924 resultados para Calculation tool in reliability
Resumo:
Floods are one of the most dangerous and common disasters worldwide, and these disasters are closely linked to the geography of the affected area. As a result, several papers in the academic field of humanitarian logistics have incorporated the use of Geographical Information Systems (GIS) for disaster management. However, most of the contributions in the literature are using these systems for network analysis and display, with just a few papers exploiting the capabilities of GIS to improve planning and preparedness. To show the capabilities of GIS for disaster management, this paper uses raster GIS to analyse potential flooding scenarios and provide input to an optimisation model. The combination is applied to two real-world floods in Mexico to evaluate the value of incorporating GIS for disaster planning. The results provide evidence that including GIS analysis for a decision-making tool in disaster management can improve the outcome of disaster operations by reducing the number of facilities used at risk of flooding. Empirical results imply the importance of the integration of advanced remote sensing images and GIS for future systems in humanitarian logistics.
Resumo:
Grandfathering is currently the main principle for the initial allocation of tradable CO2 emission rights under the European cap-and-trade scheme. Furthermore, political feasibility often requires non-restrictive emission caps. Grandfathering under lax cap is unjust, biased and brings polluters unintended windfall profits. Still, in any post-Kyoto international CO2 regime, lax caps may be critical in coaxing binding emission targets out of more countries, especially those in the less-developed world. This paper argues that there is a certain quantity of emission rights between the initial and the optimal emissions, the grandfathering of which brings polluters zero windfall profits or zero windfall losses. Our theoretical concept of zero-windfall grandfathering can be used to demonstrate the windfall profits that have emerged at company level during the first EU trading period. It might thus encourage governments to embrace auctioning, and to combine it with grandfathering as a legitimate tool in the initial allocation of emission rights in later trading regimes.
Resumo:
A lean menedzsment egészségügyi szolgáltatásokra való alkalmazásával elérhető eredmények egyre inkább nyilvánvalóvá válnak. Ennek köszönhetően a szektorban dinamikus növekedés tapasztalható ezen a téren. A kutatások azonban arra hívják fel a figyelmet, hogy a lean menedzsment alkalmazásával elért eredmények csak akkor lesznek fenntarthatóak, ha az eszközök alkalmazását a kultúra átalakulása is követi. A kultúra változásának követéséhez annak folyamatos értékelésére van szükség. A szervezeti kultúra lean-specifikus méréséhez azonban – a szerzők tudomása szerint – még nincs kidolgozott eszköz. Ezért cikkükben a kapcsolódó szakirodalom áttekintése után kidolgoztak egy lean kultúra kérdőívet, majd bemutatják a kérdőív tesztelését és annak eredményeit. Összegzésként elmondható, hogy az itt bemutatott kérdőív az első tesztelés alapján további fejlesztésre szorul. / === / The results that can be obtained by applying lean management in healthcare services become more and more clear. This generates a dynamic increase of lean applications in healthcare. However, researches are warning that the res ults obtained by lean applications can only be sustained, if next to the use of the lean tools cultural change will also take place. In order to track changes in culture its constant evaluation is necessary. According to the authors’ knowledge today does not exist any lean-specific culture evaluation tool. In this paper they elaborate a lean culture questionnaire based on the review of relevant literature. Than they describe its test and the results of the test. The authors conclude that the questionnaire as introduced here needs further improvement.
Resumo:
A márkatulajdonosok számára elsődleges fontosságú, hogy feltérképezzék saját márkaközösségüket, ezáltal is elősegítve a közösségi fókuszú kommunikációs tevékenységüket. Különösen igaz ez a jellemzően kis- és középvállalati formában működő vendéglátóhelyek számára, ahol a közösségi média sokszor az egyetlen rendelkezésre álló marketingkommunikációs eszköz. Empirikus kutatásunkban fogyasztói narratívákat (n=151) elemzünk a tartalomelemzés módszertanával. A válaszadókat arra kértük, hogy írjanak kedvenc vendéglátóhelyükkel való kapcsolatukról az online térben. Elemzésünkben arra keressük a választ, hogy a márkaközösségek tagjai milyen belső indíttatásból kerültek kapcsolatba kedvenc vendéglátóhelyeikkel a közösségi platformokon. Az elsősorban fogyasztási élményekhez kötött kapcsolat online közösségi térbe való kiterjesztésére olyan belső motivációkat tártunk fel, mint a pragmatikusabb információközpontú indíttatások (pl. kizárólagos információk, naprakészség, vállalati ajánlatok, közösségimédia-specifikus tartalmakhoz való hozzáférés igénye), az érzelmi kötődés kifejezése (pl. nosztalgia, ismerősöknek való ajánlás, személyes érintettség), a társas befolyás (oldalak kedvelése mint kommunikációs tartalom, konformitás, önkifejezés), valamint a vállalati alapképességeken túlmutató egyéb tematikus kapcsolódások. ____ It is of primary importance for brand owners to map their own brand community, in order to stimulate their social-focused communication activity. This is especially true for typically small and medium-sized catering enterprises, where in most cases, social media is the only available marketing communications tool. In our empirical research, we analyze consumer narratives (n=151) with the methodology of content analysis. We asked the respondents to write about their relationship with their most preferred catering establishments in the online social sphere. In our research, we search for the inner intention by which members of brand communities got connected with their most preferred catering establishments on social platforms. We revealed such inner motivations for users extending a primarily experience (an consumption) based relationship to the online social sphere like rather pragmatic, information-focused intentions (e.g. exclusive information, timeliness, company offers, access claim for social media -specific contents), the expression of emotional binding (e.g. nostalgia, reference for acquaintances, personal involvement), social influence (the like as communication content, conformity, self-expression), and other thematic linkages beyond core company competences.
Resumo:
The pine rocklands of South Florida, characterized by a rich herbaceous flora with many narrowly endemic taxa beneath an overstory of south Florida slash pine (Pinus elliottii var. densa), are found in three areas: the Miami Rock Ridge of southeastern peninsular Florida, the Lower Florida Keys, and slightly elevated portions of the southern Big Cypress National Preserve. Fire is an important element in these ecosystems, since in its absence the pine canopy is likely to be replaced by dense hardwoods, resulting in loss of the characteristic pineland herb flora. Prescribed fire has been used in Florida Keys pine forests since the creation of the National Key Deer Refuge (NKDR), with the primary aim of reducing fuels. Because fire can also be an effective tool in shaping ecological communities, we conducted a 4-year research study which explored a range of fire management options in NKDR. The intent of the study was to provide the Fish and Wildlife Service and other land managers with information regarding when and where to burn in order to perpetuate these unique forests.
Resumo:
Online learning systems (OLS) have become center stage for corporations and educational institutions as a competitive tool in the knowledge economy. The satisfaction construct has received extensive coverage in information systems literature as an indicator of effectiveness but has been criticized for lack of validity; yet, the value construct has been largely ignored, although it has a long history in psychology, sociology, and behavioral science. The purpose of this dissertation is to investigate the value and satisfaction constructs in the context of OLS, and their perceived by learners relationship for implied effectiveness of OLS. ^ First, a qualitative phase is employed to gather OLS values from learners' focus groups, followed by a pilot phase to refine a proposed instrument, and a main phase to validate the survey. Responses were received from 75 students in four focus groups, 141 in the pilot, and 207 the main survey. Extensive data cleaning and exploratory factor analysis were done to identify factors of learners' perceived value and satisfaction of OLS. Then, Value-Satisfaction grids and the Learners' Value Index of Satisfaction (LeVIS) were developed as benchmarking tools of OLS. Moreover, Multicriteria Decision Analysis (MCDA) techniques were employed to impute value from satisfaction scores in order to reduce survey response time. ^ The results provided four satisfaction and four value factors with high reliability (Cronbach's α). Moreover, value and satisfaction were found to have low linear and nonlinear correlations, indicating that they are two distinct uncorrelated constructs. This is consistent with the literature. Value-Satisfaction grids and the LeVIS index indicated relatively high effectiveness for technology and support characteristics, relatively low effectiveness for professor's characteristics, while course and learner characteristics indicated average effectiveness. ^ The main contributions of this study include identifying, defining, and articulating the relationship between value and satisfaction constructs as assessment of users' implied IS effectiveness, as well as assessing the accuracy of MCDA procedures to predict value scores, thus reducing by half the survey questionnaire size. ^
Resumo:
Recent technological developments have made it possible to design various microdevices where fluid flow and heat transfer are involved. For the proper design of such systems, the governing physics needs to be investigated. Due to the difficulty to study complex geometries in micro scales using experimental techniques, computational tools are developed to analyze and simulate flow and heat transfer in microgeometries. However, conventional numerical methods using the Navier-Stokes equations fail to predict some aspects of microflows such as nonlinear pressure distribution, increase mass flow rate, slip flow and temperature jump at the solid boundaries. This necessitates the development of new computational methods which depend on the kinetic theory that are both accurate and computationally efficient. In this study, lattice Boltzmann method (LBM) was used to investigate the flow and heat transfer in micro sized geometries. The LBM depends on the Boltzmann equation which is valid in the whole rarefaction regime that can be observed in micro flows. Results were obtained for isothermal channel flows at Knudsen numbers higher than 0.01 at different pressure ratios. LBM solutions for micro-Couette and micro-Poiseuille flow were found to be in good agreement with the analytical solutions valid in the slip flow regime (0.01 < Kn < 0.1) and direct simulation Monte Carlo solutions that are valid in the transition regime (0.1 < Kn < 10) for pressure distribution and velocity field. The isothermal LBM was further extended to simulate flows including heat transfer. The method was first validated for continuum channel flows with and without constrictions by comparing the thermal LBM results against accurate solutions obtained from analytical equations and finite element method. Finally, the capability of thermal LBM was improved by adding the effect of rarefaction and the method was used to analyze the behavior of gas flow in microchannels. The major finding of this research is that, the newly developed particle-based method described here can be used as an alternative numerical tool in order to study non-continuum effects observed in micro-electro-mechanical-systems (MEMS).
Resumo:
In fire-dependent forests, managers are interested in predicting the consequences of prescribed burning on postfire tree mortality. We examined the effects of prescribed fire on tree mortality in Florida Keys pine forests, using a factorial design with understory type, season, and year of burn as factors. We also used logistic regression to model the effects of burn season, fire severity, and tree dimensions on individual tree mortality. Despite limited statistical power due to problems in carrying out the full suite of planned experimental burns, associations with tree and fire variables were observed. Post-fire pine tree mortality was negatively correlated with tree size and positively correlated with char height and percent crown scorch. Unlike post-fire mortality, tree mortality associated with storm surge from Hurricane Wilma was greater in the large size classes. Due to their influence on population structure and fuel dynamics, the size-selective mortality patterns following fire and storm surge have practical importance for using fire as a management tool in Florida Keys pinelands in the future, particularly when the threats to their continued existence from tropical storms and sea level rise are expected to increase.
Resumo:
Purpose – The purpose of this paper is to provide an analysis of sistematización’s use as a research tool in the operationalization of a “neighborhood approach” to the implementation of disaster risk reduction (DRR) in informal urban settlements. Design/methodology/approach – The first section highlights sistematización’s historical origins in Latin America in the fields of popular adult education, social work, and rural development. The second explains why sistematización was made a required component of project implementation. The third section addresses the approach to sistematización used. The final discusses how this experience both contributes to sistematización’s theoretical development and practical application as a methodology. Findings – The introduction of “sistematización” as a research tool facilitated real-time assessment of project implementation, providing timely information that positively influenced decision-making processes. This on-going feedback, collective learning, and open-exchange of know-how between NGOs and partner institutions allowed for the evaluation of existing practices and development of new ways of collaborating to address disaster risk in complex and dynamic urban environments. Practical implications – Sistematización transcends the narrow focus of traditional monitoring and evaluation on final results, emphasizing a comprehensive understanding of processes and contexts. Originality/value – Its use in the implementation of DRR initiatives in informal urban environments is particularly novel, highlighting the capacity of the methodology to be tailored to a variety of needs, in this case, bridging the gap between NGOs, local governments, and vulnerable communities, as well as between urban, development, and disaster risk management planning.
Resumo:
BACKGROUND: The Pro Children Eating Habits Questionnaire has been evaluated as a valid and reliable tool in Europe to measure determinants of fruit and vegetable intake for children; however, it has not been validation for United States populations. The purpose of this study was to (1) assess the reliability and discrimination validity of fruit and vegetable correlates for the Pro Children Eating Habits Questionnaire; (2) investigate the predictive validity of determinants of fruit and vegetable consumption for multi-ethnic elementary school children; and, (3) to assess the association of social determinants with fruit and vegetable consumption. METHODS: One hundred and thirty elementary school students from the 3rd and 5th grades completed this cross-sectional study. RESULTS: Fruit and vegetable determinants, had satisfactory internal consistencies. No differences were found between the test and the retest for the individual questions with the exception of the question for mean perceived vegetable intake. The discriminatory validity indicated the questionnaire could show differences across grade and gender levels for barriers of fruit and vegetables but not for other factors. Grade together with gender explained barriers to eating fruit and vegetables. Greater availability of fruit in the home and school was associated with higher frequency of consumption. CONCLUSIONS: The results of this study indicate the Pro-Children Eating Habits Questionnaire may be a reliable and valid tool for assessing fruit and vegetable consumption of children in the United States.
Resumo:
This thesis describes the development of an adaptive control algorithm for Computerized Numerical Control (CNC) machines implemented in a multi-axis motion control board based on the TMS320C31 DSP chip. The adaptive process involves two stages: Plant Modeling and Inverse Control Application. The first stage builds a non-recursive model of the CNC system (plant) using the Least-Mean-Square (LMS) algorithm. The second stage consists of the definition of a recursive structure (the controller) that implements an inverse model of the plant by using the coefficients of the model in an algorithm called Forward-Time Calculation (FTC). In this way, when the inverse controller is implemented in series with the plant, it will pre-compensate for the modification that the original plant introduces in the input signal. The performance of this solution was verified at three different levels: Software simulation, implementation in a set of isolated motor-encoder pairs and implementation in a real CNC machine. The use of the adaptive inverse controller effectively improved the step response of the system in all three levels. In the simulation, an ideal response was obtained. In the motor-encoder test, the rise time was reduced by as much as 80%, without overshoot, in some cases. Even with the larger mass of the actual CNC machine, decrease of the rise time and elimination of the overshoot were obtained in most cases. These results lead to the conclusion that the adaptive inverse controller is a viable approach to position control in CNC machinery.
Resumo:
Recent technological developments have made it possible to design various microdevices where fluid flow and heat transfer are involved. For the proper design of such systems, the governing physics needs to be investigated. Due to the difficulty to study complex geometries in micro scales using experimental techniques, computational tools are developed to analyze and simulate flow and heat transfer in microgeometries. However, conventional numerical methods using the Navier-Stokes equations fail to predict some aspects of microflows such as nonlinear pressure distribution, increase mass flow rate, slip flow and temperature jump at the solid boundaries. This necessitates the development of new computational methods which depend on the kinetic theory that are both accurate and computationally efficient. In this study, lattice Boltzmann method (LBM) was used to investigate the flow and heat transfer in micro sized geometries. The LBM depends on the Boltzmann equation which is valid in the whole rarefaction regime that can be observed in micro flows. Results were obtained for isothermal channel flows at Knudsen numbers higher than 0.01 at different pressure ratios. LBM solutions for micro-Couette and micro-Poiseuille flow were found to be in good agreement with the analytical solutions valid in the slip flow regime (0.01 < Kn < 0.1) and direct simulation Monte Carlo solutions that are valid in the transition regime (0.1 < Kn < 10) for pressure distribution and velocity field. The isothermal LBM was further extended to simulate flows including heat transfer. The method was first validated for continuum channel flows with and without constrictions by comparing the thermal LBM results against accurate solutions obtained from analytical equations and finite element method. Finally, the capability of thermal LBM was improved by adding the effect of rarefaction and the method was used to analyze the behavior of gas flow in microchannels. The major finding of this research is that, the newly developed particle-based method described here can be used as an alternative numerical tool in order to study non-continuum effects observed in micro-electro-mechanical-systems (MEMS).
Resumo:
Primary processing of natural gas platforms as Mexilhão Field (PMXL-1 ) in the Santos Basin, where monoethylene glycol (MEG) has been used to inhibit the formation of hydrates, present operational problems caused by salt scale in the recovery unit of MEG. Bibliographic search and data analysis of salt solubility in mixed solvents, namely water and MEG, indicate that experimental reports are available to a relatively restricted number of ionic species present in the produced water, such as NaCl and KCl. The aim of this study was to develop a method for calculating of salt solubilities in mixed solvent mixtures, in explantion, NaCl or KCl in aqueous mixtures of MEG. The method of calculating extend the Pitzer model, with the approach Lorimer, for aqueous systems containing a salt and another solvent (MEG). Python language in the Integrated Development Environment (IDE) Eclipse was used in the creation of the computational applications. The results indicate the feasibility of the proposed calculation method for a systematic series of salt (NaCl or KCl) solubility data in aqueous mixtures of MEG at various temperatures. Moreover, the application of the developed tool in Python has proven to be suitable for parameter estimation and simulation purposes
Resumo:
This thesis explores the ritual of prayer among Muslim immigrants in the city of St. John's, NL. Immigration across national, cultural, religious, and ethnic borders is a moment in an individual's life marked by significant change. My premise is that in such contexts the relatively conservative nature of religious ritual can supply much-needed continuity, comfort, and consolation for individuals living through the immigrant experience. As well, ritual forms are often put under stress when transferred to a considerably different place and cultural context, where “facts on the ground” may be obstacles to traditional and familiar ritual forms. Changes to the understanding or practice of ritual are common in new cultural and geographic situations, and ritual itself often becomes not merely a means of social identification and cohesion, but a practical tool in processing change - in the context of immigration, in learning to live in a new community. St. John's is a lively and historic city and while Muslim immigrants may be a small group within it they nevertheless contribute to the city's energy and atmosphere. This thesis endeavours to better understand the life stories of ten of these newcomers to St. John's, focusing on their religious backgrounds and lives. In particular, this thesis seeks to better understand the place of prayer in the immigrant experience.
Resumo:
Several previous studies have shown that submarine mass-movements can profoundly impact the shape of pore water profiles. Therefore, pore water geochemistry and diffusion models were proposed as tools for identifying and dating recent (max. several thousands of years old) mass-transport deposits (MTDs). In particular, sulfate profiles evidentially indicate transient pore water conditions generated by submarine landslides. After mass-movements that result in the deposition of sediment packages with distinct pore water signatures, the sulfate profiles can be kink-shaped and evolve into the concave and linear shape with time due to molecular diffusion. Here we present data from the RV METEOR cruise M78/3 along the continental margin off Uruguay and Argentina. Sulfate profiles of 15 gravity cores are compared with the respective acoustic facies recorded by a sediment echosounder system. Our results show that in this very dynamic depositional setting, non-steady state profiles occur often, but are not exclusively associated with mass-movements. Three sites that show acoustic indications for recent MTDs are presented in detail. Where recent MTDs are identified, a geochemical transport/reaction model is used to estimate the time that has elapsed since the perturbation of the pore water system and, thus, the timing of the MTD emplacement. We conclude that geochemical analyses are a powerful complementary tool in the identification of recent MTDs and provide a simple and accurate way of dating such deposits.