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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Conceptualization and design of a future chest drainage canister

Wang, Zihao January 2016 (has links)
Changsha city in Hunan province, China. Place: Changsha Center Hospital, Hunan province. City Area: 11,819 square kilometers City population: 714.66 million   I watched the whole process of chest drainage surgery, introduced by Yang Jicheng, who is a thoracic surgeon attending doctor at this capital. During the field research in China, I also had research opportunity of chest drainage management, mostly performed by nurses, where I found out lots of design opportunities about the Chong canister, which was the most popular chest drainage canister used all over the  China Then I went back to Umea, Sweden, met Fredrik Homner who is a thoracic surgery doctor working in Norrlands University Hospital for almost 30 years. I told him what I saw in China and we exchanged lots of opinion about chest drainage. I realized that Chinese chest drainage patients were suffering unnecessary pain from outmoded equipment, which in Sweden they had already updated since 20 years ago. Whit help of Fredrik Holmner, I had opportunity to watch the whole process of pulmonary resection and endoscope technical, the focus of this process was the insertion of chest drainage tube at the end of this 5 hours surgery. After I had seen so many materials related to chest drainage, I found out my design focus, which was the Maquet Oasis Drain,  that had been recognized as the most advanced chest drainage equipment in the world and had been widely used in Europe and United States.
2

Mezinárodněprávní aspekty zhroucení státu / International Legal Aspects of State Failure

Kostínek, Lukáš January 2017 (has links)
International Legal Aspects of State Failure The phenomenon of failed states is one of the great issues in our contemporary world. International public law does not take it into consideration and still, it exists. Whether the phenomenon is designated as a collapse of a state, collapse of a state authority, state failure, or as a collapsed, failed, failing state or otherwise, there is nowadays much more attention attached to it from the ranks of statesmen and representatives of international organizations. That is why I chose to deal with this issue. The content of this work is structured from the most general topic regarding this issue, which means from general definition of the term, characteristics of a failed state as a phenomenon in expert, not only legal, discussion and it's difference from similiar phenomenons towards particular aspects arising from public international law and summarization of a situation in some of real failed or failing states. In second chapter, there is a general characterization of the phenomenon itself, mostly from the factual perspective with use of mostly international law and political science literature. There is also defined, which approach has been taken regarding the issue. In third chapter, the work is dedicated purely to international law aspects of state...
3

An Investigation of Radiation Treatment Plan Quality and Time Constraints: Factors Affecting Optimization for RayStation's Collapsed Cone Algorithm

DeLuca, Enrico Donald January 2021 (has links)
No description available.
4

Comparison and Validation of RayStation Photon Monte Carlo (MC) Beam ModelVersus Collapsed Cone Convolution (CCC)

Grelle, Frederick Orin 15 June 2023 (has links)
No description available.
5

Forecasting Trajectory Data : A study by Experimentation

Kamisetty Jananni Narasimha, Shiva Sai Sri Harsha Vardhan January 2017 (has links)
Context. The advances in location-acquisition and mobile computing techniques have generated massive spatial trajectory data. Such spatial trajectory data accumulated by telecommunication operators is huge, analyzing the data with a right tool or method can uncover patterns and connections which can be used for improving telecom services. Forecasting trajectory data or predicting next location of users is one of such analysis. It can be used for producing synthetic data and also to determine the network capacity needed for a cell tower in future. Objectives. The objectives of this thesis is, Firstly, to have a new application for CWT (Collapsed Weighted Tensor) method. Secondly, to modify the CWT method to predict the location of a user. Thirdly, to provide a suitable method for the given Telenor dataset to predict the user’s location over a period of time.   Methods. The thesis work has been carried out by implementing the modified CWT method. The predicted location obtained by modified CWT cannot be determined to which time stamp it belongs as the given Telenor dataset contains missing time stamps. So, the modified CWT method is implemented in two different methods. Replacing missing values with first value in dataset. Replacing missing values with second value in dataset. These two methods are implemented and determined which method can predict the location of users with minimal error.   Results. The results are carried by assuming that the given Telenor dataset for one week will be same as that for the next week. Users are selected in a random sample and above mentioned methods are performed. Furthermore, RMSD values and computational time are calculated for each method and selected users.   Conclusion. Based on the analysis of the results, Firstly, it can be concluded that CWT method have been modified and used for predicting the user’s location for next time stamp. Secondly, the method can be extended to predict over a period of time. Finally, modified CWT method predicts location of the user with minimal error when missing values are replaced by first value in the dataset.
6

Interactions between Phytophthora cinnamomiand Acacia pulchella: consequences on ecology and epidemiology of the pathogen

A.Jayasekera@murdoch.edu.au, Arunodini Uthpalawanna Jayasekera January 2006 (has links)
Phytophthora cinnamomi is an important pathogen of many plant species in natural ecosystems and horticulture industries around the world. In Western Australia, a high proportion of native plant species are susceptible to P. cinnamomi attack. Acacia pulchella, a resistant legume species native to Western Australia has been considered as a potential biological control tool against P. cinnamomi. To develop effective control methods, it is important to understand the interactions between the control agent and the different life forms of the pathogen. In this thesis the interactions are investigated between P. cinnamomi and varieties of A. pulchella which occur in jarrah (Eucalyptus marginata) forest and sand plain ecosystems. The soil inoculum of P. cinnamomi was compared under the potted plants of the three common varieties of A. pulchella, var. pulchella, var. glaberrima and var. goadbyi. These were grown in infected jarrah forest soil in the glasshouse and in vitro in a sterilised soil-less mix aseptically. Acacia urophylla (a species non suppressive towards P. cinnamomi) was also included as a control. An isolate of the most commonly found clonal lineage of P. cinnamomi in the jarrah forest, A2 type 1 was selected for use in experiments after testing showed it reliably produced zoospores and chlamydospores both axenically and in non-sterile conditions, in comparison to several other isolates. The lowest survival of P. cinnamomi inoculum was found under A. pulchella var. goadbyi plants grown both in non sterile soil and in aseptic soil-less mix. All the life forms of P. cinnamomi were affected by A. pulchella (Chapters 2, 3, 4 and 5). The soil leachates from potted plants of A. pulchella var. goadbyi reduced sporangial production (Chapter 2) and caused cytoplasm collapse of chlamydospores (Chapter 3). The confirmation was obtained that soil under A. pulchella was inhibitory to sporangial stage of P. cinnamomi and new evidence was obtained on chlamydospore inactivation. Cytoplasm collapse in the chlamydospores was observed both for chlamydospores on mycelial discs on Mira cloth exposed to the soil leachate and within infected roots buried in soils under the three varieties of A. pulchella plants. The effect was strongest under the plants of A. pulchella var. goadbyi and indicated that the chlamydospores of P. cinnamomi are unlikely to act as persistent structures under A. pulchella var. goadbyi plants. In Chapter 4, bioassays were conducted with axenically produced mycelia, chlamydospores and zoospores to test the inhibitory effect of the root exudates collected from aseptically grown A. pulchella var. goadbyi plants. The zoospores of the same isolate used in the soil leachate tests were immobilised (became sluggish and encysted) within one to two minutes. When incubated for 24 h, zoospores predominantly clumped and germ tubes were observed only from the clumped ones. Chlamydospores produced by four isolates of the common A2 type 1 strain and the only one A2 type 2 strain available at the time were tested. A higher percentage of chlamydospores collapsed and a very low percentage germinated after 24 h. Chlamydospores of all the A2 type 1 isolates were inhibited by the root exudates whilst the A2 type 2 isolate remained viable. The findings showed that the suppressive effect must be due at least in part to substances exuded by the A. pulchella plants. However, it appeared that the A2 type 1 isolates were more vulnerable to this effect than the single A2 type 2 isolate. In Chapter 5, the effect of season on sporangial suppression of P. cinnamomi was shown using field soils collected from three jarrah forest soil vegetation types and a Banksia woodland on Bassendean sand, collected in winter and summer. The effect of age of A. pulchella plants was demonstrated using the soils collected from rehabilitated bauxite mine pits. In all the locations soils were collected under A. pulchella plants and 5 m away from the nearest A. pulchella. An effect of soil type was evident as whilst the soil leachates made from the three lateritic jarrah forest soil types where A. pulchella is common in the understorey were suppressive to the sporangial stage of P. cinnamomi, this effect was not evident in the Bassendean sand under A. pulchella. A. pulchella soils collected in winter were less suppressive towards sporangial production than soils collected in summer. An effect of plant age was demonstrated as soil leachates from four year-old A. pulchella stands in rehabilitated bauxite mine sites were more suppressive for sporangia than leachates from one year-old stands. Further information on the behaviour of the pathogen in soil and in potting mix with and without A. pulchella was obtained by infecting lupin radicles with an isolate of each A2 type, 1 and 2 strains of P. cinnamomi and burying them in the soil under the three varieties of A. pulchella plants. After a week, the chlamydospores were mostly collapsed and hyphae deteriorated. Oospores were observed and in significant numbers under the potted plants of A. pulchella var. glaberrima. Isolates of all three clonal lineages of P. cinnamomi found in Australian soil were tested for the ability to produce oospores. Two isolates of the A1 and A2 type 2 and three isolates of the common A2 type 1 were screened. The two isozyme types of the A2 clonal lineage isolated in Australia varied in ability to self and produce oospores in planta in several soils from the jarrah forest. The isozyme type 2 of the A2 clonal lineage of P. cinnamomi produced oospores under these experimental conditions. This stimulation was not effective for most of the tested isolates of the A2 type 1 and the A1 clonal lineage. The in planta oospores were viable but dormant and the oogonial-antheridial associations were amphigynous both in vitro and in vivo. For the first time it was established that, the stimulus for selfing and oospore formation in the A2 type 2 of P. cinnamomi is available in some jarrah forest soils, with and without A. pulchella and also in the potting mix used. This raises important questions for the management of the pathogen. Several factors were identified as potential stimuli for selfing. Among them, soil nutrient levels and essentially enhanced sulphur presence were found important. Temperature also played a key role. Oospores were produced abundantly at 21 – 25 ºC but not over 28 ºC. The biology of P. cinnamomi has been studied for several decades but some important aspects remain un-researched. This thesis pioneers research into the in planta selfing aspect of the pathogen in soil. It also improved the understanding of the interactions between P. cinnamomi and A. pulchella which to some extent supports use of A. pulchella as a biological control tool against P. cinnamomi. However, attention is drawn to the natural mechanisms of this complex pathogen to survive in planta by producing oospores, the most persistent form of its life cycle.
7

震災時学区避難者数及び救難物資の推定に関する研究

邵, 俊豪 23 January 2012 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第16506号 / 工博第3499号 / 新制||工||1529(附属図書館) / 29163 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 田中 哮義, 教授 田中 仁史, 教授 神吉 紀世子 / 学位規則第4条第1項該当
8

Investigation of a Collapsed Cone Superposition Algorithm for dosimetry in brachytherapy

Alpsten, Freja January 2021 (has links)
Background & Purpose: The current standard dosimetry in brachytherapy treatment planning, the TG-43 formalism, ignore the presence of non-water media and finite patient dimensions. This can cause clinically relevant errors in dose estimates. To over- come the limitations of the TG-43 formalism, Model-Based Dose Calculation Algorithms (MBDCAs) have evolved. One of the commercial available MBDCAs is the Advanced Collapsed cone Engine (ACE) by Elekta. In ACE, the total dose is divided into three components, the primary, the first-scattered and the multiple-scattered dose, where the two last mentioned are calculated by the means of the Collapsed Cone Algorithm. In this study the performance of ACE has been investigated. The study has been di- vided into 2 parts, where the aim of part 1 was to analyze the relationship between the so called discretization artifacts, caused by the collapsed cone approximation, and the number of dwell positions. The severeness of the artifact is thought to decrease as the number of dwell positions are increased. The second part focus on ACE’s behavior in cortical bone, with the aim to form a hypothesis (explanation and solution) to the previously observed dose underestimation of the dose to bone made by ACE. Materials and Methods: The generic 192Ir source, the Oncentra Brachy (OcB) treatment planning system (TPS) and the Monte Carlo (MC) platform ALGEBRA have been utilized. In the first part of the study, six source configurations, all with a different number of dwell positions, were created and placed in the center of large water phantoms, i.e. under TG-43 conditions in which the TG-43 formalism can be assumed to yield a high accuracy of the estimated dose. The accuracy of ACE has been judged by its’ deviation from TG-43. In the second part of the study, a cubic source configuration, of 27 dwell positions, was positioned at the center of a cubic water phantom. Three cases where constructed, with a small cortical bone heterogeneity positioned at different distances from the source configu- ration. The ACE calculated dose distribution has been divided into its’ three constituents. The accuracy of ACE and TG-43 has been judged by its’ deviation from MC. Results: Part 1 showed that increasing the number of dwell positions does not guar- antee an improved accuracy of ACE. Local dose difference ratios of > 2%, caused by the artifacts, were mainly located outside the 5% isodose line. A general dose underestima- tion was observed in ACE, with an increased magnitude as the dose level decreased. The majority of local dose difference ratios below -4% were found where the multi-resolution voxelization grid of ACE has a voxel size of ≥23 mm3, that is at a distance of ≥8 cm from the closest dwell position when using the ACE standard accuracy level. In part 2, ACE underestimated the dose to cortical bone, with an increased magnitude as the bone was positioned farther away from the source configuration. The TG-43 formalism gave slightly better estimates of the mean dose to bone than ACE, especially at higher dose levels. For a mean dose to the cortical bone heterogeneity equal to 45% of the prescribed dose, TG-43 and ACE underestimated the mean dose with 1% and 4%, respectively. The estimated mean dose to a volume located directly behind the heterogeneity agreed within 1% between ACE and MC. However, an increased amount of positive local dose difference ratios were observed in this volume. Conclusions: Increasing the number of dwell positions cause a ”blurring” effect of the artifact, but may also increase the fluence gradient. In such situations the severeness of the artifact may not be improved. In patient cases the dwell positions are usually added in a more random manner which may favor the ”blurring effect”. The underestimations observed in ACE are thought to be caused by both the multiple- resolution voxelization grid of ACE and the relationship between the dimensions of the phantom in which the multiple-scattered kernel has been generated and the current calcu- lation volume. ACE was unsuccessful to predict the dose to cortical bone, and should hence be used with caution when cortical bone is an organ at risk, as long as the problem remains. The results indicates that the error in ACE is located in the scatter dose calculations and that the heterogeneity cause ACE to displace the dose. The error is thought to be located in the multiple-scattered dose component, which was also shown by Terribilni et al.. A hypothesis is that the problem is caused by the neglected effect of media dependent absorption coefficients in the multiple-scattered dose calculation. A suggested solution, left to be proven, is to use effective attenuation scaling factors.
9

Typologie weak, fragile, failing, failed states, collapsed states / Typology of weak, fragile, failing, failed states, collapsed states

Janků, Kateřina January 2013 (has links)
Diploma thesis called "Typology of weak, fragile, failing, failed, collapsed states" lays the objective to look into all kinds of collapsed states, and then it wants to compare to what measurement answers the specified typological conception to the reality. In the introduction the study attends to definitions of the terms state,sovereignty and nation which are nearly connected with the issue. As well the reasons for geographical enlistment will be given at the same time. The first chapter is focused on the characteristic features of the different types of watched states. That is why the comparison of the terms is included, its objective is specification and coherence of the terminology. The next part will be engaged in the application of chosen marks to the concrete African countries. There is simultaneously offered the answer to question, in what way and to what measurement the theoretical conception differ from the real functioning. And then it is seen if the enlistment of countries agrees with their general situation, and there are eventually watched some reasons if it does not agree. The last but one chapter is focused on the critical review of the whole typology of collapsed states and it mediates a wide range of aspects and findings which are brought by the typology. The end provides some...
10

Type-1 Active Falactic Nuclei and their Supernovae

Imaz Chacon, Inigo January 2019 (has links)
Supernovae (SNe) and more specifically Core-Collapsed SNe (CC SNe) are signatures of on-going star formation (SF), and higher star formation rates. In this project, we perform a study of all SNe ever discovered inside a specific type of galaxy: a type-1 Active Galactic Nucleus (AGN1). We calculate the SN detection fraction for CC SNe and thermonuclear SNe in AGN1. In AGN1, inclination of the host galaxy and the radial distance of the SN to the center of the galaxy are displayed. As a second goal, we gather all SNe from the OpenSN catalogue found close to an AGN1, classify them and compare them with the full sample of OpenSN catalogue host galaxies. Results:We found and calculated the SN detection fraction of AGN1s. We found 16 SNe exploding in 13 different AGN1 host galaxies. The CC/Ia SN ratio is ~ 0.78. Comparing by similar morphology, the AGN1-host galaxies with all the host galaxies from OpenSN, we see that the detection fractions are higher in spiral AGN1 hosts than in normal spiral galaxies, but the difference is not significant (~ 0.4\sigma) to be considered.

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