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One of the major issues in surface coal mine land reclamation is the impact of total dissolved solids (TDS) on water quality. To address this issue, this study assessed whether vegetation could reduce TDS nutrient ion movement from the rooting zone in early reclamation stages when TDS generation is often highest. Vegetated and un-vegetated paired plots were established across eight sites with gradients in age, spoil material, and vegetative productivity. Ion exchange resin lysimeters were used to compare nutrient ion fluxes in soil solution that contribute to TDS between paired plots. Soil and vegetation properties (used as proxies for evapotranspiration and plant uptake) were characterized at each site and correlated with log ratios of common TDS contributing ions [i.e., base cations Ca2+, Mg2+, Na+, K+ (RBC), sulfate (RSO42-), and total Ca2+, Mg2+, Na+, K+, SO42- (Rtotal)] between un-vegetated and vegetated plots. Strong Spearman correlations were found between RTotal, RBC, and RSO42- during the peak growing season, and were weakened overall during vegetative dormancy. Soil organic matter was shown to be a strong correlate through dormant periods. Correlations between TDS nutrient ions and vegetation suggest evapotranspiration in the growing season, and interception during dormant periods, exert an influence on nutrient ion fluxes. These findings indicate that aggrading forests may reduce TDS nutrient ion loading, through solute retention mechanisms driven by organic matter inputs and plant uptake. / Master of Science

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The electric properties of materials in the THz spectrum are of significant interest for scientific research in the past two decades thanks to the development of THz-TDS systems. However, the measurement capability of the system is still bound by the low efficiency and instability of the system. In this work, a thorough assessment of the THz-TDS system is carried out in order to enhance the measurement capability of the system and provide guidelines for accurate and repeatable measurements. In Chapter 2, the operation fundamentals of THz-TDS systems including the generation and detection are reviewed. The limitations of THz-TDS systems are evaluated in the aspects of dynamic range, signal-to-noise ratio, and spectral resolution. The influence of systematic parameters are addressed and examined. In Chapter 3, a systematic characterisation of the performance of PCAs is performed. The performance of THz PCA is evaluated with respect to the intrinsic and extrinsic excitation parameters, as well as the power collection efficiency within the THz-TDS system. Performance evaluation is carried out in combination of experimental measurements and numerical modellings. Chapter 4 extensively investigates the sensitivity of the THz-TDS system regarding on misalignment of the components. An EM simulation model is built for the evaluation. Point E-field respond in frequency domain and time-domain are examined corresponding directly to the detection signal, and compared with lab measurements. The model is then extended to study the field distribution inside the system. Mode analysis of the field is conducted to discover the pattern of energy coupling related to misalignment. Chapter 5 aims to further enhance the efficiency and radiation characteristics of THz PCAs by adapting the concept of antenna array. The influence of array configuration is assessed by array factor analysis. Coupling conditions of array parameters are established. Performance dependences of THz PCAs on the array geometrics are extensively studied in theory, and tested against experiment. Chapter 6 assess the implementation of plasmonoic structures for the improvement of efficiency and power at the THz generation process. Fundamentals are discussed and structures are designed accordingly. Optimisation principles in consideration of the carrier properties are proposed and practised. Photoconductive antennas with plasmonic structures are fabricated and tested in a THz-TDS system, and the results are compared with simulation.

The aim of the study was to look at the differences in groups in Karlskrona Kommun in comparison to a larger population of work-groups in Sweden. The instrument used was the Team Diagnostic Survey developed by Ruth Wageman, J. Richard Hackman and Erin Lehman (2005) in order to diagnose the strengths and weaknesses in work-groups, as well as explore the group’s behaviours and effectiveness. The results show that there was a significant difference between the Karlskrona Kommun groups and the larger population of Swedish groups in the following areas: stable, clarity, challenge, diversity, whole task, resources and availability.

The occurrence of potentially hazardous chemical constituents (PHCC) in subterranean water and the divergent potential for bioaccumulation in different production systems, made it necessary to investigate the effect of alleviator treatment on the accumulation of PHCC in broiler tissues. Local poultry producers are faced with the opportunities to expand their poultry products to overseas countries, therefore, the quality measures must be in place to comply with strict quality control systems like the European Union standards. The effect of water quality on the health and production parameters in broilers and layers has recently been questioned as to its compliance with both the export and local markets. The effects of water quality constituents (WQC) are a function of the type and character of the WQC, the intake rates and exposure to WQC, the type of animal and its physiology and the demands of the environment. Where the livestock and humans use the same water source, the livestock can be an effective indicator species of the risk posed to humans. The study evaluated the effectiveness of TOS and Br as possible alleviators of PHCC accumulation in broiler tissues grown under intensive production system. Broilers received four types of treatment: control (<500 mg/L IDS; < 0.005 mg/L Br + As + Pb), elevated elements (As=0.1 mg/L; Br=1 mg/L; Pb=0.1mg/L), elevated elements + 1500 mg/L TOS and control + 1500 mg/L TOS in drinking water from one day to 42 days old. The accumulation of PHCC in broiler tissue did not exceed maximum allowable concentrations (EU - MAC) during a short period of exposure. The groups that received TOS retained the lowest PHCC accumulation. These results suggest that TOS plus bromide in broilers' drinking water could alleviate arsenic and lead accumulation in broilers' tissues. However, the alleviation was not always significant in all the tissues. / Dissertation (MSc(Agric))--University of Pretoria, 2009. / Animal and Wildlife Sciences / unrestricted

我國PC(個人電腦，Personal Computer)產業產值佔全球的60%以上，但幾乎97%以上都是為人作嫁，替他廠牌代工，在辛苦、薄利的製造領域鑽營7%不到的毛利。反觀一些品牌大廠卻能在買賣之間，獲得近乎製造兩倍以上的毛利，並且將庫存風險、交運、售後服務等煩瑣的業務要求製造者承擔。尤其筆記型電腦因體積小，CTO (Configure To Order)與CDS (China Direct Shipment)能力成為國際品牌大廠評核製造者能力的必要條件。 更因為市場競價的關係，品牌廠商以比價、競價、公開成本資訊的手法，遊走於我製造廠之間，把代工利潤壓到微乎其微的地步。製造廠只好移廠大陸，尋求更低廉的製造成本，並且擴大產能、執行垂直整合，意圖以規模經濟和範疇經濟來彌補獲利的不足。 本研究以Dorothy的企業核心能力與知識創造活動理論為依據，探討我國筆記型電腦業者發展CTO/CDS的知識創造活動和技術跨國移轉問題，並以價值鏈分析，探討我國筆記型電腦業者在產業國際分工移轉過程中所扮演的角色。全文分四大部份： 1. 文獻探討：以專家的理論作為本研究的基礎，一方面使本研究有所依據，快速進行；另一方面可驗證理論的實用性。 2. CTO/CDS實務研究：CTO/CDS的實現必須仰賴強大的資訊系統支援，本研究一方面提供CTO/CDS的電腦化實務經驗供產業參考；另一方面以CTO/CDS系統為例，探討我國筆記型電腦的實體系統和技術能力。 3. 知識創造活動研究：以一家公司為個案深入探討，再輔以其他四家公司訪談資訊相比對印證，研究筆記型電腦產業知識創造的過程和應用，以期提升活用知識的能力。 4. 價值鏈與創新模型分析：研究產業價值鏈各階段的附加價值貢獻，我國業者的能力、秉賦和扮演的角色，以期往高附加價值領域開拓。 最後希望能藉由結論，串連「實體系統、技術能力」→「活用知識」→「高附加價值」而建議出「贏的策略」。 本文僅研究者個人的意見，在有限的研究領域裡提出心得與建議，若能為產業所認同，實感榮幸。但產業環境複雜，要考慮的因素相當多，諾大疏漏的領域，祈望產業先進及專家學者多加批評指教！ / Although the PC production value of Taiwan is beyond 60% to the world, most of them were made by term of OEM/ODM. Taiwan PC companies earned no more than 7% gross profit through their hard production routine. Not only the brand-named companies could earn double just by trade, but also they asked the makers to bear the risk of inventory, delivery and service jobs. Especially, because of the small size of notebook, CTO/CDS capability became the “must criteria” when the brand-named companies survey the producers for OEM/ODM. Due to the market price competition, brand-named companies strangulated the profit of makers by way of bidding and cost analysis. Taiwan makers had no choice but to move their works to Grand China for the purpose of lower cost. They enlarged the production capacity and diversified the PC production by vertical integration, in order to cover the shortage of profit by economic of scale and scope. This thesis was base on theory of Dorothy Leonard-Barton“ Wellsprings of Knowledge: Building and Sustaining the Sources of Innovation”, researched the issues of CTO/CDS knowledge development and cross-national shift of skill of Taiwan NB makers, and also studied the roles that Taiwan makers played at the value chain of NB industry. The article can be divided into the following four parts according to their different natures: 1. Review of academic papers: The basic theories that can make the study going smoothly and rapidly. 2. Study of CTO/CDS practice: To study the CTO/CDS information system and skill, and provide CTO/CDS practice for reference. 3. Study of knowledge creation activities: A deep case study plus the surveys of the other four companies describe the process of knowledge creation and skill innovation in order to enhance the application ability of knowledge. 4. Value chain and innovation model analysis: To study the added value of each segment in the NB value chain, and the industry innovation model to find out Taiwan NB makers’ ability and capability. Finally, I try to come out the “winner strategies” by integrating “ systems”, “abilities”, “capacities”, “knowledge” and “high value” in the ending. All deductive inferences of this limited research are my personal viewpoints only. I will be very proud if they can be recognized by others. Actually, the business environment is more complex than what we think. Any comments, views and opinions toward this paper are welcome and will be highly appreciated.

In the last two decades, advances in the dark field detectors and microscopes of scanning transmission electron microscopy (STEM) have inspired a resurgence of interest in quantitative STEM analysis. One promising avenue is the use of STEM as a nanothermometric probe. In this application, thermal diffuse scattering, captured by a CCD camera or an annular dark field detector, acts as an indirect measurement of the specimen temperature. One challenge with taking such a measurement is achieving adequate sensitivity to quantify a change in scattered electron signal on the order of 1% or less of the full electron beam. Another difficulty is decoupling the thermal effect on electron scattering from scattering changes due to differing specimen thicknesses and materials. To address these issues, we have developed a method using STEM, combined with electron energy loss spectroscopy (EELS), to produce a material-specific calibration curve. On silicon, across the range 89 K to 294 K, we measured a monotonically increasing HAADF signal ranging from 4.0% to 4.4% of the direct beam intensity at a thickness-to-mean-free-path ratio of 0.5. This yielded a calibration curve of temperature versus full-beam-normalized, thickness-normalized HAADF signal. The method enables thermal measurements on a specimen of varying local thickness at a spatial resolution of a few nanometers. We demonstrated the potential of the technique for testing electron scattering models by applying single-electron scattering theory to the data collected to extract a measurement of the mean atomic vibration amplitude in silicon at 294 K. The measured value, 0.00738 ± 0.00002 nm, agrees well with reported measurement using X-rays.

Le dioxyde d'uranium UO2 est le combustible nucléaire standard des réacteurs à eau pressurisée. Durant le fonctionnement du réacteur, la fission de l'uranium produit une grande variété de produits de fission, parmi lesquelles des gaz de fission, principalement le xénon et le krypton. En raison de leurs propriétés, ces gaz peuvent fortement impacter le comportement du combustible, et c’est pourquoi la maitrise de leur comportement est un enjeu industriel majeur et que de nombreux efforts de modélisation y sont consacrés depuis plusieurs dizaines d’années.Cette étude se base sur l’idée que la capacité prédictive des modèles de gaz est limitée par une description insuffisante des défauts ponctuels et de leurs interactions avec les atomes de gaz. Dans ce contexte, on applique à l’UO2 la Dynamique d’Amas, technique largement utilisée notamment pour décrire l’évolution de la concentration des défauts ponctuels et agrégés dans les métaux sous irradiation. Ce travail met plus particulièrement l’accent sur l’interprétation d’expériences de diffusion de gaz rares implantés dans l’UO2, en faisant appel au maximum à des résultats de modélisation atomistique pour évaluer les paramètres du modèle. / During in-pile irradiation of nuclear fuels a lot of rare gases are produced, mainly xenon and krypton. The behaviour of these highly insoluble fission gases may lead to an additional load of the cladding, which may have detrimental safety consequences. For these reasons, fission gas behaviour (diffusion and clustering) has been extensively studied for years.In this work, we present an application of Cluster Dynamics to address the behaviour of fission gases in UO2 which simultaneously describes changes in rare gas atom and point defect concentrations in addition to the bubble size distribution. This technique, applied to Kr implanted and annealed samples, yields a precise interpretation of the release curves and helps justifying the estimation of the Kr diffusion coefficient, which is a data very difficult to obtain due to the insolubility of the gas.