Investigation of a medium-sized floating offshore wind turbine with stall regulation

The thesis begins with the development of a stall control concept for a variable-speed medium-sized floating offshore wind turbine. Firstly, the control and protection concepts were developed to ensure the highest possible efficiency throughout the operation. Secondly, fully integrated aero-hydro-servo-elastic simulations were performed to characterize the global dynamic response of the system, identify the design driving loads, and highlight the impacts brought about by the floating support structure

Data to the earthworm fauna of Myanmar with notes on some little known species (Annelida, Oligochaeta)

The earthworm fauna of the Republic of the Union of Myanmar (Burma) is quite well studied due to the studious works of Gordon E. Gates. However, after the publication of the comprehensive monograph Burmese earthworms (Gates 1972) there has been no new data published from this country. In the last year the last author collected several earthworm samples from Burma, resulting in 7 species records belonging to the families Moniligastridae, Benhamiidae, Octochaetidae and Megascolecidae including some little known species like Tonoscolex depressus (Gates, 1929) and Eutyphoeus constrictus Gates, 1929. Examination of the E. constrictus specimens revealed that they show different states of metandry, they are morphologically very similar to E. hastatus Gates, 1929, and only differ by the functionality of the testes in segment 10, therefore it should be regarded as a synonym of E. constrictus

A Modified Hierarchical Agglomerative Approach for Efficient Document Clustering System

In today’s world, the increasing volume of text documents has brought challenges for their effective and efficient organization. This has led to an enormous demand for efficient tools that turn data into valuable knowledge. One of the techniques that can play an important role towards the achievement of this objective is document clustering. The main function of document clustering is automatic grouping of documents so that the documents within a cluster are very similar, but dissimilar to the documents in other clusters. This research proposes a Modified Agglomerative Hierarchical Clustering (MAHC) algorithm based on hierarchical method. In many traditional systems, the number of term frequency is considered to create data representation matrix. However, a modified algorithm creates data representation matrix based only on occurrence of items, not on frequency of items. The proposed algorithm can increase the quality of clustering because it can merge the related or similar documents into the same cluster efficiently. Moreover, the proposed algorithm can reduce the processing time than the existing methods. In this paper, the performance of clustering between the proposed and original clustering algorithm was compared and evaluated by using F-measure

Improving the Effectiveness of Information Retrieval System

With the rapid growth of information and easy access of information, in particular the boom of the World Wide Web, the problem of finding useful information and knowledge becomes one of the most important topics in information and computer science. Information Retrieval (IR) systems, also called text retrieval systems, facilitate users to retrieve information which is relevant or close to their information needs. This research provides an effective IR system for retrieving not only relevant but also related documents. For retrieving relevant documents, Probabilistic Model is applied. For retrieving related documents, the related indexed table is built including extracted keywords and related documents lists. In constructing related index table in the database, Shannon’s entropy difference between intrinsic and extrinsic mode is used to extract the highly significant keywords.  Entropy threshold value was assigned to 0.5 of normalized entropy difference square ( ) according to the analytical results. The proposed keyword similarity distance (KSD) function is used to calculate similarity and relations between document pair.  The proposed system is implemented by using PHP programming language and MySQL database. The performance of this approach is evaluated by using standard IR metric such as Precision (P), Recall (R), F-measure (F) and Average Precision (AP) on three test datasets (Oshumed, CISI and CRAN). According to the experimental results, the performance of the proposed system using related index table is more effective than the traditional probabilistic model

Performance Comparison of Collaborative Filtering Prediction Methods on Recommendation System

Recommendation systems were introduced as the computer-based intelligent techniques to deal with the problem of information overload. Collaborative filtering is a simple recommendation algorithm that executes the similarity (neighborhoods) between items and then computes the missing data predictions. A serious limitation of collaborative filtering is the sparisity problem, referring to the situation where insufficient rating history is available for inferring reliable similarities. This research compares four prediction methods: Weighted Sum, Mean-Centering, Boosted Weighted Sum and Boosted Double Means Centering predictions. Boosting double means centering taken into account information of both users and items in order to overcome the potential decrease of accuracy due to sparsity when predicting the missing value. It tries to capture the user and item biases from the whole effects so as to enable the better concentrating on user-item interaction. Furthermore, ensemble learning will improve the performance collaborative filtering method because an ensemble of collaborative filtering models based on a single collaborative filtering algorithm considered the problem of sparsity, recommender error rate and sample weight update. Rating history in Book-Crossing dataset with 91% sparsity level is used to evaluate the missing rating predictions and the performance comparison of rating predictions on two traditional collaborative filtering and two boosting collaborative filtering frameworks. Experimental results shows that the proposed boosted double mean centering framework improve the prediction accuracy than the two traditional collaborative filtering and the other boosting prediction algorithm

Evaluation of optimal lysine level in Myanmar local breed and DYL crossed breed pig

 A Completely Randomized Design (CRD) was comprised 2x3 factorial arrangements of two breeds (DYL and local breed) and three different lysine levels. The 12 weeks old, nine castrated DYL and nine castrated local breed were randomly allocated in each individual pen to six treatment groups with three replicates into 18 pens. Two breeds of pigs (DYL and local breed) were exposed to the three different dietary treatments, L1- basal diet without lysine supplementation, L2- basal diet with 1.15% total lysine for grower and L3- basal diet with 1.65% total lysine for grower. The growth performance and feed intake were determined for growing pigs. In this study, no significant difference (p>0.05) was found in feed intake among the three different treatments. However, significantly better body weight, weight gain and feed conversion ratio (FCR) were observed in pigs fed L2 and L3 but were not significantly (p>0.05) differ from each other. Otherwise, diets without lysine supplementation (L1) showed no better effect on the growth performances of both DYL and local breeds. It could be noted that L2 was the best level to obtain optimal growth performances and farm efficiency. Between the two breeds, body weight of DYL was superior over that of local breed. The interactions were observed between lysine levels and different breeds regard for body weight and cumulative weight gain. To wrap up, it was noticeable that crystalline lysine supplementation helped to improve growth performance in both breeds

Self-assembled nanorods in YBCO matrix : a computational study of their effects on critical current anisotropy

In order to understand how the doping with self-assembled nanorods of different sizes and concentrations as well as applied magnetic fields affect the critical current anisotropy in YBa2Cu3O7-x (YBCO) thin films close to YBCO c-axis, we present an extensive and systematic computational study done by molecular dynamics simulation. The simulations are also used to understand experimentally measured J(c)(theta) curves for BaHfO3, BaZrO3 and BaSnO3 doped YBCO thin films with the help of nanorod parameters obtained from transmission electron microscopy measurements. Our simulations reveal that the relation between applied and matching field plays a crucial role in the formation of J(c)(theta)-peak around YBCO c-axis (c-peak) due to vortex-vortex interactions. We also find how different concentrations of different size nanorods effect the shape of the c-peak and explain how different features, such as double c-peak structures, arise. In addition to this, we have quantitatively explained that, even in an ideal superconductor, the overdoping of nanorods results in decrease of the critical current. Our results can be widely used to understand and predict the critical current anisotropy of YBCO thin films to improve and develop new pinscapes for various transport applications

A Study of the Prayers and Curses as Contained in the Bagan Inscriptions

Prayers and curses are expression of emotions that comes to human's feeling. Prayers and curses come from love and anger. The Bagan inscriptions which include prayers and curses will be extracted from Ancient Burmese inscriptions Volume I, II and III. There will be an analysis of the meaning of prayers and swearings according to their categories. The purpose of this paper is to know the curses and prayers and to avoid doing evil deeds, and to do good deeds after knowing them. Although there is no prayer and swearing according to the Theravada Buddhism, prayer and swearing occurs according to the belief of the fruit of Kamma. This will be presented in this paper

The effect of lysine supplementation on the performance of Myanmar local breed and DYL crossed breed pig

A Completely Randomized Design (CRD) was comprised 2x3 factorial arrangements of two breeds (DYL and local breed) and three different lysine levels. The 18 weeks old, nine castrated DYL and nine local breed were randomly allocated in each individual pen to six treatment groups with three replicates into 18 pens. Two breeds of pigs (DYL and local breed) were exposed to the three different dietary treatments, L1- basal diet without lysine supplementation, L2- basal diet with 0.95% total lysine for finisher and L3- basal diet with 1.45% total lysine for finisher. The growth performance and back fat thickness were determined for finishing pigs. Significantly better body weight, weight gain, feed conversion ratio (FCR) and lower back fat were observed in pigs fed L2 but did not significantly differ from those fed L3. Otherwise, diets without lysine supplementation (L1) showed no better effect on the growth performances of both DYL and local breeds. It could be noted that L2 was the best level to obtain optimal growth performances and feed efficiency. Between the two breeds, growth performances of DYL were superior over that of local breed. Back fat thicknesses of DYL were also thinner than that of local breed. The interactions were observed between lysine levels and different breeds regard for final body weight, cumulative gain and feed conversion ratio. It was noticeable that lysine supplementation helped to improve growth performance and reduce back fat thickness of both local breed and DYL crossed breed. The result also showed that a comparison of the two different breed revealed the improved performances in DYL crossed breed rather than that of local breed. &nbsp

Role of the Deposition Distance on Nanorod Growth and Flux Pinning in BaZrO3-Doped YBa2Cu3O6+x Thin Films: Implications for Superconducting Tapes

A complex deposition process of high-temperature superconducting (HTS) thin films and coated conductors is usually optimized by concentrating on the crystalline quality of the material, thus getting the best possible critical temperature and self-field properties. However, most of the HTS power applications that are based on coated conductors act at high magnetic fields, and thus an alternative approach focusing on the formation of an optimal network of columnar flux pinning centers is more reasonable. Therefore, we systematically show how a lengthening of the deposition distance produces perfectly aligned and distinctly longer self-assembled BaZrO3 (BZO) nanorods within the YBa2Cu3O6+x (YBCO) matrix. This method unambiguously enhances in-field properties such as pinning force, critical current density, and its isotropy along the YBCO c axis. The experimental results, especially formation of the c peak where the relative length of the nanorod is a key issue, are confirmed by the vortex dynamics simulations. Finally, we present a semiquantitative model governing the formation of nanorods that explains the experimentally observed improved nanorod growth as a function of the deposition distance via the associated variation of the fractional partial pressure between atomic species within the laser plume. </p