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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.
31

Uma arquitetura para combinação de classificadores otimizada por métodos de poda com aplicação em credit scoring

Silva Filho, Luiz Vieira e 17 February 2014 (has links)
Submitted by Lucelia Lucena (lucelia.lucena@ufpe.br) on 2015-03-09T19:29:39Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO Luíz Vieira e Silva Filho.pdf: 2176053 bytes, checksum: 4882a96e67804421bca22e07debc49da (MD5) / Made available in DSpace on 2015-03-09T19:29:39Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO Luíz Vieira e Silva Filho.pdf: 2176053 bytes, checksum: 4882a96e67804421bca22e07debc49da (MD5) Previous issue date: 2014-02-17 / Sistemas de Múltiplos Classificadores (Multiple Classifiers Systems - MCS) se baseiam na ideia de que combinar a opinião de vários especialistas pode produzir melhores resultados do que quando se usa apenas um especialista. Diversas técnicas de MCS foram desenvolvidas, apresentando pontos fortes e fracos, a depender do contexto em que são aplicadas. Este trabalho propõe uma arquitetura para MCS que visa potencializar a complementaridade entre essas técnicas, possuindo dois objetivos principais: i) a combinação de métodos de amostragem tradicionais, visando a geração de classificadores de melhor desempenho que componham um pool de classificadores; ii) a aplicação de um algoritmo de poda para remover do pool aqueles classificadores incompetentes para lidar com o problema em questão, considerando os critérios de seleção adotados. A arquitetura proposta foi avaliada em uma aplicação de credit-scoring. Os métodos de amostragem usados foram o Bagging e o Random Subspace com classificadores-base sendo árvores-de-decisão, construídas com base no algoritmo CART. Para o processamento da poda foi usado o algoritmo Orientation Ordering, e para combinação das saídas dos classificadores do ensemble adotou-se o método Majority Vote. Os experimentos realizados mostraram que a arquitetura proposta alcançou taxas de acerto similares ou superiores às atingidas pelos métodos apresentados na literatura. Esses resultados ainda foram obtidos com ensembles cujos tamanhos eram da ordemde 20% dos pools originais gerados na fase de treinamento.
32

Management control systems (MCS) in the small business context:linking effects of contextual factors with MCS and financial performance of small firms

Jänkälä, S. (Sinikka) 14 August 2007 (has links)
Abstract Small businesses are numerous in any country. However, we have very limited knowledge regarding their management accounting (MA) and management control systems (MCS). Traditionally, it has been stated that small firms do not need and use MCS due to their simple structures and poor resources. On the other hand, a few studies on high technology firms have shown that these firms have developed their MCS and are also utilizing sophisticated management accounting practices and information. The aim of this study is to analyse small firms' use of MCS practices as well as to examine the role of MCS practices and information of small firms in a contingency theoretical framework. Furthermore, the study is not only focusing on small, rapidly growing firms but also on traditional, more stable small firms, all employing from 10 to 49 persons. Based on the survey responses of 183 managing directors of small Finnish firms, the study describes the diffusion and penetration of MCS practices and information among small firms. Two theoretical models are constructed linking the use of MCS with strategy, perceived environmental uncertainty (PEU), use of diversified management team and financial performance of small firms. Tests are made by using structural equation modeling (SEM). The results suggest that small firms do use a wide range of MCS practices and information. The main results also indicate that the use of a more diversified management team seems to increase the use of MCS practices and information. The use of more advanced practices is related to small firms which have been more profitable or which have had lower growth rates in sales. In addition, the use of MCS seems to be associated with small firms' strategies, both realized and intended. The pursued strategy seems to drive small firms' profitability and growth in net sales. However, such an association was not found between the intended strategy and financial performance after two years. The use of MCS seems to have only a few positive effects on small firm's financial performance. Nevertheless, more use of advanced dimensions of MCS seems to predict significant improvements for longer-term growth in net sales.
33

Three factor Prothrombin Complex Concentrate to Reverse Warfarin Treated Mechanical Circulatory Device Patients Immediately Prior to Heart Transplant

Sears, Bryan, Cosgrove, Richard January 2015 (has links)
Class of 2015 Abstract / Objectives: To determine if using three-factor prothrombin complex concentrate (PCC) immediately prior to heart transplantation reduces blood product transfusions in patients bridged to heart transplantation by mechanical circulatory support (MCS) devices who are treated with warfarin. Methods: This study retrospectively reviewed patients that either received PCC or received usual care (i.e. fresh frozen plasma – FFP) prior to heart transplantation. Outcomes that were evaluated included packed red blood cell (RBC), FFP, platelet and cryoprecipitate transfusions intra and five days post-operatively, Cell Saver autologous blood volume administered intra-operatively, chest tube output for the five days post-operatively, and thromboembolic events post-operatively. Results: There were 24 patients included in the study, 12 from each group. The PCC group showed significantly less intra-operative RBC transfusion (2.60 ± 1.49 units vs. 5.09 ± 2.42 units, p=0.018), Cell Saver autologous blood usage (2.60 ± 1.49 units vs. 4.02 ± 1.55 units, p=0.032), and FFP transfusion (2.14 ± 2.30 units vs. 10.94 ± 5.96 units, p=0.0005) than the usual care group. There was no difference in amount of vitamin K given, change in INR, platelets administered, cryoprecipitate administered, chest tube output, or thromboembolic events between the groups. The average dose of PCC was 31 units/kg IV; repeat doses were given to 2 patients. Conclusions: We propose that the use of PCC prior to heart transplant surgery for patients on MCS devices anticoagulated with warfarin may result in the reduction for the need of RBC’s, autologous blood use and FFP during surgery.
34

Developing a Framework for Management Control Systems in Start-ups : How Management Control Systems can be used in fast-growing technology start-ups to support controlled growth

Lundell, Tobias, Forzelius, Magnus January 2017 (has links)
The purpose of this study was to find what appropriate Management Control Systems exist that can help fast-growing start-ups to achieve a controlled and healthy growth. We also studied how the control systems can be used together, and balanced between each other. To find appropriate control systems, we conducted a literature review of important factors for implementing management control, that ended with a tentative framework of control systems. After that, we conducted a multiple case study including several fast-growing technology start-ups to see how they use the collection of control systems in our tentative control framework, and analyzed what effect they have on the organization’s activities and how they balance between them. After the case study, a cross-case analysis was conducted were differences and similarities between the cases were analyzed and related to the theoretical concepts from the literature review. This led to conclusions regarding how start-ups tend to use and balance the control systems, which in turn led to the finalized control framework for fast-growing start-ups. The framework provides a set of control systems that start-ups can use that are relevant for supporting growth and managing the most common challenges that fast-growing start-ups face. By using different levers of control, the control systems complement each other and create a dynamic tension, which increases performance. For start-ups that are in a product development phase, the balance of the control systems is mostly on growth and innovation, which supports exploration of opportunities. However, there is still a little focus on control and efficiency to keep the organization focused. For start-ups with an already developed and commercialized product, the balance of control systems is more towards the middle. The most focus is put on growth and efficiency, with a little less emphasis on innovation and control. This is a way to keep an even balance between exploration of opportunities and exploitation of current resources.
35

Development of Lipid-based Nano Formulations of Miriplatin Against Lung Cancer

Xu, Zizhao 01 January 2020 (has links)
Cancer is the second leading cause of death and is responsible for approximately 9.6 million deaths worldwide in 2018. Among all oncological diseases, lung cancer claims the highest mortality (male: 23.5%; female: 22%) and the second most new cases (male: 13%; female: 12%) in the US. Approximately 40% of newly diagnosed lung cancer patients are in the advanced stage IV, for which platinum-based chemotherapy is the first-line treatment, either by itself or in combination with surgery or radiotherapy. Cisplatin, the first-generation platinum-based anticancer chemotherapeutic agent, has the highest potency against lung cancer but carries many severe adverse effects. Cisplatin also induces drug resistance during long-term chemotherapy. Many more platinum complexes have been investigated as better alternatives, which led to the approval of carboplatin and oxaliplatin by Food and Drug Administration (FDA). In addition, miriplatin suspended in iodolipds (lipiodolization) was approved in Japan for the treatment of hepatocellular carcinoma (HCC) in 2009. Miriplatin has the same non-leaving group as oxaliplatin but different leaving groups of two myristate chains, which make it highly lipophilic. Several characteristics of solid tumors in lung cancer constitute a physiochemical barrier to the homogenous distribution and deep penetration of chemotherapy agents. Nanocarriers provide a promising platform to overcome the physiochemical barrier and to reduce the systemic toxicity of anticancer chemotherapy. In this study, miriplatin is formulated with various lipid-based nanocarriers including micelles and solid lipid nanoparticles (SLNs) thanks to its highly lipophilic structure. The goal of this thesis is to develop and evaluate miriplatin-loaded nano formulations against lung cancer. Miriplatin-loaded formulations were prepared by different methods, including thin film hydration and several scale-up methods including chloroform dripping, chloroform injection, chloroform evaporation, co-solvent evaporation, chloroform slow evaporation and co-solvent slow evaporation. Between the two types of nano formulations under this study, micelles were much smaller (~10 nm in diameter) and more homogeneous (PDI < 0.3), while SLNs were bigger (~ 100 nm in diameter) and more heterogeneous (PDI ~0.8). A quantification method of miriplatin was established using inductively coupled plasma-optical emission spectrometry (ICP-OES). The quantification of platinum recovery from different miriplatin-loaded nano formulations was facilitated by digestion with 70% nitric acid and heating. The co-solvent slow evaporation method to prepare miriplatin-loaded nano formulations improved the platinum recovery prominently from 10% to 70%. Thus, co-solvent slow evaporation has been established as a pharmaceutically viable scale-up method to prepare nano formulations of miriplatin. Miriplatin-loaded nano formulations of different compositions were negatively stained with uranyl acetate and then imaged by transmission electron microscopy (TEM), which showed the formulations’ size and morphology that were consistent with the size and PDI data from dynamic light scattering studies by the Malvern Zetasizer. In the TEM studies, micelles showed a morphology of spherical dots at around 10 nm in diameter while SLNs showed both spherical and rod structures with a size distribution from 50 to 150 nm. A three-dimensional multicellular spheroid (3D MCS) model of A549-iRFP cells was used for in vitro evaluation of the nano formulations’ activity against lung cancer. A549-iRFP cells were engineered from the common lung cancer cell line A549 to stably express the near-infrared fluorescent protein (iRFP). The viability of A549-iRFP 3D MCS after exposure to cisplatin or nano formulations was similar to A549 3D MCS. The anticancer activity of miriplatin-loaded nano formulations against 3D MCS was positively associated with the platinum recovery as quantified by ICP-OES. The miriplatin-loaded nano formulations that had been prepared by the co-solvent slow evaporation method showed substantial anticancer activities against A549 3D MCS and A549-iRFP 3D MCS, which were comparable to cisplatin. Taken together, miriplatin-loaded nano formulations were successfully prepared by co-solvent slow evaporation. The formulations were developed to carry favorable physiochemical properties to enhance the activities of platinum drugs against lung cancer.
36

Managing Corporate Social Responsibility with Management Control Systems

Issah, Fadilatu January 2020 (has links)
Purpose- This study aims to explore how management control systems are used to manage their corporate social responsibility strategies in organizations. This paper dives into how sustainability managers use existing controls in planning, executing, measuring, and reporting on their CSR. The challenges they face in implementing their CSR strategies with these control systems are also covered.  Methodology- The research was conducted using a qualitative research approach and a multiple case study strategy. The multiple case study involved three companies within a CSR network in Sweden. Secondary data from sustainability reports, internal financial control (IFC) reports were used together with seven semi-structured interviews.  Findings- Control systems monitor influence and steer the employee's behavior and actions towards achieving organizational goals. The thesis provides practical insights into how sustainability managers from the studied companies use management control systems. The findings indicate that companies use similar clusters of management controls in planning, executing, measuring and reporting on their corporate social responsibility. However, there are differences in how the same management controls are used. The author identified a different type of control which is mostly not included in discussing when discussing MCS.
37

Vägen Framåt : En fallstudie om hur ett företag använder sin ekonomistyrning för att arbeta mot hållbarhet

Zubenko, Viktoria, Olsson, Madelene January 2023 (has links)
Syftet med denna studie är att undersöka hur ett företag använder ekonomistyrning för att bidra till ekonomisk, social och miljömässig hållbarhet. Studien baseras på en analysmodell kallad Management Control System (MCS), som utgår från teoretiska ramverk inom ekonomistyrningssystemet och särskilt främjar ekonomisk hållbarhet. För att undersöka företagets arbete med sociala och miljömässiga aspekter tillämpas alla dessa dimensioner på MCS. I en kvalitativ fallstudie av företaget Hedern Fastigheter genomfördes semistrukturerade intervjuer med anställda från olika arbetsområden. Resultaten visar att företaget använder sina styrverktyg på olika sätt för att främja olika aspekter av hållbarhet. Slutsatser dras kring att miljömässiga dimensionen inom verksamheten ges mindre fokus än de finansiella och sociala dimensionerna på grund av implementeringsmognad och prioritering av ekonomisk lönsamhet, vilket resulterar i minskad belysning av vissa hållbarhetsaspekter. Studien visar att varje hållbarhetsdimension erhåller olika uppmärksamhet beroende på hur integrerade de anses vara i styrverktygen. Slutligen framkommer det att ekonomisk lönsamhet är central i verksamheten men ger upphov till vissa indirekta sociala och miljömässiga hållbarheter.
38

midazole-based pH-sensitive Convertible Liposomes for Anticancer Drug Delivery

Huang, Ruiqi 01 January 2020 (has links) (PDF)
Solid tumors possess biological features that are different from those in healthy tissues, which provides opportunities of anticancer treatment by nanomedicines. Due to the presence of the fenestrated tumor vasculatures, nanomedicines can selectively accumulate in tumor tissues by the enhanced permeability and retention (EPR) effect. The acidic pH in tumor interstitium (pH 6.0-7.0) also provides a promising mechanism to trigger the nanomedicines to promote the cellular uptake of cargo drugs. The previously reported stealth liposomes coated with PEG are known to accumulate in tumors owing to their prolonged circulation time. The PEG coating on liposomes can hinder serum protein adsorption and thus prevent rapid elimination by the reticuloendothelial system, thus increasing the liposome circulation time. However, liposomal interaction with cancer cells can also be hindered by the PEG coating. In order to improve the anticancer activity of stealth liposomes, novel synthetic imidazole-based lipids were introduced to the composition of stealth liposomes to develop the pH-sensitive imidazole-based convertible liposomes (ICL). At acidic pH, the imidazole-based lipids would protonate to acquire positive charges, thus clustering with the negatively charged PEGylated lipids. Such lipid-lipid electrostatic interaction would induce phase separation of the bilayer to generate a PEG-free domain that displays excess positive charges. Such newly converted, cationic liposomes at acidic pH in tumor interstitium would have better interaction with negatively charged cancer cells and/or enhanced drug release, therefore overcoming the drawback of traditional stealth liposomes. After synthesizing the imidazole-based lipids DHI, DHMI and DHDMI, we constructed doxorubicin (DOX)-loaded ICL formulations. The physicochemical properties of ICL were characterized, and factors influencing such properties were explored. The pH-triggered acquisition of positive charges of ICL was confirmed by the elevation of ζ- potentials and aggregation with negatively charged model liposomes that mimic bio-membranes at acidic pH 6.0-7.0. Acidic pH-triggered release of ICL was confirmed by drug release assays. It was also found that although the incorporation of cholesterol can remarkably reduce the size and increase the encapsulation efficiency (EE) of ICL, it also hinders the pH-sensitivity of ICL. The morphology of ICL at both pH 7.4 and pH 6.0 was characterized under transmission electron microscopy (TEM), which showed morphological changes in response to acidic pH 6.0, which further supported the proposed pH-sensitivity of ICL. Cytotoxicity assays on 3D MCS of HeLa, A549, MDA-MB-231 and MDA-MB-468 cell lines were conducted to evaluate the anticancer activity of ICL formulations. ICL formulations without cholesterol showed considerably enhanced anticancer activities against MCS compared with the non-sensitive stealth liposomes (NSL). However, incorporation of cholesterol decreased such activities. The IC50 values of cholesterol-free ICL and ICL with cholesterol against MCS strongly suggested that the pH-sensitivity introduced by the imidazole-based lipids would enhance the anticancer activity of stealth liposomes, while the hindrance of the pH-sensitivity by cholesterol would reduce such activities. Taken together, ICL’s pH-sensitivity is correlated with their enhanced anticancer activity than non-sensitive stealth liposomes.
39

Helelektriska tunga lastbilar: En studie om påverkan på elnätet

Ali, Roni January 2023 (has links)
Sweden has ambitious climate goals, such as the overarching goal, the 2045 goal. The goal is for Sweden to have zero net emissions of greenhouse gases by 2045 at the latest. In order to achieve the overall climate goal and the interim targets, electrification of society is an important component. The industrial sector and the transport sector each account for about a third of Sweden’s emissions, where the conversion to electricity is an important solution. The electrification of passenger cars and buses has meant that emissions from domestic transport have decreased every year, and in order to achieve the interim target of 70 percent lower emissions of greenhouse gases in 2030 compared to 2010, the electrification of heavy duty trucks is one of the key components. However, there are long-term challenges with the power grid and already today grid owners have capacity challenges. Regional grid owners cannot increase their power subscription, while local grid owners cannot grant new connections. Regarding the electrification of long-haul transportation, there are challenges in terms of charging infrastructure. Truck drivers operate on a strict schedule, and minimizing down time is crucial to keep costs down. By law, truck drivers must take a 45-minute break after 4.5 hours of driving time, which means that during this break it is desirable to recharge the vehicle before departure. This means that high power demands are placed on the charging infrastructure that exists to be able to transmit the desired energy.   A new standard, the Megawatt Charging System (MCS), which meets the high power requirements has been developed and is included in pilot projects. The maximum power that the charging standard can deliver is 3.75 MW. The results of the thesis show that these high-power chargers place high demands on thepower grid. When connecting a charging station with MCS charging points to the grid, it may require local upgrading of lines and transformers, but also upgrading in otherparts of the network. Examples of such upgrades are reactive power compensation to be able to support the network locally at peak loads to obtain voltage levels within stable voltage ranges, but also upgrades of lines and transformers to be able to deliver the desired power. Integration of a battery storage in connection with a charging station relieves the powergrid and its components. However, it is important to highlight that since the battery needs to be recharged, this means that a more even power requirement is needed. However, the  maximum load on both transformers and lines is reduced, which can be a desirable effect when a charging station of the same nature is put into operation.
40

Dynamique intertemporelle et équilibre général calculable : Une application à l'accord de partenariat économique entre l'Union européenne et le Ghana / Intemporal dynamic and computable general equilibrium : an application to the economic partnership between the Europena Union and Ghana

Philip, Jean-Marc 21 December 2011 (has links)
L’objectif de la thèse est d’identifier la pertinence des modèles en équilibre général calculable (MEGC) pour analyser la problématique posée par les Accords de Partenariat Économique (APE) entre l’Union européenne et les pays ACP. Une revue de la littérature est d’abord réalisée, puis un modèle en équilibre général calculable (MEGC) à dynamique intertemporelle est construit pour analyser l’impact de l’APE sur un pays spécifique : le Ghana. À partir du constat portant sur la diversité des résultats de simulations, qui dépendent essentiellement de la structure du modèle et des modes de fermeture choisis par le modélisateur, ce travail cherche à mettre en évidence la largeur du faisceau de résultats possibles et l’impossibilité de mettre en avant les bénéfices potentiels qui peuvent être attendus d’un tel accord en s’appuyant simplement sur des MEGC néoclassiques standards. / This work aims to analyze to what extent the use of an applied general equilibrium model (AGE) allows to correctly assess the potential economic impact of EPAs between ACP countries and the European Union. First, a review of the literature is conducted and then an intertemporal dynamic AGE model is built in order to assess the potential impact of EPA on a specific country: Ghana. From the variety of results resulting from the models simulations and depending on hypothesis made on the model structure and the type of closure chosen by the modeler, our work aims to stress the risk of using standard neoclassical Walrasian models to assess the potential benefits of an EPA on ACP countries economy.

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