Students' perceptions of learning through assessment for learning and technology.

This study investigates the implementation of the concept of assessment for learning in the context of computer education courses in teacher education in Macau. It aims to promote reflection in students' learning with the use of technology. The concept of assessment for learning was infused into the courses taught by the researcher. Opportunities for self-assessment, peer-assessment and constructive feedback were set up for students to examine their own learning through the online technoiogy, of blogging and digital portfolios. One hundred and seventeen teachers and teacher candidates, taking Computer, Applications, Educational Technology and Information Technology in Education experienced a curriculum based on the concept of assessment for learning for a period of thirteen to fourteen weeks. Nineteen of them experienced a longer period of about twenty-seven weeks. Students were requested to reflect on the course content weekly using blogs and the journal content of the blogs serves as the main source for data analysis. In addition, a questionnaire was given to students to seek their v'iew on the use of blogs for reflection and communication purposes. Analysis of data from different sources such as questionnaire, students' journals and their digital learning portfolios show that students do engage in the reflective process. However, the quality of reflection for most students was not deep. Students did make use of the journal to communicate with. the tutor. The communication pattern of students using online environment shows that they support their peers by words of encouragement, affirmation and empathy. Students value the feedback provided by both the tutor and their classmates. Major problems encountered by students are: the requirement to write a weekly journal and knowledge of what constitutes reflective journal content. The study concludes that assessment for learning is a viable approach that can be supported through blog and digital portfolios. However, the successful implementation of the assessment for learning requires the active facilitation of the tutor to engage students in the process of reflection and communication.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

EClass: An execution classification approach to improving the energy-efficiency of software via machine learning

Energy efficiency at the software level has gained much attention in the past decade. This paper presents a performance-aware frequency assignment algorithm for reducing processor energy consumption using Dynamic Voltage and Frequency Scaling (DVFS). Existing energy-saving techniques often rely on simplified predictions or domain knowledge to extract energy savings for specialized software (such as multimedia or mobile applications) or hardware (such as NPU or sensor nodes). We present an innovative framework, known as EClass, for general-purpose DVFS processors by recognizing short and repetitive utilization patterns efficiently using machine learning. Our algorithm is lightweight and can save up to 52.9% of the energy consumption compared with the classical PAST algorithm. It achieves an average savings of 9.1% when compared with an existing online learning algorithm that also utilizes the statistics from the current execution only. We have simulated the algorithms on a cycle-accurate power simulator. Experimental results show that EClass can effectively save energy for real life applications that exhibit mixed CPU utilization patterns during executions. Our research challenges an assumption among previous work in the research community that a simple and efficient heuristic should be used to adjust the processor frequency online. Our empirical result shows that the use of an advanced algorithm such as machine learning can not only compensate for the energy needed to run such an algorithm, but also outperforms prior techniques based on the above assumption. © 2011 Elsevier Inc. All rights reserved.postprin

CrowdAdaptor: A Crowd Sourcing Approach toward Adaptive Energy-Efficient Configurations of Virtual Machines Hosting Mobile Applications

Applications written by end-user programmers are hardly energy-optimized by these programmers. The end users of such applications thus suffer significant energy issues. In this paper, we propose CrowdAdaptor, a novel approach toward locating energy-efficient configurations to execute the applications hosted in virtual machines on handheld devices. CrowdAdaptor innovatively makes use of the development artifacts (test cases) and the very large installation base of the same application to distribute the test executions and performance data collection of the whole test suites against many different virtual machine configurations among these installation bases. It synthesizes these data, continuously discovers better energy-efficient configurations, and makes them available to all the installations of the same applications. We report a multi-subject case study on the ability of the framework to discover energy-efficient configurations in three power models. The results show that Crowd Adaptor can achieve up to 50% of energy savings based on a conservative linear power model.published_or_final_versio

IVHS Education Program

https://deepblue.lib.umich.edu/bitstream/2027.42/154098/1/gillespie1990.pd

Periodic chiral magnetic domains in single-crystal nickel nanowires

We report on experimental and computational investigations of the domain structure of ~0.2 x 0.2 x 8 {\mu}m single-crystal Ni nanowires (NWs). The Ni NWs were grown by a thermal chemical vapor deposition technique that results in highly-oriented single-crystal structures on amorphous SiOx coated Si substrates. Magnetoresistance measurements of the Ni NWs suggest the average magnetization points largely off the NW long axis at zero field. X-ray photoemission electron microscopy images show a well-defined periodic magnetization pattern along the surface of the nanowires with a period of {\lambda} = 250 nm. Finite element micromagnetic simulations reveal that an oscillatory magnetization configuration with a period closely matching experimental observation ({\lambda} = 240 nm) is obtainable at remanence. This magnetization configuration involves a periodic array of alternating chirality vortex domains distributed along the length of the NW. Vortex formation is attributable to the cubic anisotropy of the single crystal Ni NW system and its reduced structural dimensions. The periodic alternating chirality vortex state is a topologically protected metastable state, analogous to an array of 360{\deg} domain walls in a thin strip. Simulations show that other remanent states are also possible, depending on the field history. Effects of material properties and strain on the vortex pattern are investigated. It is shown that at reduced cubic anisotropy vortices are no longer stable, while negative uniaxial anisotropy and magnetoelastic effects in the presence of compressive biaxial strain contribute to vortex formation.Comment: 15 pages, 11 figure

A highly sensitive mean-reverting process in finance and the Euler-Maruyama approximations

Empirical studies show that the most successful continuous-time models of the short term rate in capturing the dynamics are those that allow the volatility of interestchanges to be highly sensitive to the level of the rate. However, from the mathematics, the high sensitivity to the level implies that the coeffcients do not satisfy the lineargrowth condition, so we can not examine its properties by traditional techniques. This paper overcomes the mathematical difculties due to the nonlinear growth and examines its analytical properties and the convergence of numerical solutions in probability. The convergence result can be used to justify the method within Monte-Carlo simulations that compute the expected payoff of financial products. For illustration, we apply our results compute the value of a bond with interest rate given by the highly sensitive mean-reverting process as well as the value of a single barrier call option with the asset price governed by this process

從《論語》看孔子與《易傳》之關係

歷來言《易傳》作者，或以爲出孔子之手，或以爲非孔子所作，莫衷一是。本文在前賢研究基礎上，從《論語》入手，找出書中孔子言論與傳世《易傳》内容相似之處，共得１７ 條，所言道理，包括朋友講習、改過遷善、節用愛民、慎言節食、敬義立德、寡慾致剛、不貳己過、順言以悦、非禮勿履、尊卑有序、止息争訟、赦過宥罪、思不出位、君子固窮、裒多益寡、修美文德、不言而行。以上諸點，《論語》與《易傳》立論，互爲表裏。據此，知孔子之於《易傳》，雖無撰述之實，或有闡述之功。本文證明《論語》與《象傳》及《彖傳》具密切關係，此對孔子闡述《易傳》之説，或可提供足資參考之佐證

“孟子深於《易》”論

趙岐《孟子題辭》謂孟子“通‘五經’，尤長於《詩》、《書》”。今觀《孟子》徵引《詩》、《書》者甚衆，然未見引《易》之例，學者或置疑孟子未嘗論《易》。查《孟子》一書闡發《易》理之處甚多，特未明言之矣。本文梳理《孟子》學説合乎《易》義者共二十例，所涉内容，包括義利之辨、與民同樂、“時”之觀念、仁者樂天、大勇、勿正勿忘、善與人同、正位與大道、性善説等，涵蓋孟子主要學説。此二十條，直接闡發《周易》正文者，有《豫》卦、《復》卦、《恒》卦、《大過》卦、《小畜》卦、《大畜》卦及《无妄》卦，其餘皆與《易傳》（包括《彖》、《象》、《文言》、《説卦》及《序卦》）之義相通。至於孟子是否闡發《易傳》之義，此中牽涉《易傳》、《孟子》寫作年代孰先孰後問題。本文參考近人李零、金景芳、李學勤之説，認爲《易傳》之成書，當在《孟子》之前，而《孟子》一書闡發《易傳》之可能性爲大。退一步而言，《易傳》縱或有後人因《孟子》學説而補入之言論，然二者闡發《周易》之義，亦理無二致。故焦循“孟子深於《易》”論，其説當可確立也