level, and the significance thismethod had for storm water modeling. A further aim was also to, according to thismethod; assess the storm water systems of the Lidingö community, which lackedinformation on the pipe levels. Furthermore, for the method to be useful it wasimportant to make it easily applicable even to large storm water networks.The method was developed using parts of the storm water network in Sundbyberg,Stockholm. The levels of the conduits were known beforehand, and an analysis of themresulted in a method where the depth of the manhole, which controls the levels of theconduits, was estimated to 2 m. An exception had to be made when the conduits were inreverse slope, in which cases horizontal slope was assumed.When evaluating the impact from the depth assessment on the runoff, the uncertaintyfrom the imperviousness was taken into account by using three different scenarios;unchanged, 30% lower and 30% higher imperviousness. The risk of flooding for eachone of the manholes was weighted from the results of these three scenarios. Thisresulted in a pressure level for each manhole, either above ground, below ground orinconclusive. This was done for the model with both known levels for the conduits, andwith the assessed levels. In order to evaluate how well the method for applying thedepth worked, the status of each manhole was compared between the two models.The conclusion from this study was that the method developed here, more or less gavethe same results as when the levels of the conduits were previously known.Discrepancies arose mainly in ditches, but also for a few landlocked areas and outlets.For the Lidingö storm water network, 18 % of the wells ended up with a pressure levelabove ground when applied to a rain with a 10 year return period. Another 16 % of thewells were inconclusive.

The purpose of this report is to investigate the possibilities with drain water heat recovery (DWHR) in residential buildings. Information and relevant theory has been collected and summarized in this report. Calculations have been done for given scenarios to evaluate profits. DWHR heat exchangers use simple technology and have long life-time. The heat exchanger is connected to outgoing drainage pipe and incoming cold-water supply so countercurrent flow is accomplished. This makes it possible to increase the temperature of the incoming cold-water and thereby decrease the amount of energy used to heat water. There are mainly two types of models on the markets, vertically and horizontally heat exchangers. DWHR can be cost-effective if installed during new constructions or renovation, otherwise installation costs can be quite expensive. An installation of a DWHR-unit means no increasing risks of bacteria growth (legionella). Approximately 20 % of the energy used to heat hot-water can be counted as internal heat gain, with a DWHR heat exchanger the amount increases which will result in less energy consumed in the room heating system. More development of existing models is required to reduce the prices and spread information. A big advantage with DWHR is that the energy need for heating water is quite constant during the whole year compared to other demands, for example room-heating. Results from calculations in this report show that a reduction of 43 % of the heating demand for hot-water could be made in a normal family house and 17 % reduction could be made in a residential building with fifty apartments. / Syftet med arbetet är att undersöka möjligheterna med att återvinna värme från spillvatten i bostäder. Fakta och relevant teori inom området har samlats ihop och sammanfattats i denna rapport. Egna beräkningar har gjorts för att utvärdera hur mycket det är möjligt att återvinna. Tekniken för spillvattenvärmeväxling är enkel och växlarna håller i regel länge och kräver inget underhåll. En spillvattenvärmeväxlare kopplas in så att motströmsvärmeväxling uppnås. En växlare ansluts till utgående spillvattenledning och inkommande kallvattenledning. Ett problem är att de större växlarna för flerbostadshus kan vara platskrävanade och dyra. En installation av en växlare lämpar sig bäst vid nybyggnation för både småhus och flerbostadshus. Vid renoveringar av miljonprogrammen som uppfördes på 1960–70-tal finns det goda möjligheter att installera spillvattenvärmeväxlare då man genom exempelvis en stamrenovering gör ingrepp på befintliga ledningar, detta kan minska installationskostnaderna. Det finns inga tillkommande risker för legionellabakterier med spillvattenvärmeväxlare. Mer utveckling borde ske inom området så att nya modeller tillkommer. För nuvarande är den vertikala växlaren liten och passar bäst i småhus medan den horisontella växlaren passar bättre vid större anläggningar, med utveckling kan modellerna anpassas så de kan fungera oavsett användningsområde. I småhus bör man i första hand titta på andra åtgärder att för att minska energiförbrukningen, exempelvis driftoptimering, tätning av fönster, tilläggsisolering av vind m.m. En spillvattenvärmeväxlare kan istället vara ett alternativ för ett lågenergihus eller passivhus där vanliga åtgärder redan vidtagits. Ungefär 20 % av energiåtgången för tappvarmvatten kan tillgodoräknas som internvärme, med en installerad spillvattenvärmeväxlare ökar denna del vilket är bra då mindre effekt krävs till värmesystemet. En stor fördel som kan ses med spillvattenvärmeväxling är att tappvarmvattenförbrukningen är relativt konstant under året till skillnad från exempelvis värmebehovet. Utifrån givna scenarion visade beräkningarna i denna rapport att 43 % kunde besparas i småhus och 17 % i flerbostadshus.