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by Wong Chun Wing = 銀膠媒介內結晶紫的表面增強共振拉曼散射研究 / 黃振榮. / Thesis submitted in: December 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 74-79). / Text in English; abstracts in English and Chinese. / by Wong Chun Wing = Yin jiao mei jie nei jie jing zi de biao mian zeng qiang gong zhen la man san she yan jiu / Huang Zhenrong. / Abstract --- p.1 / Chapter Chapter 1 --- Introduction --- p.2 / Chapter Chapter 2 --- Experimental Setup --- p.7 / Chapter 2.1 --- Raman probe --- p.7 / Chapter 2.2 --- Spectrophotometer for absorption spectra --- p.7 / Chapter 2.3 --- TEM and AFM --- p.8 / Chapter Chapter 3 --- Sample Preparation --- p.9 / Chapter 3.1 --- Chemicals --- p.9 / Chapter 3.2 --- Silver Colloid --- p.9 / Chapter 3.3 --- Slide Coated with Silver Colloid --- p.10 / Chapter 3.4 --- Sampling Probe --- p.10 / Chapter Chapter 4 --- Results and Discussion --- p.12 / Chapter 4.1 --- Dependence of SERRS on CV Concentration --- p.12 / Chapter 4.1.1 --- Resonant Raman spectra of CV --- p.12 / Chapter 4.1.2 --- TEM Images of Ag Colloid --- p.17 / Chapter 4.1.3 --- SERRS at different CV Concentrations in Solution --- p.20 / Chapter 4.2 --- Dependence of CV SERRS on Ag Concentration --- p.36 / Chapter 4.3 --- Dependence of CV SERRS on NaCl Concentration --- p.42 / Chapter 4.3.1 --- UV-VIR Absorption Spectra of NaCl added Ag Colloid --- p.42 / Chapter 4.3.2 --- Dependence on NaCl Concentration --- p.49 / Chapter Chapter 5 --- Conclusions --- p.64 / Appendix A / Chapter A.1(part A) --- Estimation of the Number Density of Colloidal Ag Particles --- p.66 / Chapter A.1(part B) --- Estimation of CV Concentration needed for Monolayer Coverage on Ag colloids --- p.67 / Chapter A.2 --- Assignments of Crystal Violet (CV) Vibrational Modes --- p.69 / Appendix B Estimation of the Probed Volume of the Microscope Objective --- p.70 / Appendix C Estimation of the Effective Molar Absorption Coefficient (α) of CV --- p.71 / References --- p.74

No / We describe a study conducted during 2009-12 into innovative assessment practice, evaluating an assessed coursework task on a final year Medical Genetics module for Biomedical Science undergraduates. An authentic e-assessment coursework task was developed, integrating objectively marked online questions with an online DNA sequence analysis tool (BLAST), routinely used by NHS and research professionals. The aim was to combine the assessment of understanding of complex module learning outcomes with real-world authentic skills highly valued in the work place. This approach challenges the oft-heard accusation that online computer-marked tests can lack validity and authenticity in higher education. The study demonstrates the content and construct validity of this form of e-assessment, showing that careful question design, allied with integration with the real life BLAST tool, enables instructors to assess complex higher order understanding, and requires students to demonstrate skills relevant for the work place. A study of three years of test results and measures of internal consistency data also show the reliability of this assessment. In addition, the results of surveys of student opinion and positive feedback from student module feedback questionnaires suggest that it is effective in terms of face validity.

The purpose of this research is to provide information about the psychometric properties of technology-enhanced (TE) items and the effects these items have on the content validity of an assessment. Specifically, this research investigated the impact that the inclusion of TE items has on the construct of a mathematics test, the technical properties of these items, and the influence these item types have on test characteristics. An empirical dataset was used to investigate the impact of including TE items on a multiple-choice (MC) assessment. The test used was the Iowa End-of-Course Algebra I (IEOC-A) assessment. The sample included 3850 students from the state of Iowa who took the IEOC-A assessment in the spring of 2012. The base form of the Algebra EOC assessment consisted of 30 MC items. Sixty TE items were developed and aligned to the same blueprint as the MC items. These items were appended in sets of five to the base form, in effect resulting in 12 different test forms. The forms were randomly assigned to students during the spring administration window. Several methods were used in an attempt to form a more complete understanding of the content characteristics and technical properties of TE items. This research first examined whether adding TE items to an established MC exam had an effect on the construct of the test. The factor analysis confirmed a two-factor model comprising latent factors of MC and TE items, indicating that TE items may add a new dimension to the test. Subsequent to these findings, a more thorough analysis of the item pool was conducted and IRT analyses were done to investigate item information, test information, and relative efficiency. This analysis indicated that there may be a difference in the way students perform on MC and TE items. There is evidence in this particular pool of items that there is a difference in these two item types. This difference may manifest itself as an additional, perhaps unintended, construct on the exam. Additionally, TE items may perform differently depending on the ability level of the student. Specifically, TE items may provide more information, and measure the construct more efficiently than MC items at higher levels of ability. Finally, the quantity of TE items included on a test has the potential to affect the relative efficiency of the instrument, underscoring the importance of selecting items that reinforce the purpose and uses of the test.

Sustainable and renewable energy is an incredibly important area in today’s society and investigation into avenues to improve this wide ranging technology are underway in many different fields. Thermoelectric devices possess the ability for the direct solid-state interconversion of heat and electrical power, which not only allows for sustainable refrigeration but also waste heat recovery. One current restriction on the efficiency of thermoelectric devices is the disparity in thermoelectric performance of p-type and n-type materials. Furthermore, a key physical attribute shared by the majority of high performing thermoelectric materials is low thermal conductivity. Thus in this thesis three separate p-type material systems exhibiting low thermal conductivity will be discussed. The Cu-excessed quaternary chalcogenides, CuM2InTe4 (M = Zn, Cd), and ternary chalcogenide, CuSbS2, were investigated due to their intrinsically low thermal conductivity. Whereas, skutterudites typically have good electrical properties but do not exhibit an intrinsically low thermal conductivity. Nevertheless low thermal conductivity can be achieved by taking advantage of their unique crystal structure by filling large voids with loosely bound atoms that act as phonon scattering centers. Therefore double-filled Fe substituted skutterudites with nominal compositions Yb0.4In0.02Co3FeSb12 and Yb0.8In0.02Co2.5Fe1.5Sb12 were also investigated. The CuM2InTe4 (M = Zn, Cd) and skutterudite specimens were synthesized by direct reactions, whereas the CuSbS2 specimens were synthesized by mechanical alloying. Structural and stoichiometric compositions were analyzed by a combination of X-ray diffraction, Rietveld refinement and energy dispersive spectroscopy. High-temperature transport properties were measured for all specimens and will be discussed in detail. The Cu-excessed quaternary chalcogenides display intrinsically low thermal conductivity that appears to be unaffected by the change in electrical properties that is a result of differing stoichiometries. This may provide a possible route to furthering the enhancement of the thermoelectric properties of these materials. Similarly the CuSbS2 ternary chalcogenides display a very low thermal conductivity due to stereochemically active lone-pair electrons and would potentially allow an optimization of the power factor without a significant increase of the very low thermal conductivity, thus improving the figure of merit. For the case of p-type skutterudites, (Yb, In) double-filled skutterudites have a maximum ZT of 0.6, which is promising in the hunt for improved p-type materials. This fundamental investigation provides insight that can lead to a deeper understanding of all three material systems outlined in this thesis and provides a platform for new research in the quest for materials suitable for thermoelectric applications.

<p>The traditional voice service in mobile networks is an important service that mobile users expect high quality from. With the convergence of mobile networks towards an all-IP network, an IP-based speech service becomes important which is referred to as Voice-over-IP (VoIP). The traditional voice service is highly optimized and a VoIP service must therefore fulfil strict quality requirements to provide the same speech service quality. The air interface technology, WCDMA, which is used in third generation communication systems in Europe is constantly developed. An improved concept for the mobile-to-network transmission, called the Enhanced Uplink (EUL) provides for higher uplink capacity for packet data services. It also includes features that may provide a sufficient VoIP service quality in mobile networks, when considering the uplink transmission. </p><p>The purpose of this thesis is to evaluate the VoIP capacity over EUL and identify crucial aspects of radio resource management in order to increase the capacity. This is done through dynamic system simulations, using a realistic VoIP traffic model. The VoIP capacity is also estimated by a derived theoretical framework.\newline </p><p>It is shown by simulation results and theoretical estimations, that power control is a vital mechanism in order to increase the capacity. Simulation results indicate that a VoIP over EUL capacity of 65\% of the traditional voice service capacity may be reached. The results also indicate that to improve the capacity for larger cells, the allowed VoIP packet delay must be increased.</p>

What constitutes a quality solution to an authentic task from industry? This study seeks to address this question through the examination of two expert solutions to an authentic engineering task used in the Chemical, Biological and Environmental Engineering curriculum at Oregon State University. The two solutions were generated by two teams of expert engineers with varying backgrounds. The experts solved a process development problem situated in the semiconductor manufacturing industry. Transcripts of audio recordings, design notebooks, and other work products were analyzed to identify common features in the two expert solutions. The study found that both experts placed a large focus on information gathering, modeling before experimentation, and fine tuning of the process. These solution features define a core set of expert competencies and facilitate understanding of high quality solution traits. An additional goal of the study was to identify competencies unique to each expert solution. It was observed that the expert teams used different proportions of first principles modeling and statistical experimental design to solve the problem. This proportion was dependent on the problem solver’s background and therefore should be expected to vary among student solutions. Implications of the work regarding instruction and assessment in engineering education are discussed. / Graduation date: 2012

Vertically aligned carbon nanotubes have been grown using Ni as catalyst by plasma enhanced chemical vapor deposition system (PECVD) in various pre-patterned substrates. Ni was thermally evaporated on silicon substrates with anodized alumina mask prepared in different methods including 2 step anodization of porous alumina template and interference lithography assisted array of pores. The templates helped to define Ni nanodots inside the pores which in turn catalyzed the growth of carbon nanotubes inside the PECVD system at temperature of 700-750C using mixture of ammonia and acetylene gases. The resulting well-aligned multi-walled carbon nanotubes were further investigated using SEM, TEM and Raman spectroscopy. The size, shape and structure of the grown carbon nanotubes were also discussed. / Singapore-MIT Alliance (SMA)

The importance of human resource development as a means of ensuring that the organisation and institution maintain their competitiveness cannot be over-emphasised. Training and development of employees are critical to organisations, because it ensures the acquisition of required skills, which is paramount for the provision of effective service delivery, in particular local sphere of government. The Workplace Skills training that refers to the strategic human resource training and development, aims at developing the workforce, labour skills capacity, thereby achieving the institutional goals, policies and objectives of the institution. The Workplace Skills Plan is the key strategic planning document relating to workplace training, career pathing and employment equity for the Municipality. It details the training planned by a municipality in a given financial year as legislated by the Local Government Sector Education Training Authority (LGSETA). Workplace Skills Plan, through LGSETA, the Skills Development Legislative framework and the Employment Equity Act, makes provision, ensuring that employees in the public service should enhance their skills in order to deliver effective services to its customers, the public. For quality and effective service delivery at the Nigel Local Municipality to take place, the implementation of the Workplace Skills training is imperative for the enhancement of a skill workforce that will be able to ensure that the customer is satisfied with the product and service rendered by the employees. / Thesis (M. Development and Management)--North-West University, Vaal Triangle Campus, 2009.

This project was a part of a study to evaluate natural attenuation (NA) as a viable remedial option for petroleum hydrocarbon (PHC) contamination at upstream oil- and gas-contaminated sites in Alberta, Canada. Laboratory mesocosms were set up using groundwater and sediment materials collected from two PHC contaminated sites (Site 1 and Site 3) in Alberta to investigate the enhancement of anaerobic PHC biodegradation by amendment of terminal electraon acceptors (TEAs, nitrate or sulfate) and/or nutrients (ammonium and phosphate). Multiple lines of evidence, including the removal of benzene, toluene, ethylbenzene and xylenes (BTEX) and CCME F1 fraction hydrocarbons (C6 to C10), rapid depletion of TEAs, the production of biogenic gases, and detection of the metabolites verified that anaerobic PHC biodegradation was occurring in both laboratory mesocosm studies. Selective biodegradation of PHCs under different reducing conditions was observed. However, there was no conclusive evidence that one reducing condition will universally favor the biodegradation of specific PHCs. In both studies, nutrient amendment showed no enhancement effects. The calculated first-order biodegradation rates in Site 1 mesocosm study ranged from 0.0032 to 0.033 d-1 for benzene, 0 to 0.028 d-1 for ethylbenzene, 0.0021 to 0.036 d-1 for m-, p-xylenes, and 0.0006 to 0.0045 d-1 for F1-BEX (F1 hydrocarbons exclduding BEX) under the tested conditions. The laboratory first-order biodegradation rates of BEX were higher than the estimated field rates, indicating the potential of enhanced anaerobic biodegradation in situ. However, when comparing the TEA amended mesocosms with the unamended controls (in which iron reduction might be the predominant process), the enhancement effects were less apparent and inconsistent. The calculated first-order biodegradation rates in Site 3 mesocosm study ranged from 0 to 0.0009 d-1 for benzene, 0 to 0.011 d-1 for ethylbenzene, 0 to 0.0016 d-1 for m- and p-xylenes, and 0 to 0.15 d-1 for o-xylene. Sulfate amendment significantly stimulated biodegradation of all xylenes and CCME F1 hydrocarbons. However, there was no definitive evidence that nitrate or sulfate amendment could enhance benzene or ethylbenzene biodegradation. / Environmental Engineering