<p>A lot of mine waste rock and tailings arise from all mining processes and have to be stored in an appropriate way. Tailings are deposited in impoundments retained by tailings dams. The objective of tailings dams is to retain the slurry from the mining process and in that way prevent spill into the surroundings that might be harmful for the environment. Tailings dams are often constructed as staged embankments so that construction costs and demand of materials are spread more evenly over the period of deposition.</p><p>The objective of this thesis has been to compile information about and evaluate events at Swedish tailings dams and also to develop a collective database for all Swedish mining companies for all tailings dams and all events that occur at tailings dams.</p><p>Information about 60 events at Swedish tailings dams has been gathered and evaluated. The evaluation has been performed by comparison between and analysis of individual parameters and also by use of a multivariate statistical method called PLS. The statistical analysis shows a decrease in the numbers of events during the last five years, which indicates improved dam safety within the mining industry. The analysis also shows that severe events and the human factor might be related when it comes to the initiating cause of the event. Further relations between the parameters and the severity of the events can be seen from the PLS-analysis, for example that low and short tailings dams to a greater extent are subjected to severe events. To be able to draw more reliable conclusions further studies with a more complete basic data are needed.</p><p>This work has shown a need of a collective database within the Swedish mining industry for tailings dams and occurring events at tailings dams so that more complete basic data could be obtained for future studies. A structure for such a database has been developed in Microsoft Access 2000. The aim of the database is to facilitate feedback within the mining industry and to gather comprehensive data for future statistical evaluations.</p> / <p>Vid alla gruvprocesser skapas stora mängder restprodukter i form av gråberg och anrikningssand som måste tas om hand på lämpligt sätt. Anrikningssanden deponeras tillsammans med vatten från gruvprocessen i magasin omgärdade av dammvallar, s.k. gruvdammar. Gruvdammar har som syfte att hålla kvar anrikningssand och vatten och måste vara stabila så att de skyddar omgivningen från utsläpp av anrikningssand som skulle kunna vara skadligt för miljön. En gruvdamm byggs ofta upp i etapper eftersom byggkostnaderna och behovet av dammfyllnadsmaterial då sprids över tiden.</p><p>Syftet med arbetet har varit att sammanställa och utvärdera händelser vid svenska gruvdammar samt att utforma ett för gruvindustrin gemensamt dammregister och felrapporteringssystem.</p><p>60 händelser vid svenska gruvdammar har sammanställts och utvärderats. Utvärderingen har genomförts dels genom att enskilda parametrar jämförts och analyserats och dels med hjälp av den multivariata analysmetoden PLS. Den statistiska analysen visar på en minskning i antal händelser under de senaste fem åren, vilket tyder på ett förbättrat dammsäkerhetsarbete inom gruvindustrin. Analysen har kunnat uppvisa ett samband mellan allvarliga händelser och den mänskliga faktorn när det gäller vad det är som initierat händelserna. Genom PLS-analysen har ytterligare samband mellan de undersökta parametrarna och allvarlighetsgraden av händelserna kunnat utläsas, bl.a. visar analysen att låga och korta dammar i större utsträckning drabbas av allvarliga händelser jämfört med höga och långa dammar. För att säkra slutsatser ska kunna dras krävs dock vidare studier med ett mer komplett statistiskt underlag.</p><p>Examensarbetet har påvisat ett behov av ett branchgemensamt damm- och felrapporteringsregister för att ett mer komplett underlag ska kunna erhållas i framtiden. En färdig databasstruktur för ett sådant dammregister och felrapporteringsregister för svenska gruvdammar har utformats. Databasen är uppbyggd i Microsoft Access 2000 och är tänkt att underlätta erfarenhetsåterföring inom branschen samt att ge ett underlag för framtida statistiska undersökningar.</p>

A lot of mine waste rock and tailings arise from all mining processes and have to be stored in an appropriate way. Tailings are deposited in impoundments retained by tailings dams. The objective of tailings dams is to retain the slurry from the mining process and in that way prevent spill into the surroundings that might be harmful for the environment. Tailings dams are often constructed as staged embankments so that construction costs and demand of materials are spread more evenly over the period of deposition. The objective of this thesis has been to compile information about and evaluate events at Swedish tailings dams and also to develop a collective database for all Swedish mining companies for all tailings dams and all events that occur at tailings dams. Information about 60 events at Swedish tailings dams has been gathered and evaluated. The evaluation has been performed by comparison between and analysis of individual parameters and also by use of a multivariate statistical method called PLS. The statistical analysis shows a decrease in the numbers of events during the last five years, which indicates improved dam safety within the mining industry. The analysis also shows that severe events and the human factor might be related when it comes to the initiating cause of the event. Further relations between the parameters and the severity of the events can be seen from the PLS-analysis, for example that low and short tailings dams to a greater extent are subjected to severe events. To be able to draw more reliable conclusions further studies with a more complete basic data are needed. This work has shown a need of a collective database within the Swedish mining industry for tailings dams and occurring events at tailings dams so that more complete basic data could be obtained for future studies. A structure for such a database has been developed in Microsoft Access 2000. The aim of the database is to facilitate feedback within the mining industry and to gather comprehensive data for future statistical evaluations. / Vid alla gruvprocesser skapas stora mängder restprodukter i form av gråberg och anrikningssand som måste tas om hand på lämpligt sätt. Anrikningssanden deponeras tillsammans med vatten från gruvprocessen i magasin omgärdade av dammvallar, s.k. gruvdammar. Gruvdammar har som syfte att hålla kvar anrikningssand och vatten och måste vara stabila så att de skyddar omgivningen från utsläpp av anrikningssand som skulle kunna vara skadligt för miljön. En gruvdamm byggs ofta upp i etapper eftersom byggkostnaderna och behovet av dammfyllnadsmaterial då sprids över tiden. Syftet med arbetet har varit att sammanställa och utvärdera händelser vid svenska gruvdammar samt att utforma ett för gruvindustrin gemensamt dammregister och felrapporteringssystem. 60 händelser vid svenska gruvdammar har sammanställts och utvärderats. Utvärderingen har genomförts dels genom att enskilda parametrar jämförts och analyserats och dels med hjälp av den multivariata analysmetoden PLS. Den statistiska analysen visar på en minskning i antal händelser under de senaste fem åren, vilket tyder på ett förbättrat dammsäkerhetsarbete inom gruvindustrin. Analysen har kunnat uppvisa ett samband mellan allvarliga händelser och den mänskliga faktorn när det gäller vad det är som initierat händelserna. Genom PLS-analysen har ytterligare samband mellan de undersökta parametrarna och allvarlighetsgraden av händelserna kunnat utläsas, bl.a. visar analysen att låga och korta dammar i större utsträckning drabbas av allvarliga händelser jämfört med höga och långa dammar. För att säkra slutsatser ska kunna dras krävs dock vidare studier med ett mer komplett statistiskt underlag. Examensarbetet har påvisat ett behov av ett branchgemensamt damm- och felrapporteringsregister för att ett mer komplett underlag ska kunna erhållas i framtiden. En färdig databasstruktur för ett sådant dammregister och felrapporteringsregister för svenska gruvdammar har utformats. Databasen är uppbyggd i Microsoft Access 2000 och är tänkt att underlätta erfarenhetsåterföring inom branschen samt att ge ett underlag för framtida statistiska undersökningar.

La complexification des intégrations sur les puces électroniques et la course à la miniaturisation sont les deux moteurs actuels de la microélectronique. Les limites optiques de la lithographie sont déjà atteintes depuis longtemps. Ainsi, la fabrication doit aussi être contrôlée de plus en plus étroitement afin d’éviter des variabilités qui nuiraient au bon fonctionnement du produit. Cette thèse présente une approche holistique du contrôle d’un des paramètres les plus importants de la photolithographie : le focus. Celui-ci est directement lié à la qualité de l’image transférée dans la résine photosensible pendant l’exposition. Son contrôle est donc primordial. Les sources de variabilités du focus sur le wafer sont multiples et diverses mais le cas particulier de la topographie du substrat a été privilégié dans cette étude. L’approche holistique de cet effet en particulier a conduit à l’utilisation d’outils de « data mining » telle la régression par la méthode des moindres carrés partiels qui a permis de pointer les principales causes de cette topographie, de créer un modèle prédictif de la topologie mais aussi d’évaluer des solutions d’améliorations comme l’amélioration des corrections qu’effectue le scanner permettant un meilleur contrôle généralisé de toutes les technologies sans toutefois changer l’intégration et le design ou encore la mise en place d’une méthode qui permet d’évaluer les erreurs de focus sur le wafer sans pour autant avoir recours à des mesures intensives sur silicium. D’autres solutions permettent de corriger les facteurs de risques à la source en modifiant le design afin de limiter la formation de la topologie de surface / The increasing complexity in chip integration (co-integration, increasing diversity of matérials…) and the race to dimension shrinkage are the two main drivers of research in microelectronics today. The optical limitations of lithography have been reached some years ago so that double patterning is now a typical process flow in production and helps reducing pattern size and increasing design density. Because of these, the manufacturing itself needs to be more tightly controlled in order to avoid marginalities. Which will affect the chip operation. The cross-effects between these elements are more numerous and their ratio in the total budget is larger whereas the needs for tighter process control are rising. This thesis presents a holistic approach of the control of one of the main parameters for photolithography: focus. It is directly linked to the quality of the image transferred into the photoresist during exposure. Its control is then essential. Variability sources for focus are manifold and diverse: laser, mask, optical column, servo-controllers, wafer flatness, integration, design, substrate reflectivity, material quality etc. All these are added to each other, leading to the creation of defects which can be catastrophic such as shorts. The first objective of this work was to show current challenges raised by STMicroelectronics new technologies, specifically photolithography-wise and focus-wise. A budget breakdown of two critical processes (Metal line patterning in 28nm FD-SOI and Contact patterning for 14nm FD-SOI) has been established which gives the impact of every effect. The product layout effects were evaluated to represent up to 20% of the complete budget and 50% of its intra-chip component. Topography contributes to a large part of these effects and offline measurements showed up to 32nm 3s of height variation in a single field. This may lead to local defocuses of the same order of magnitude. The usable depth of field being about 60 to 70nm for the studied layers, it is clear that focus control is really tight here. The holistic approach of topology leaded to the use of data mining tooling as PLS regression (Partial least Square). It allowed the highlighting of main causes of topography, the creation of a predictive model of topology and the evaluation of several improvement solutions. One may distinguish “palliative” and “curative” solutions. In the first category, on may put scanner levelling improvements which might be effective for every technology without any modification to make on integration and design. The emulated wafer map methodology providing on-product focus non-uniformities without any measurements is also a solution for investigation. “Curative” solutions may concern the mitigation of risk factors by modifying the design topography built-up main factors

90年代的後期，敏捷式系統發展方法開始被倡導。相對於傳統的系統發展方法，敏捷式系統發展方法著重於回饋機制而非事前的計畫、以人為中心而非以流程為中心。這樣的方法希望能助於提高組織對回應市場、客戶的效率，進而提高效益。目前在商場中使用此方法做為開發工具的企業仍是少數，本研究希望透過探討敏捷式系統發展方法論的使用時機來進行教學，進而得知系統開發人員對於接受敏捷式系統發展方法的關鍵因素，並藉此了解該如何在企業中導入此方法。本研究發現除了使用此方法的能力會影響影響使用意圖之外，在內在因素方面也包含了公司結構與團隊因素，外部因素則包含了顧客與成功案例因素，這些都是接受敏捷式系統發展方法的關鍵因素。本研究希望根據以上的分析結果，提出敏捷式系統發展方法導入之建議，提供組織做為參考用。 / Awareness of agile system development methodologies (SDM) has grown among information systems development community in recent years. Many of their advocates consider the agile and the plan-driven SDMs polar opposites. Indeed there are circumstances where agile SDMs are more suitable than plan-driven SDMs. Yet, there have been few studies on understanding developers’ adoption intention. This paper takes an initial attempt to gauge new generation of software developers’ intention to select agile SDMs. To many of these developers, agile SDMs are relatively new if not unheard of, in order to assess their intention to choose such category of methodologies, this research first introduced the methodologies to a group of 21 IS-major graduate students and discussed how and when to use agile SDMs. Then a survey was conducted, which was comprised of two parts of questions: agile SDM self-efficacy and intention to use. PLS analysis results showed that agile SDM self-efficacy influence the intention to use through performance outcome expectation, personal outcome expectation, and affect. Although the relationship between self-efficacy and anxiety was not confirmed, anxiety does affect intention to use. The fact that direct relationships between all four emotive variables and the intention to use are established implies that in order to encourage the use of agile SDMs, the focus should be emotive variables, and that self efficacy may be just one of various ways to promote the favorable emotional states. In addition, these participates were invited to a three-round Delphi test and analytic hierarchy process to retrieved their concerns about accepting or rejecting agile SDMs. Ten key factors were extracted and categorized. Adding up the pros and cons, team dimension is the most important dimension, which explains individual first concerns about how the collaboration when using agile SDMs. Other than team dimension, customer, corporate structure, project, success cases and methodology dimensions were consistent with the literatures. Thus our study provides a critical understanding of the factors that affect new generation of software developers’ intention to select agile SDM.