A new starting profile, instead of ANSI C82.11, is defined to illustrate the starting transient of rapid-start fluorescent lamps driven by high-frequency electronic ballasts. By scrutinizing the lamp voltage and current waveforms, the starting transient can be classified into preheating, glow, and glow-to-arc stages. By the new definition, the starting characteristics of all ballast-lamp circuits can be well interpreted. To investigate the starting performance, a test system is set up. Experimental results show that the time required for glow and glow-to-arc stage is significantly affected by the starting voltage, the filament preheating and the environment temperature. On the basis of the in-depth analysis on the investigated results, the starting characteristics of rapid-start fluorescent lamps are well understood, providing useful information for designing the starting scenario for the ballast.

Owing to the booming development of the WWW, it creates many new challenges for information filtering. Information Filtering (IF) is an area of research that develops tools for discriminating between relevant and irrelevant information. IF can find good matches between the web pages and the users' information needs. Users first give descriptions about what they need, i.e., user profiles, to start the services. A profile index is built on these profiles. A series of incoming web pages will be put into the matching process. Each incoming web page is represented in the same form of the user profile. In this way, the users who are interested in an incoming web page can be identified by comparing the descriptions of the web page with each user profile. At last, the web page will be recommended to the users whose profiles belong to the filtered results. Therefore, a critical issue of the information filtering service is how to index the user profiles for an efficient matching process. When we index the user profile, we can reduce the costs of storage space and the processing time for modifying the user profiles. In this thesis, first, we propose a count-based tree method, which takes the count of each keyword into consideration, to reduce the large storage spaces as needed by the tree method. Next, three large-itemset-based methods are proposed to reduce the storage space, which are called the count-major large itemset method, the weighted large itemset method and the hybrid method. In these three large-itemset-based methods, we first cluster profiles with similar interests into the same group. Next, for each cluster, we apply the mining association rules techniques to help us to construct the index strategies. We design three methods by using the idea of the Apriori algorithm which is one of well-known approaches in mining association rules. But, we modify the minimum support and the goal in the Apriori algorithm. We may not always output the large itemset Lk. That is, we may only use Lw, where w < k. In summary, the cost of storage spaces of our four methods are less than that of the tree method proposed by Yan and Garcia-Molina. According to our simulation results, each of our four methods may provide the best result when different input data sets. Next, we propose a large-itemset-based approach to the incremental update of the index structure for storing keywords to reduce the update cost. When someone's interests are often changed, we must care about the way how to provide the low update cost of the index structure. We take the weight of each keyword into consideration. That is, each keyword can be distinguished the long-term interest which has weight above the threshold from the short-term interest which has weight below the threshold. Owing to that the probability of modifying the short-term interests is higher than that of modifying the long-term interests, we can update the short-term interests locally. According to our simulation results, our method really can reduce the update cost as needed by Wu and Chen' methods.

In this thesis, we propose a data mining approach to recommending library new books that have never been rated or borrowed by users. In our problem context, users are characterized by their demographic attributes, and concept hierarchies can be defined for some of these demographic attributes. Books are assigned to the base categories of taxonomy. The proposed approach starts with the identification of the type of users who are interested in some specific type of books. We call such knowledge generalized profile association rules. Less interesting or redundant generalized profile association rules are then pruned to form a concise rule set. The resultant rule set is then used for promotion of new books. We develop a new definition of rule interestingness with respect to book recommendation, propose an approximation scheme for estimating the interestingness of a rule, and construct a scheme to effectively conduct new book recommendation by using the interesting rules. We finally apply the book circulation data of a university library to the proposed approach for performance evaluation.

Semiparametric models play important roles in the &#64257;eld of biological statistics. In this dissertation, two types of semiparametic models are to be studied. One is the partially linear model, where the parametric part is a linear function. We are to investigate the two common estimation methods for the partially linear models when the data is correlated — longitudinal or clustered. The other is a semiparametric model where a latent covariate is incorporated in a mixed effects model. We will propose a semiparametric approach for estimation of this model and apply it to the study on colon carcinogenesis. First, we study the pro&#64257;lekernel and back&#64257;tting methods in partially linear models for clustered/longitudinal data. For independent data, despite the potential rootn inconsistency of the back&#64257;tting estimator noted by Rice (1986), the two estimators have the same asymptotic variance matrix as shown by Opsomer and Ruppert (1999). In this work, theoretical comparisons of the two estimators for multivariate responses are investigated. We show that, for correlated data, back&#64257;tting often produces a larger asymptotic variance than the pro&#64257;lekernel method; that is, in addition to its bias problem, the back&#64257;tting estimator does not have the same asymptotic ef&#64257;ciency as the pro&#64257;lekernel estimator when data is correlated. Consequently, the common practice of using the back&#64257;tting method to compute pro&#64257;lekernel estimates is no longer advised. We illustrate this in detail by following Zeger and Diggle (1994), Lin and Carroll (2001) with a working independence covariance structure for nonparametric estimation and a correlated covariance structure for parametric estimation. Numerical performance of the two estimators is investigated through a simulation study. Their application to an ophthalmology dataset is also described. Next, we study a mixed effects model where the main response and covariate variables are linked through the positions where they are measured. But for technical reasons, they are not measured at the same positions. We propose a semiparametric approach for this misaligned measurements problem and derive the asymptotic properties of the semiparametric estimators under reasonable conditions. An application of the semiparametric method to a colon carcinogenesis study is provided. We &#64257;nd that, as compared with the corn oil supplemented diet, &#64257;sh oil supplemented diet tends to inhibit the increment of bcl2 (oncogene) gene expression in rats when the amount of DNA damage increases, and thus promotes apoptosis.

Using the envelope theory, the mathematical model of the end face profile and the working tool path of a special optical fiber polishing machine is deve- loped in this study. During the polishing process, the polisher is controlled by three parameters including the fiber rotational angle, the height H and the angle between the fiber and polisher. The contact points between the optical fiber and the polishing plate will determine the profile of the fiber end face. The 3-D end face with double-variable curvatures can be fabricated by properly controlling these three parameters. Since the grinding (polishing) material removal rate is related to machining time and normal contact force, the grinding (polishing) tool path and parameters are needed some modification in order to get the precise end profiles. Example of fiber end faces of 2-D elliptical face and 3-D ellipsoid are given to check the developed mathematical model in this study by computer solid modeling.

With increasing demands on environmental protection in recent years, the Government agency concerned has recently proposed the strategies for shore protection and management, which aim for prevention and mitigation of coastal disaster and reduction in coastal erosion, as well as the creation of an environment with focus on landscape, ecology and community recreation. Soft and quasi-natural approach will be implemented to restore the glory of a stable coast. Based on the consideration of disaster prevention, this study investigates the beach profile changes, which include beach berm erosion and bar formation resulting from storm waves with different return periods. The SBEACH model is used to estimate the beach changes subject to variable conditions of beach berm width, medium sand grain diameter, beach slope and design water level etc. Regression analysis is then applied to establish a relationship between the storm beach buffer width and relevant physical parameters. Prior to this, the results of large wave tank tests on beach profile changes conducted by Coastal Engineering Research Center in the United States are used to calibrate the two main parameters K and £` used in SBEACH model. Beach profile changes can now be estimated systematically using a set of modified K and £` values. After having performed a series numerical studies, we may conclude that: (1) With storms of different return periods but identical non-dimensional fall velocity (H0/£sT), berm erosion increases and the location of the bar becomes further offshore as storm return period increases ; (2) With different sand grain sizes subject to identical storm wave conditions, beach berm erosion increases as grain size increased, but shoreline retreat decreases; and location of bar is further offshore for a beach consisting smaller sand grains; (3) Under the same storm return period and sand grain diameter (i.e., similar non-dimensional fall velocity), berm erosion increases as storm intensity and design water level increase, but shoreline retreat decreases and bar is located nearer; and vice versa; (4) from a series of calculations based on different sand grains and storm beach buffer width, it is found that larger buffer is required for beach with smaller grain size, in order to absorb the storm wave energy.

Thesis (M.S.)--Missouri State University, 2009. / "May 2009." Includes bibliographical references (leaves 21-24). Also available online.

Abstract Title: The picture of Studenthälsan – a focus group study of the image that students in Uppsala have of the organization and of how they look at the way the organization addresses them. Studenthälsans image - en fokusgruppundersökning omUppsalastudenternas bild av organisationen och dess sätt att tilltala dem Number of pages: 65 (73 including enclosures) Author: Sofie Backman Tutor: Göran Svensson Course: Media and Communication Studies C Period: Fall 2007 University: Division of Media and Communication, Department of Information Science, Uppsala University Aim: The aim of this essay is to study the image that students in Uppsala have of Studenthälsan and its excersice department. This includes how the students perceive the organization’s way of communicating with them, both in terms of the marketing and their reception at the facilities, and what they would like to be different regarding this in the future. Method/Material: Together with literature studies, a qualitive method has been used and three focus group interviews with a total of 15 informants have been conducted. One group contained students that are customers of Studenthälsan, one group contained only students that use anther training facility, and a third group was a mixed group which combined both students training at Studentälsan and elsewhere. Main Results: The main results from the focus group interviews show that theimage of Studenthälsan varies among the students. The studentsthat use or have used the facilities are generally slightly more positive about the organization. Generally, students feel that the organization is accessible and they like the student-dominated clientele. However, the the overall opinion about Studenthälsan’s image is quite vague and the marketing material is regarded dull and often too informational. The students are mobile and do not feel loyality toward the organization as such. Studenthälsan is in need of a clear communication platform to strengthen its profile and thus further improve its image among the students. Keywords: Studenthälsan, students, image, profile, relations.

On sandy coastlines dunes provide a barrier of protection from strong environmental forces that can naturally occur during storm events including storm surges that expose the dunes to large waves. A set of laboratory experiments were used to investigate the morphological processes during the erosion of a steep dune face under bichromatic wave conditions for two different mean water level elevations, corresponding to storm surges and waves that collide with or overwash the dune. In the collision regime, episodic slumping due to the undercutting of the dune resulted in sudden erosional events followed by long periods of wave-driven reshaping at the dune toe. In the overwash regime, dune erosion was faster and occurred at a more consistent rate. Small scale bedforms (ripples) measured during the overwash test evolved in height faster and to greater overall heights than collision test while bedform lengths were not affected by the change in water level. A numerical model, XBeach, was calibrated to examine the ability to predict erosion of the steep dune due to waves in the two water level regimes. XBeach was not able to recreate the spatial variability of the significant wave height profile from the laboratory measurements; however, mean velocities were in good agreement with observations suggesting that bed shear stress is well estimated. During mobile bed simulations of erosion in the two regimes, the model was in agreement with measured dune erosion after initial adjustment. XBeach was very sensitive to several parameters that control the rate of erosion including the critical avalanching slope under water, the threshold water depth and the sediment transport formulation. The model did not perform well at predicting erosion rates until these parameters had been modified. Overall, XBeach performed better when simulating dune erosion in the overwash regime than the collision regime. / Thesis (Master, Civil Engineering) -- Queen's University, 2014-04-01 14:54:35.257

Vykstant švietimo reformai, visas bendrasis ugdymas yra orientuotas į mokinį, jo poreikius ir gebėjimus. Mokiniui reikia prisitaikyti gyventi modernioje visuomenėje, kurioje būtina mokėti ieškoti žinių ir adekva��iai jas pritaikyti. Vienas svarbiausių uždavinių įgytas žinias pritaikyti pasirenkant profesinę veiklą. Šiandieninis pasaulis reikalauja lankstumo ir prisitaikymo. Mokiniams svarbiausia adekvačiai pasirinkti profesiją. Tam įtakos turi moksleivio aplinka: tėvai, mokytojai, bendraamžiai. Mokinių pasirengimas karjerai yra sudėtingas ugdymosi procesas. Pirmiausiai moksleiviai turi pažinti save, savo gebėjimus, polinkius. Mokykloje turi būti teikiamos profesinio informavimo, konsultavimo ir orientavimo paslaugos. Profesijos pasirinkimas yra viena aktualiausių problemų, nuo kurios tinkamo sprendimo priklauso žmogaus asmeninės gerovės augimas. Todėl labai svarbu, kad jau pats pirmasis mokinio apsisprendimas būtų sąmoningas, tikslingas, kad mokinys suprast, jog adaptacija darbo pasaulyje ir asmenybės vidinė harmonija priklauso nuo tinkamo apsisprendimo. Vykdant profesinį orientavimą bendrojo lavinimo mokyklose, turėtų būti siekiama padėti jaunimui pasirinkti mokymosi profilį, profesiją, darbinę veiklą. Profilinio mokymo esmė yra mokymosi organizavimas atsižvelgiant į moksleivių siekius, polinkius, gebėjimus, sudarant jiems galimybes pasirinkti mokymosi kryptį atitinkančius dalykus bei skirtingus jų kursus. Profiliavimo kaip ugdymo sistemos tikslas yra labiau... [toliau žr. visą tekstą] / During the process of educational reform, the whole general education is orientated towards the student, his/her needs and abilities. The student has to adapt for living in modern society , where it is necessary to know how to look for information and to use it adequately. One of the most important goals is to use the knowledge in choosing a professional career. Today’s world requires flexibility and adaptation. The most important for students is to choose the profession adequately. The whole environment influences it: parents, teachers, friends. The preparation for the future career is a complex educational process. First the students have to know themselves, their abilities and interests. The school has to give some service of professional orientation, consultation and information. Choosing a profession is one of the most important problems and how well you choose it, your future and your personal development depend. That is why it is very important that the first choice is logical, motivated and that the student will understand that the adaptation in the working world and personal harmony depend on the right decision. During the process of professional orientation at school it has to be important to help young people to choose the learning profile, profession and practical activities. The essence of profile education is to organize it having in mind students’ objectives, interests, abilities, giving them a chance to choose the subjects and courses which are... [to full text]