我國高速公路自通車以來，即有最高速限度９０公里，最低６０公里之限制，雖迭有 駕駛人反應希望放寬速限，卻因缺乏具體數據支持，遂無疾而疾。究竟速限帶給社會 的經濟效益如何？現行規定是否合理？若不合理，應如何訂定最適之速限？茲此第二 高速公路開工在即，實有必要深入探討，衡量速限對社會造成的利益與成本，據此客 觀地對速度規定上下限，以增進社會總體之福利。 本文擬就速限的成本面及效益面加以分析，成本面主要是速限造成的時間損失，效益 面則包括汽油的節省、意外事件減少所節約的人命、傷害損失，由於主要變數乃缺乏 具體市場價值的時間價值、生命價值，所以本文要旨即在於尋找較答觀的衡量標準， 再用成本效益分析評估速限政策的必要性。所採取資料係美國國家公路安全局的報告 ，以及各國學者對於時間、生命價值研究的實證，並由國內高速公路局的統計資料加 以分析，擬提出若干建議以供決策之參考。

The first chapter begins with the observations of 1,882 sources from the Bolocam Galactic Plane Survey (BGPS) at 1.1 mm in HCO⁺ J = 3 − 2 and N₂H⁺ J = 3 − 2. We determine kinematic distances for 529 sources and derive the size, mass, and average density for this subset of clumps. The median size of BGPS clumps is 0.75 pc with a median mass of 330 M⊙ (assuming T(Dust) = 20 K). The median HCO⁺ linewidth is 2.9 km s⁻¹ indicating the clumps are not thermally supported and provide no evidence for a size-linewidth relationship. This collection of objects is a less-biased sample of star-forming regions in the Milky Way that likely span a wide range of evolutionary states. We study in detail the G111 Infrared Dark Cloud northwest of NGC 7538 with the K-band Focal Plane Array. We map NH₃ (1,1) and (2,2), H₂O maser, and CCS emission simultaneously with the GBT. We find the NH₃ gas traces the 1.1 mm BGPS structure very well with gas kinetic temperatures consistently close to 15 K. Typical column densities are 2.5 × 10¹⁴ cm⁻² with a median abundance of NH₃ to H₂ of 5.94 × 10⁻⁸. The median linewidth of the NH₃ emission is 0.64 km s⁻¹ indicating the filament is not thermally supported. The NH₃ is subthermally populated along the entire filament. Individual NH3 peaks have a median size of 0.61 pc, mass of 188M⊙, and density of 3.4×10³ cm⁻³. An activity analysis shows the most active star forming regions are found at the junctions of the subfilaments that make up the larger G111 IRDC. The last chapter describes our systematic examination of individual student responses to the Light and Spectroscopy Concept Inventory national dataset. We use classical test theory to form a framework of results that is used to evaluate item difficulties, item discriminations, and the overall reliability of the LSCI. We perform an analysis of individual student’s normalized gains, providing further insight into the prior results from this data set. This investigation allows us to better understand the efficacy of using the LSCI to measure student achievement.

This study assesses the concerns of Jewish youth in Tucson, Arizona and reports their demographic characteristics and those of their families. Other issues explored are Jewish identity, family and peer relations, use of community resources, and program interests. The 382 Jewish youth surveyed in grades 4-12 were essentially an affiliated population with over 96% belonging to a Jewish religious institution, education program, or youth organization. The relationship was examined between Jewish youth concerns and family changes of single-parent and stepfamily living, dual careers, and interfaith marriage. Differences in concerns were also identified by gender, educational level, and affiliation. Results are also presented of a survey of 59 Jewish community resources concerning their utilization by parents and youth and their perception of youth concerns. Based on findings, recommendations are made to encourage Jewish community awareness and responsiveness to concerns and needs of Jewish youth and their families.

本篇論文主要在討論兩個人參選時的開票情況，研究「n+m人投票且無人投廢票的情況下，其中一人至少得n票且一路領先的開票方法數等於此人得n票的所有開票方法數」 ，第一章介紹研究動機及他人所使用的方式，使用路徑的方法證明一人得n票，另一人得m票，n≥m，得n票的人一路領先且勝出的方法數等於 C_n^(m+n)-C_(n+1)^(m+n)=C_m^(m+n)-C_(m-1)^(m+n)，再用計算相消的方式算出，此人至少得n票且一路領先的開票方法數等於此人得n票的所有開票方法數。 第二章介紹用一個折路徑的方法，將所有「一人得n票開票方法數」中非一路領先的路徑圖，經由一個壓扁、翻轉的摺紙方式，對應到「此人至少得n票且一路領先」的開票情況路徑圖，經由數學論證，這樣的路徑，是一對一且映成，並舉出兩個例子驗證其結果。 論文最後，提出一個猜想：若參選人數為三人時，其中一位參選人一路領先且勝出的開票方法數，應該可以用立體空間的方塊圖之路徑來證明。本篇論文，雖然沒有繼續討論這個有趣的問題，但也留下一個新的研究方向。 / The theme of this thesis is mainly to discuss of situation of counting and announcing the ballots in an election with two candidates. In explaining the contents of the "Total n+m votes, there’s no invalid vote. One candidate wins at least n votes and lead all the way. Under this circumstance this number of the way will be equal to all numbers of the way for these n votes of this candidate.” At first, we will introduce the methodology of the other adopt, the methodology of previous path of way proves one candidate known to have n votes, another candidate has m votes, the method of candidate with n votes who leads all the way and won will be equal to C_n^(m+n)-C_(n+1)^(m+n)=C_m^(m+n)-C_(m-1)^(m+n), and then result of calculating cancellation will prove this candidate will have at last n votes and leads the way to victory will be equal to all the methodologies of counting and announcing the ballots in this election. A method of flip the path will be introduced in the second chapter. Corresponding to the road map of ballot counting for the candidate who has n votes and lead the way to victory, the road map of same one with n votes without leading the way through a step-ping, flip the way of origami will be mathematically proves such reflect of the way will be reflect one to one and onto. By means of the discrete method is able to prove this result and the method to verify availability Finally, I would like to propose a surmise: If the number of candidates increased to 3, the methodology of the one who leads all the way should be able to use three-dimensional space of a block diagram of the path to prove. Although this thesis does not to continue pondering the interesting question, but also left a new research direction.

A spark ignition engine was retrofitted to operate on biogas fuel. Biogas was synthetically generated through the mixing of various pure gases. The air-fuel ratio was accurately controlled using a closed feedback system consisting of flow controllers and a wide range oxygen sensor. A natural gas catalytic converter was implemented with the use of biogas fuel. To achieve full NOx and CO reduction the engine was required to run at a slightly rich equivalence ratio. Methane emissions posed to be the hardest to reduce across the catalyst. The biogas fuel composition had no effect on the catalyst performance. The catalyst performance was only affected by exhaust temperature and equivalence ratio. The catalyst requires tight A/F ratio control for optimal performance. A Catalytic converter can be used to reach low emissions but requires the knowledge of the biogas fuel composition.

A spark ignition engine was retrofitted to operate on biogas fuel. Biogas was synthetically generated through the mixing of various pure gases. The air-fuel ratio was accurately controlled using a closed feedback system consisting of flow controllers and a wide range oxygen sensor. A natural gas catalytic converter was implemented with the use of biogas fuel. To achieve full NOx and CO reduction the engine was required to run at a slightly rich equivalence ratio. Methane emissions posed to be the hardest to reduce across the catalyst. The biogas fuel composition had no effect on the catalyst performance. The catalyst performance was only affected by exhaust temperature and equivalence ratio. The catalyst requires tight A/F ratio control for optimal performance. A Catalytic converter can be used to reach low emissions but requires the knowledge of the biogas fuel composition.

Star formation in the Milky Way is confined to star-forming regions (OB association, HII regions, and open clusters) in the Galactic plane. It is usually assumed that these regions are found preferably along spiral arms, as is observed in other spiral galaxies. However, young early-type stars are often found at high Galactic latitudes, far away from their birthplaces in the Galactic disc. These stars are called runaway stars, and it is believed that they were ejected from their birth- places early in their lifetimes by one of two mechanisms: ejection from a binary system following the destruction of the massive companion in a supernova type II event (the binary ejection mechanism), or ejection from a dense cluster following a close gravitational encounter between two close binaries (the dynamical ejection mechanism). The aims of our study were: to improve the current understanding of the nature of high Galactic latitude runaway stars, in particular by investigating whether the theoretical ejection mechanisms could explain the more extreme cases; to show the feasibility of using high Galactic latitude stars as tracers of the spiral arms. The main technique used in this investigation was the tracing of stellar orbits back in time, given their present positions and velocities in 3D space. This technique allowed the determination of the ejection velocities, flight times and birthplaces of a sample of runaway stars. In order to obtain reasonable velocity estimates several recent catalogues of proper motion data were used. We found that the evolutionary ages of the vast majority of runaway stars is consistent with the disc ejection scenario. However, we identified three outliers which would need flight times much larger then their estimated ages in order to reach their present positions in the sky. Moreover, the ejection velocity distribution appears to be bimodal, showing evidence for two populations of runaway stars: a “low” velocity population (89 per cent of the sample), with a maximum ejection velocity of about 300 kms−1, and a “high” velocity population, with ejection velo- cities of 400 – 500 kms−1. We argue that the observed bimodality and maximum ejection velocity of 500 kms−1 can be interpreted as a natural consequence of a variation of the binary ejection mechanism. A possible connection between the “high” velocity population and the so-called hypervelocity stars is also explored, resulting in the conclusion that some stars previously identified as hypervelocity may be in fact runaway stars. The feasibility of using stars as tracers of the spiral arms was tested on a local sample, in order to obtain better quality data and larger numbers. We found that the spiral arms pattern speeds estimated from this sample (24.9±5.2 kms−1 kpc−1) and from a selected sample of runaways (22.8 ± 7.8 kms−1 kpc−1) are consistent within the errors and also consistent with other published estimates. We concluded that our estimates combined with the ones obtained in other studies suggest a value in the range 20 − 25 kms−1 kpc−1 for the pattern speed. Moreover, we concluded that an adequate representation of the spiral arms is obtained given the former pattern speed estimate, even when applied to the sample of runaway stars.

We present a brief history of Galactic astrophysics, and explain the origin of halo substructure in the Milky Way Galaxy. We motivate our study of the dynamics of tidal streams in our Galaxy by highlighting the tight constraints that analysis of the trajectories of tidal streams can place on the form of the Galactic potential. We address the reconstruction of orbits from observations of tidal streams. We upgrade the geometrodynamical scheme reported by Binney (2008) and Jin & Lynden-Bell (2007), which reconstructs orbits from streams using radial-velocity measurements, to allow it to work with erroneous input data. The upgraded algorithm can correct for both statistical error on observations, and systematic error due to streams not delineating individual orbits, and given high-quality but realistic input data, it can diagnose the potential with considerable accuracy. We complement the work of Binney (2008) by deriving a new algorithm, which reconstructs orbits from streams using proper-motion data rather than radial-velocity data. We demonstrate that the new algorithm has a similar potency for diagnosing the Galactic potential. We explore the concept of Galactic parallax, which arises in connection with our proper-motion study. Galactic parallax allows trigonometric distance calculation to stars at 40 times the range of conventional parallax, although its applicability is limited to only those stars in tidal streams. We examine from first principles the mechanics of tidal stream formation and propagation. We find that the mechanics of tidal streams has a natural expression in terms of action-angle variables. We find that tidal streams in realistic galaxy potentials will generally not delineate orbits precisely, and that attempting to constrain the Galactic potential by assuming that they do can lead to large systematic error. We show that we can accurately predict the real-space trajectories of streams, even when they differ significantly from orbits.

This thesis is situated in the field of applied linguistics, education and European Studies. The empirical part examines outcomes in a two-way immersion (TWI) education model in Berlin (SESB) that go beyond linguistic or academic achievements. Based on a peace-linguistic framework established for the purpose of this study, this thesis assesses to what extent SESB programmes are associated with dimensions related to peace education, social capital and critical applied linguistics. Additionally, a teacher survey looks at attitudes towards bilingual and monolingual education and social integration. The findings are discussed in the framework of previous studies, chiefly from the USA, and in terms of language policy development in Germany and in Europe. This leads to a number of recommendations for stakeholders and policymakers. Employing a quasi-experimental design, involving a TWI and a control group, data were collected through a questionnaire survey of 14-18 year-old students (N=603) and teachers (N=32) in Berlin, which were analysed using primarily quantitative methods (including multiple regression) but with some qualitative elements. Based on statistically significant effects with at least small effect sizes, it was established that students in SESB had a greater sense of inclusion among classmates and greater conflict resolution skills than the control group. When looking at effects in subgroups (students with German, bilingual or non-German language backgrounds) there were also positive effects, however, the groups were affected in different ways, as is set out in this thesis. Furthermore, SESB also had a positive effect on relationships between parents and teachers, as well as on the students’ language attitudes and use patterns. In conclusion, it is argued that, besides personal and societal multilingualism, TWI programmes in Berlin are associated with greater potential for cohesion in the school class, and may benefit wider social integration of different language communities. Additionally, this thesis introduces German TWI programmes to an English-language audience.

A preliminary investigation of the added properties called added mass, added damping and added stiffness have been performed for a Kaplan turbine. The magnitude of dimensionless numbers have been used in order to classify the interaction of the fluid and the solid. The classification is done to bring clarity in which of the added properties are of importance for the system. The diameter of the runner and the hub have been calculated using the power output and the head for a Kaplan turbine. These dimensions have been used to determine the magnitude of the dimensionless numbers along with the velocity of the fluid. It turned out that all added properties affect the turbine, however, the magnitude of them are quite different. The magnitude of the added mass and the added damping are greater than the added stiffness, which often is neglected. The added mass can be determined if the natural frequencies of the structure in air and in water are known. The difference in natural frequencies can be used to determine the added mass factor and thereby the added mass of the system. The added damping can be determined by the change in damping ratio for different surrounding fluids. This was done using the simulation software ANSYS Workbench v.17.1, where two different types of simulation were used, ”acoustic coupled simulation” and ”two way coupled simulation”. The complexity of the geometry of the Kaplan turbine was simplified to a disc and a shaft. The result for the added mass was validated using results from an experiment [1]. The added damping could be determined, but not validated. The different types of simulation have been compared and it turned out that the added mass could be determined using ”acoustic coupled simulation” and ”two way coupled simulation”, but the added damping could only be determined using the ”two way coupled simulation”. / En preliminär undersökning av de adderade egenskaperna kallade, adderad massa, adderad dämpning och adderad styvhet har utförts för en Kaplan turbin. Magnituden av dimensionslösa tal har använts för att klassificera interaktionen av fluiden och soliden. Klassificeringen görs för att bringa klarhet i vilka av de adderade egenskaperna är av betydelse för systemet. Diametrarna för löphjulet och navet har beräknats utifrån effekt och fallhöjd för en Kaplan turbin. Dessa längder har använts för att bestämma magnituden av de dimensionslösa talen tillsammans med fluidens hastighet. Det visade sig att alla adderade egenskaper påverkar turbinen, men omfattningen av dem är helt annorlunda. Magnituden av den adderade massan och den adderade dämpningen är större än den adderade styvheten, som ofta försummas. Den adderade massan kan bestämmas om de naturliga frekvenserna av strukturen i luft och vatten är kända. Skillnaden i egenfrekvenser kan användas för att bestämma faktorn av den adderade massan och därigenom den adderade massan. Den adderade dämpningen kan bestämmas genom ändringen i dämpningsförhållande för olika omgivande fluider. Detta gjordes med hjälp av simuleringsprogrammet ANSYS Workbench v.17.1, där två olika typer av simulering användes, ”acoustic coupled simulation” och ”two way coupled simulation”. Komplexiteten i geometrin för en Kaplan turbin förenklades till en skiva och en axel. Resultatet för den adderade massan validerades med resultat från ett experiment [1]. Den adderade dämpningen kunde bestämmas, men inte valideras. De olika typerna av simulering har jämförts och det visade sig att den adderade massan kan bestämmas med hjälp av både ”acoustic coupled simulation” och ”two way coupled simulation”, men den adderade dämpningen kunde endast bestämmas med hjälp av ”two way coupled simulation”.