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Layer Of Protection Analysis: Pilotstudie, metodutveckling och tillämpning på ett konventionellt hydrauliskt bromssystem / Layer Of Protection Analysis: Pilot study, method development and application on a hydraulic braking systemRahimi ata, Kooscha-Kevin January 2019 (has links)
Within the safety analysis industry there are a variety of tools used to ensure reliability and security of systems, ranging from mostly qualitative approaches to mostly quantitative. One safety analysis method that lies in between these two is called Layers Of Protection Analysis (LOPA). LOPA is known as a “semi-quantitative” approach that uses a mix of quantitative and qualitative approaches to draw conclusions. In this masters thesis the LOPA approach is demonstrated, in addition to being developed into two alternate LOPA approaches, known as MarkovLOPA and RBDLOPA. These two developed approaches use the concept of Markov chains and Reliability block diagram (RBD) respectively, to extend the applicability of the traditional LOPA methodology. Furthermore, a conventional hydraulic braking system (CHB), which includes ABS/TCS- and ESP functionality was analysed by these three methodologies. The results of the analysis show that in the analysis by LOPA and RBDLOPA 4- and 3 out of 10 scenarios need slight improvements and only 1 scenario for MarkovLOPA. Additionally, the validity of the alternative approaches are analysed by a sensitivity analysis, showing irregularities in the results, leading to the conclusion that further research and development is required prior to industrial applications of the approaches.
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Caracterização de crime ambiental de poluição por meio de abordagem multiparamétrica e incorporando incerteza de amostragem / A multiparameter approach to characterize environmental pollution crime incorporating the uncertainty of samplingBARBIERI, CRISTINA B. 22 June 2016 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-06-22T13:58:45Z
No. of bitstreams: 0 / Made available in DSpace on 2016-06-22T13:58:45Z (GMT). No. of bitstreams: 0 / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Caracterização de crime ambiental de poluição por meio de abordagem multiparamétrica e incorporando incerteza de amostragem / A multiparameter approach to characterize environmental pollution crime incorporating the uncertainty of samplingBARBIERI, CRISTINA B. 22 June 2016 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-06-22T13:58:45Z
No. of bitstreams: 0 / Made available in DSpace on 2016-06-22T13:58:45Z (GMT). No. of bitstreams: 0 / As agressões ao meio ambiente, num contexto de esgotamento de recursos naturais, vêm recebendo crescente importância aos olhos da sociedade e, nesse cenário, o meio ambiente passou a ser protegido pelo Direito Penal. Assim, muitas destas agressões, como a poluição, passaram a ser qualificadas como crimes ambientais tornando se necessária a produção de prova técnica para o seu devido julgamento. Este trabalho apresenta uma nova estratégia para caracterização de crimes ambientais de poluição e correlatos baseado em abordagem multiparamétrica. Para isso foram utilizadas análises de diferentes parâmetros como metais, razões de isótopos estáveis e compostos orgânicos (hidrocarbonetos aromáticos policíclicos), e análise estatística multivariada, com o intuito de obter uma assinatura química robusta dos poluentes da fonte suspeita e assim estabelecer correspondência com os mesmos parâmetros determinados no compartimento ambiental receptor. Ainda, foram incorporados alguns conceitos de metrologia, como o cálculo de incerteza de amostragem, conforme preceituam as novas tendências de desenvolvimento conceitual e metodológico das ciências forenses. Os sedimentos de um curso dágua altamente impactado por descargas diversas foram o objeto das investigações como sendo o compartimento receptor e o percolado de um aterro de resíduos industriais perigosos envolvido em um crime ambiental foi analisado como possível fonte. A abordagem multiparamétrica utilizada neste trabalho proporcionou uma melhor discriminação dos pontos de coleta com base na sua localização com relação às fontes de poluição por meio da Análise de Componentes Principais e as análises de metais realizadas nos sedimentos permitiram caracterizar um crime de poluição ambiental. As estimativas de incerteza de amostragem evidenciaram variações nos resultados principalmente decorrentes da heterogeneidade da distribuição dos contaminantes no meio o que implica que as incertezas devem, preferencialmente, ser estimadas e reportadas nas medições no âmbito forense para um efetivo apoio às tomadas de decisões nelas baseadas. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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A comunicação dos riscos na preparação para emergências nucleares: um estudo de caso em Angra dos Reis, Rio de Janeiro / Risk communication in preparation for nuclear emergencies: a case study in Angra dos Reis, Rio de JaneiroCUNHA, RAQUEL D.S. da 21 November 2017 (has links)
Submitted by Pedro Silva Filho (pfsilva@ipen.br) on 2017-11-21T11:45:58Z
No. of bitstreams: 0 / Made available in DSpace on 2017-11-21T11:45:58Z (GMT). No. of bitstreams: 0 / O gerenciamento de riscos em uma instalação nuclear é necessário para a segurança de trabalhadores e de populações vizinhas. Parte desse processo é a comunicação dos riscos que propicia o diálogo entre gestores da empresa e moradores das áreas de risco. A população que conhece os riscos a que está exposta, como esses riscos são gerenciados e o que deve ser feito em uma situação de emergência tende a se sentir mais segura e a confiar nas instituições responsáveis pelo plano de emergência. Sem diálogo entre empresa e público, o conhecimento dos procedimentos a serem seguidos em caso de acidente não chega à população, ou quando chega, não há confiança dessas pessoas na sua eficácia. Em Angra dos Reis, no litoral sul do Estado do Rio de Janeiro, está a Central Nuclear Almirante Álvaro Alberto. No entorno dessa Central Nuclear existe uma população que, de acordo com o Plano de Emergência Externo (PEE/RJ), deverá ser evacuada ou ficar abrigada, caso ocorra um acidente na instalação. Um trabalho de comunicação de riscos entre esses moradores é necessário para que eles conheçam o plano de emergência e os procedimentos corretos para uma situação de emergência, além de buscar esclarecer dúvidas e mitos. Esse trabalho apresenta uma análise da comunicação dos riscos feita para a população local, a percepção que ela tem dos riscos e o grau de conhecimento do plano de emergência externo por parte dessas pessoas. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
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Development and validation of a multi-scale and multi-physics methodology for the safety analysis of fast transients in Light Water ReactorsHidalga García-Bermejo, Patricio 25 January 2021 (has links)
[ES] La tecnología nuclear para el uso civil genera más preocupación por la seguridad que muchas otras tecnologías que se usan a diario. La Autoridad Nuclear define las bases de cómo debe realizarse la operación segura de una Central Nuclear. De acuerdo a las directrices establecidas por la Autoridad Nuclear, una Central Nuclear debe analizar una envolvente de escenarios hipotéticos y comprobar de manera determinista que los criterios de aceptación para dicho evento se cumplen. El Análisis Determinista de Seguridad utiliza herramientas de simulación que aplican la física conocida sobre el comportamiento de la Central Nuclear para evaluar la evolución de una variable de seguridad y asegurar que los límites no se sobrepasan.
El desarrollo de la tecnología informática, de los métodos matemáticos y de la física que envuelve el comportamiento de una Central Nuclear han proporcionado herra-mientas de simulación potentes que son capaces de predecir el comportamiento de las variables de seguridad con una importante precisión. Esto permite analizar escenarios de manera más realista evitando asumir condiciones conservadoras que hasta la fecha compensaban la falta de conocimiento modelado en las herramientas de simulación. Las herramientas conocidas como De Mejor Estimación son capaces de analizar even-tos transitorios en diferentes escalas. Además, emplean modelos analíticos de las dife-rentes físicas más detallados, así como correlaciones experimentales más realistas y actuales. Un paso adelante en el Análisis Determinista de Seguridad pretende combinar las diferentes herramientas de Mejor Estimación que se emplean para analizar las dis-tintas físicas de una Central Nuclear, considerando incluso la interacción entre ellas y el análisis progresivo a diferentes escalas, llegando a analizar fenómenos más locales si es necesario.
Para este fin, esta tesis presenta una metodología de análisis multi-físico y multi-escala que emplea diferentes códigos de simulación analizando el escenario propuesto a dife-rentes escalas, es decir, desde un nivel de planta que incluye los distintos componentes, hasta el volumen de control que supone el refrigerante pasando entre las varillas de combustible. Esta metodología permite un flujo de información que va desde el análi-sis a mayor escala hasta el de menor escala. El desarrollo de esta metodología ha sido validado con datos de planta para poder evaluar el alcance de esta metodología y pro-porcionar nuevas líneas de trabajo futuro. Además, se han añadido los resultados de los distintos procesos de validación y verificación que han surgido a lo largo de este trabajo. / [CA] La tecnologia nuclear per a l'ús civil genera més preocupació per la seguretat que moltes altres tecnologies d'ús quotidià. L'Autoritat Nuclear defineix les bases de com ha de realitzar-se l'operació segura d'una Central Nuclear. D'acord amb les directrius establertes per l'Autoritat Nuclear, una Central Nuclear ha d'analitzar una envoltant d'escenaris hipotètics I comprovar de manera determinista que els criteris d'acceptació per a l'esdeveniment seleccionat es compleixen. L'Anàlisi Determinista de Seguretat utilitza eines de simulació que apliquen la física coneguda sobre el comportament de la Central Nuclear per avaluar l'evolució d'una variable de seguretat i assegurar que els límits no es traspassen.
El desenvolupament de la tecnologia informàtica, els mètodes matemàtics i de la física que envolta el comportament d'una Central Nuclear han proporcionat eines de simulació potents amb capacitat de predir el comportament de les variables de seguretat amb una precisió significativa. Això permet analitzar escenaris de manera realista evitant assumir condicions conservadores que fins al moment compensaven la mancança de coneixement. Les eines de simulació conegudes com De Millor Estimació son capaces d'analitzar esdeveniment transitoris a diferent escales. A més, utilitzen models analítics per a les diferents físiques amb més detall així com correlacions experimentals més actualitzades i realistes. Un pas més endavant en l'Anàlisi Determinista de Seguretat pretén combinar les diferents eines de Millor Estimació que se utilitzen per analitzar les distintes físiques d'una Central Nuclear, considerant inclús la interacció entre ells i l'anàlisi progressiu a diferents escales, amb la finalitat de poder analitzar fenòmens locals.
Per a aquest fi, esta tesi presenta una metodologia d'anàlisi multi-física i multi-escala que utilitza diferents codis de simulació analitzant l'escenari proposat a diferents escales, és a dir, des d'un nivell de planta que inclou els distints components, fins al volum de control que suposa el refrigerant passant entre les varetes de combustible. Esta metodologia permet un flux de informació que va des de l'anàlisi d'una escala major a una menor. El desenvolupament d'aquesta metodologia ha sigut validada i verificada amb dades de planta i els resultats han sigut analitzats a fi d'avaluar la capacitat de la metodologia i les possibles línies de treball futur. A més s'han afegit els principals resultats de verificació i validació que han sorgit en les distintes etapes d'aquest treball. / [EN] The nuclear technology for civil use has generated more concerns for the safety than several other technologies applied to the daily life. The Nuclear Regulators define the basis of how the Safety Operation of Nuclear Power Plants is to be done. According to these guidelines, a Nuclear Power Plant must analyze an envelope of hypothetical events and deterministically define if the acceptance criteria for these events is met. The Deterministic Safety Analysis uses simulation tools that apply the physics known in the behavior of the Nuclear Power Plant to evaluate the evolution of a safety varia-ble and assure that the safety limits will not be exceeded.
The development of the computer science, the numerical methods and the physics involved in the behavior of a Nuclear Power Plant have yield powerful simulation tools that are capable to predict the evolution of safety variables which significant accuracy. This allows to consider more realistic simulation scenarios instead of con-servative approaches in order to compensate the lack of knowledge in the applied prediction methods. The so called Best Estimate simulation tools are capable to analyze the transient events in different scales. Furthermore, they account more detailed analytical models and experimental correlations. A step forward in the Deterministic Safety Analysis intends to combine the Best Estimate simulation tools of the different physics considering the interaction among them and analyzing the different scales, considering more local approaches if necessary.
For this purpose, this thesis work presents a multi-scale and multi-physics methodology that uses different physics codes and has the aim of modeling postulated scenarios in different scales, i.e. from system models representing the components of the plants to the subchannel models that analyze the behavior of the coolant between the fuel rods. This methodology allows a flow of information where the output of one scale is used as input in a more detailed scale to predict a more local analysis of parameters, such as the Critical Power Ratio, which are of great importance for the estimation of safety margins. The development of this methodology has been validated against plant data with the aim of evaluating the scope of this methodology and in order to provide future lines of development. In addition, different results of the validation and verifi-cation yielded in the development of the parts of this methodology are presented. / Hidalga García-Bermejo, P. (2020). Development and validation of a multi-scale and multi-physics methodology for the safety analysis of fast transients in Light Water Reactors [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/160135
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Desenvolvimento e validação de um referencial metodológico para avaliação da cultura de segurança de organizações nucleares / Development and validation of a methodological framework for assessing the safety culture of nuclear organizationsMOMESSO, ROBERTA G.R.A.P. 22 November 2017 (has links)
Submitted by Pedro Silva Filho (pfsilva@ipen.br) on 2017-11-22T16:34:17Z
No. of bitstreams: 0 / Made available in DSpace on 2017-11-22T16:34:17Z (GMT). No. of bitstreams: 0 / A cultura de segurança na área nuclear é definida como o conjunto de características e atitudes da organização e dos indivíduos que fazem que, com uma prioridade insuperável, as questões relacionadas à proteção e segurança nuclear recebam a atenção assegurada pelo seu significado. Até o momento, não existem instrumentos validados que permitam avaliar a cultura de segurança na área nuclear. Em vista disso, os resultados da definição de estratégias para o seu fortalecimento e o acompanhamento do desempenho das ações de melhorias tornam-se difíceis de serem avaliados. Este trabalho teve como objetivo principal desenvolver e validar um instrumento para a avaliação da cultura de segurança de organizações nucleares, utilizando o Instituto de Pesquisas Energéticas e Nucleares como unidade de pesquisa e coleta de dados. Os indicadores e variáveis latentes do instrumento foram definidos utilizando como referência modelos de avaliação de cultura de segurança da área da saúde e área nuclear. O instrumento de coleta de dados proposto inicialmente foi submetido à avaliação por especialistas da área nuclear e, posteriormente, ao pré-teste com indivíduos que pertenciam à população pesquisada. A validação do modelo foi feita por meio da modelagem por equações estruturais utilizando o método de mínimos quadrados parciais (Partial Least Square - Structural Equation Modeling PLS-SEM), no software SmartPLS. A versão final do instrumento foi composta por quarenta indicadores distribuídos em nove variáveis latentes. O modelo de mensuração apresentou validade convergente, validade discriminante e confiabilidade e, o modelo estrutural apresentou significância estatística, demonstrando que o instrumento cumpriu adequadamente todas as etapas de validação. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
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Feed-and-bleed transient analysis of OSU APEX facility using the modern Code Scaling, Applicability, and Uncertainty methodHallee, Brian Todd 05 March 2013 (has links)
The nuclear industry has long relied upon bounding parametric analyses in predicting the safety margins of reactor designs undergoing design-basis accidents. These methods have been known to return highly-conservative results, limiting the operating conditions of the reactor. The Best-Estimate Plus Uncertainty (BEPU) method using a modernized version of the Code-Scaling, Applicability, and Uncertainty (CSAU) methodology has been applied to more accurately predict the safety margins of the Oregon State University Advanced Plant Experiment (APEX) facility experiencing a Loss-of-Feedwater Accident (LOFA). The statistical advantages of the Bayesian paradigm of probability was utilized to incorporate prior knowledge when determining the analysis required to justify the safety margins. RELAP5 Mod 3.3 was used to accurately predict the thermal-hydraulics of a primary Feed-and-Bleed response to the accident using assumptions to accompany the lumped-parameter calculation approach. A novel coupling of thermal-hydraulic and statistical software was accomplished using the Symbolic Nuclear Analysis Package (SNAP). Uncertainty in Peak Cladding Temperature (PCT) was calculated at the 95/95 probability/confidence levels under a series of four separate sensitivity studies. / Graduation date: 2013
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Improving the turnaround maintenance of the Escravos gas plant / Ishekwene, I.V.Ishekwene, Isaac Victor January 2011 (has links)
According to Oliver (2002) the success of turnaround maintenances is measured in terms of the
cost of completion, time, safety performance and the performance of the plant afterwards.
The Escravos gas plant (EGP) is a gas processing plant that converts associated gas from
Chevron owned crude oil wells to liquefied petroleum gas, natural gas and gas condensate
(Chevron intranet. Website assessed on September 14, 2007).
According to the EGP plant operations coordinator (See interview Appendix A), the plant
undergoes a turnaround maintenance exercise once every two years. The major tasks done during
these turnaround maintenances are
1. Change–out of three molecular sieve beds.
2. Servicing of three compressor turbines.
3. Servicing of expander turbo–machinery.
4. Clean–out of fired gas heater tubes and burners.
5. Tie–ins for major upgrades.
The EGP management does not involve the contractor personnel that carry out the tasks in the
management of the turnaround maintenance. The contractor’s personnel simply follow the work
plans and instructions developed by the EGP management.
The EGP turnaround management team consists of the coordinator who is the head of the
turnaround maintenance team, shift supervisors, maintenance supervisors (rotating equipment
maintenance supervisor, instrumentation and electrical maintenance supervisor, and static
equipment maintenance supervisors), safety supervisors, maintenance planners, process
engineers and construction supervisors.
All these listed personnel in the preceding paragraph and the supervisors of the contractor teams
participate in the pre–turnaround meetings which happen once a month for the first 10 months of
the 12 months leading to the turnaround. The meeting frequency increases to once every two
weeks during the last two months leading to the turnaround maintenance. The meeting is held daily during the turnaround maintenance and once every two weeks for the first month after the turnaround maintenance.
During the preceding months to the turnaround maintenance, the work scope is defined, the job
sequence outlined and schedules are developed. Resources requirements are detailed and
procured. During the turnaround maintenance the focus of the turnaround meeting is to discuss
potential deviations, observe at–risk behaviors and likely challenges. Plans are then made to
address these deviations, challenges and at–risk behaviors. After the turnaround maintenance,
“lessons learnt” are captured and the turnaround maintenance is closed out.
According to the EGP coordinator (see interview in appendix A), the success of its turnaround
maintenance is measured by the time used to complete the turnaround maintenance, the total
recordable incident rate during the turnaround maintenance, the days away from work, the lost
time injury(LTI) and the cost incurred.
Poling et al noted that it is difficult to rate turnaround maintenance projects because no two
turnaround maintenances strategies are exactly the same. They iterated that the most common
tactics used is benchmarking and that benchmarking enables a company to measure and compare
its performance against peer companies in a constructive and confidential manner. They pointed
out that the quantitative differences computed between a plant and other similar plants using
detailed data taxonomy can provide invaluable information regarding improvement
opportunities. This is a way of effectively extending a “lessons learned” exercise across multiple
companies. According to then however a critical attribute of effective reliability and maintenance
benchmarking is the ability to compare disparate assets; but even small differences for similar
plants can alter the value of the comparison.
Existing literature indicate that the parameters the gas plant management use to rate the safety of
its turnaround maintenance (i.e. the total recordable incident rate, the days away from work and
the lost time injury)are reactive in nature. They are otherwise called lagging indicators. Lagging
indicators are safety performance metrics that are recorded after the accident or incidents has
occurred. For example lost time injury is any work related injury or illness which prevents that person from doing any work day after accident (E&P Consultancy Associates. Website assessed
on June 15, 2009). In contrast the other group of metrics called pro–active metrics or leading
indicators such as at–risk behaviors, near misses and preventive maintenance not completed are
parameters that measure safety performance before accident occurs.
Leading indicators gained popularity in the 1930’s after Heinrich postulate his iceberg theory
(Wright, 2004). Heinrich’s used the iceberg analogy to explain reactive (lagging) and proactive
(leading) indicators. Heinrich likened accident and at–risk behaviors to two parts of an Iceberg;
the part you see above water and the part hidden under the water. The size of the iceberg above
water is relatively small compared to that under water. The iceberg starts to grow under the water
and only after they reach a certain size does part of the ice begin to appear above water. Heinrich
believed that accidents are the result of root causes such as at–risk behaviors, inconsistencies,
wrong policies, lack of training and lack of information. When the number of accidents that
occur in an endeavor is measured you get relatively smaller numerical quantities when compared
to the number of at–risk behaviors.
Heinrich suggested that to eliminate accidents that occur infrequently, organizations must make
effort to eliminate the root causes which occur very frequently. This makes sense because
imagine a member of personnel coming to work intoxicated every day. Binging intoxicated at
work is an at–risk behavior. The employee is very likely to be involved in an accident at some
time as a result of his drinking habit. The number of times he is intoxicated if counted will be
huge when compared to the impact of the accident when it does occur.
The iceberg theory is supported by work from Bird (1980) and Ludwig (1980) who both
attempted to establish the correct ratio of accidents to root causes in different industries. Heinrich
suggested a ratio of three hundred incidents to twenty nine minor injuries to one major injury.
This researcher chose to use the number of at–risk behavior exhibited by the turnaround
maintenance teams to rate the safety performance of tasks despite criticism from individuals like
Robotham (2004) who said that from his experience minor incidents do not have the potential to
become major accidents and Wright et al (2004).
Leading indicators are convenient to analysis because of their relative large quantity. In a
turnaround environment, the numbers of accidents that occur are relatively few unlike the
number of near misses (Bird, 1980). It is easy to statistically analyze thirty at–risk behaviors than
four accidents. In addition Fleming et al (2001) noted that data from industry show much success
by companies in the reduction of accidents by efforts at reducing the number of at–risk behaviors,
increase the number of safety audits, and reduce the number of closed items from audits etc.
Phimister et al made similar claims when they said Near miss programs improve corporate
environmental, health and safety performance through the identification of near misses.
Existing literature also reveals many theories about management styles and their possible impact
on performance. The theories are grouped into trait theories, situational theories and behavioral
theories. The trait theories tries to explain management styles by traits of the managers like
initiative, wisdom, compassion and ambitious. Situational theories suggest that there is no best
management style and managers will need to determine which management style best suit the
situation. Behavioral theories explain management success by what successful managers do.
Behavioral theorists identify autocratic, benevolent, consultative and participatory management
styles. Vroom and Yetton (1973) identified variables that will determine the best management
style for any given situation. The variables are;
1. Nature of the problem. Is it simple, hard, complex or clear?
2. Requirements for accuracy. What is the consequence of mistakes?
3. Acceptance of an initiative. Do you want people to use their initiative or not?
4. Time–constraints. How much time do we have to finish the task?
5. Cost constraints. Do we have enough or excess to achieve the objective?
A decision model was developed by Vroom and Yago (1988)to help managers determine the best
management style for different situations based on the variables listed above (See figure six).
They also defined five management style could adopt, namely the;
1. Autocratic I style
2. Autocratic II style.
3. Consultative I style
4. Consultative II style
5. Group II style
The autocratic I management style is a management style where the leader solves the problem
alone using information that is readily available to him/her, is the normal management style of
the Escravos gas plant management in all turnarounds prior to 2009. However the Vroom and
Yago model recommends the Consultative II management style for the type of work done during
the Escravos gas plant turnaround maintenance.
According to Coye et al (1995), participatory management or consultative style II creates a sense
of ownership in organization. In this management style the leader shares problem with group
members individually, and asks for information and evaluation. Group members do not meet
collectively, and leader makes decision alone (Vroom and Yago, 1988). Coye et al believe that
this management styles instills a sense of pride and motivate employees to increase productivity.
In addition they stated that employees who participate in the decisions of the organization feel
like they are a part of a team with a common goal, and find their sense of self–esteem and
creative fulfillment heightened.
According to Filley et al (1961), Spector and Suttle did not find any significant difference in the
output of employees under autocratic and participatory management style.
This research studies if and how the Escravos gas plant turnaround maintenance can be improved
by changing the management style from autocratic I style to consultative II style. Two tasks in
the turnaround were studied; namely the change out of the molecular sieve catalyst beds and the
servicing of the turbine engines.
The turnaround contractor Techint Nigeria Limited divides the work group into teams
responsible for specific tasks. Six teams (team A, B, C, D, E and F) were studied. EGP
management will not allow the researcher to study more than these six teams for fear of the
research disrupting the work. The tasks completed by these teams are amongst those not on the projects critical path so delays caused by the research will not impact the entire turnaround
project provided the float on these activities were not exceeded. They also had the fewest number
of personnel, so cost impact of the research work could be easier to manager.
Teams A, B and C are different maintenance teams comprising of eight personnel each. They
were responsible for changing the EGP molecular sieve beds A, B and C respectively in the 2007
and 2009 turnaround. Their tasks are identical because the molecular sieve beds are identical.
Teams E, D and F are also maintenance teams comprising of six personnel each. They were
responsible for servicing the EGP turbine engines A, B and C during the 2007 and 2009
turnaround maintenance. Their tasks are also identical because the turbine engines are identical.
Consultative management style II is exercised by involving team A and team D in the
development of the procedures, processes and job safety analysis of all tasks that they were
assigned to complete during the 2009 turnaround maintenance. They were also permitted to
participate in the turnaround maintenance meetings and to make contributions in the meetings. In
the 2007 turnaround maintenance team A and team D only carried out their tasks. They did not
participate in the development of procedures and job safety analysis neither did they participate
in the turnaround maintenance meetings.
The other four teams; team B, team C, team E and team F are used as experimental controls for
the research. They did not participate in the development of the procedures, processes nor the job
safety analysis for the tasks in either of the turnaround maintenance. They were also not
permitted to attend the daily turnaround meetings. They only completed their tasks based on
instructions given to them during the 2007 and 2009 turnaround maintenance.
It was necessary to study the experimental control teams as the researcher was not sure whether
task repetition, increased knowledge or improved team cohesion would lead to a reduced time or
a reduced numbers of at–risk behavior.
ix
The research tested the hypothesis 1H0 and 1H1 and 2H0and 2H1 at the 0.025 and 0.05 level of
significance as follows;
Null hypothesis, 1H0: There is no significant difference in the time spent by team A and team
Din 2007 when they did not participate in the development of the procedures and processes with
the time in 2009 when they did(u1-u2=0).
Alternate hypothesis, 1H1: There is a significant difference in the time spent by the team A and
Din 2007 when they did not participate in the development of the procedures and processes with
the time in 2009 when they did (u1-u2!=0).
Null hypothesis, 2H0: There is no significant difference in the number of at–risk behaviors
observed to have been exhibited by the team A and team D in 2007 when they did not participate
in the development of the procedures and processes with the number in 2009 when they did (u1-u2=0).
Alternate hypothesis, 2H1: There is a significant difference in the number of at–risk behaviors
observed to have been exhibited by the team A and team D in 2007 when they did not participate
in the development of the procedures and processes with the number in 2009 when they did (u1-u2!=0).
The student t test was used to analyze these times and number of at–risk behavior. At the 0.025
and the 0.05 level of significance, the data show that there is no difference in the times all the
teams used to complete their task in 2007 and in 2009. The researcher concludes that a change in
the management style from autocratic I style to consultative II style did not lead to a reduction in
the time used by any team to complete their task.
However at the 0.025 and the 0.05 level of significance, there is a significant difference in the
number of at–risk behaviors of the research team A and team D. There is however no significant
difference in the number of at–risk behavior of the control team B, team C, team E and team F at
the same level of significance. The researcher concludes that a change in the management style from autocratic I style to consultative II style lead to a reduction in the number of at–risk
behavior of team A and team D.
In addition the reduction in the number of at–risk behavior of team A and team D could not have
been because of task repetition, increased knowledge or improved team cohesion since there is
no significant difference in the number of at–risk behavior exhibited by team B, team C, team E
and team F.
The research can be used by the Escravos gas plant management and the management of any
similar process plant to fashion out more cost effective, time effective and safer methods for
carrying out their turnaround maintenance. A change in management styles may just be a better
approach to improving productivity than giving financial incentives to contractors and personnel.
Changes in management style will have to be managed. The change must be gradual because
sudden change can be detrimental as people may just need to understand and adapt to the change.
The turnaround personnel must also understand the intent so as to prevent conflicts. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2012.
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Improving the turnaround maintenance of the Escravos gas plant / Ishekwene, I.V.Ishekwene, Isaac Victor January 2011 (has links)
According to Oliver (2002) the success of turnaround maintenances is measured in terms of the
cost of completion, time, safety performance and the performance of the plant afterwards.
The Escravos gas plant (EGP) is a gas processing plant that converts associated gas from
Chevron owned crude oil wells to liquefied petroleum gas, natural gas and gas condensate
(Chevron intranet. Website assessed on September 14, 2007).
According to the EGP plant operations coordinator (See interview Appendix A), the plant
undergoes a turnaround maintenance exercise once every two years. The major tasks done during
these turnaround maintenances are
1. Change–out of three molecular sieve beds.
2. Servicing of three compressor turbines.
3. Servicing of expander turbo–machinery.
4. Clean–out of fired gas heater tubes and burners.
5. Tie–ins for major upgrades.
The EGP management does not involve the contractor personnel that carry out the tasks in the
management of the turnaround maintenance. The contractor’s personnel simply follow the work
plans and instructions developed by the EGP management.
The EGP turnaround management team consists of the coordinator who is the head of the
turnaround maintenance team, shift supervisors, maintenance supervisors (rotating equipment
maintenance supervisor, instrumentation and electrical maintenance supervisor, and static
equipment maintenance supervisors), safety supervisors, maintenance planners, process
engineers and construction supervisors.
All these listed personnel in the preceding paragraph and the supervisors of the contractor teams
participate in the pre–turnaround meetings which happen once a month for the first 10 months of
the 12 months leading to the turnaround. The meeting frequency increases to once every two
weeks during the last two months leading to the turnaround maintenance. The meeting is held daily during the turnaround maintenance and once every two weeks for the first month after the turnaround maintenance.
During the preceding months to the turnaround maintenance, the work scope is defined, the job
sequence outlined and schedules are developed. Resources requirements are detailed and
procured. During the turnaround maintenance the focus of the turnaround meeting is to discuss
potential deviations, observe at–risk behaviors and likely challenges. Plans are then made to
address these deviations, challenges and at–risk behaviors. After the turnaround maintenance,
“lessons learnt” are captured and the turnaround maintenance is closed out.
According to the EGP coordinator (see interview in appendix A), the success of its turnaround
maintenance is measured by the time used to complete the turnaround maintenance, the total
recordable incident rate during the turnaround maintenance, the days away from work, the lost
time injury(LTI) and the cost incurred.
Poling et al noted that it is difficult to rate turnaround maintenance projects because no two
turnaround maintenances strategies are exactly the same. They iterated that the most common
tactics used is benchmarking and that benchmarking enables a company to measure and compare
its performance against peer companies in a constructive and confidential manner. They pointed
out that the quantitative differences computed between a plant and other similar plants using
detailed data taxonomy can provide invaluable information regarding improvement
opportunities. This is a way of effectively extending a “lessons learned” exercise across multiple
companies. According to then however a critical attribute of effective reliability and maintenance
benchmarking is the ability to compare disparate assets; but even small differences for similar
plants can alter the value of the comparison.
Existing literature indicate that the parameters the gas plant management use to rate the safety of
its turnaround maintenance (i.e. the total recordable incident rate, the days away from work and
the lost time injury)are reactive in nature. They are otherwise called lagging indicators. Lagging
indicators are safety performance metrics that are recorded after the accident or incidents has
occurred. For example lost time injury is any work related injury or illness which prevents that person from doing any work day after accident (E&P Consultancy Associates. Website assessed
on June 15, 2009). In contrast the other group of metrics called pro–active metrics or leading
indicators such as at–risk behaviors, near misses and preventive maintenance not completed are
parameters that measure safety performance before accident occurs.
Leading indicators gained popularity in the 1930’s after Heinrich postulate his iceberg theory
(Wright, 2004). Heinrich’s used the iceberg analogy to explain reactive (lagging) and proactive
(leading) indicators. Heinrich likened accident and at–risk behaviors to two parts of an Iceberg;
the part you see above water and the part hidden under the water. The size of the iceberg above
water is relatively small compared to that under water. The iceberg starts to grow under the water
and only after they reach a certain size does part of the ice begin to appear above water. Heinrich
believed that accidents are the result of root causes such as at–risk behaviors, inconsistencies,
wrong policies, lack of training and lack of information. When the number of accidents that
occur in an endeavor is measured you get relatively smaller numerical quantities when compared
to the number of at–risk behaviors.
Heinrich suggested that to eliminate accidents that occur infrequently, organizations must make
effort to eliminate the root causes which occur very frequently. This makes sense because
imagine a member of personnel coming to work intoxicated every day. Binging intoxicated at
work is an at–risk behavior. The employee is very likely to be involved in an accident at some
time as a result of his drinking habit. The number of times he is intoxicated if counted will be
huge when compared to the impact of the accident when it does occur.
The iceberg theory is supported by work from Bird (1980) and Ludwig (1980) who both
attempted to establish the correct ratio of accidents to root causes in different industries. Heinrich
suggested a ratio of three hundred incidents to twenty nine minor injuries to one major injury.
This researcher chose to use the number of at–risk behavior exhibited by the turnaround
maintenance teams to rate the safety performance of tasks despite criticism from individuals like
Robotham (2004) who said that from his experience minor incidents do not have the potential to
become major accidents and Wright et al (2004).
Leading indicators are convenient to analysis because of their relative large quantity. In a
turnaround environment, the numbers of accidents that occur are relatively few unlike the
number of near misses (Bird, 1980). It is easy to statistically analyze thirty at–risk behaviors than
four accidents. In addition Fleming et al (2001) noted that data from industry show much success
by companies in the reduction of accidents by efforts at reducing the number of at–risk behaviors,
increase the number of safety audits, and reduce the number of closed items from audits etc.
Phimister et al made similar claims when they said Near miss programs improve corporate
environmental, health and safety performance through the identification of near misses.
Existing literature also reveals many theories about management styles and their possible impact
on performance. The theories are grouped into trait theories, situational theories and behavioral
theories. The trait theories tries to explain management styles by traits of the managers like
initiative, wisdom, compassion and ambitious. Situational theories suggest that there is no best
management style and managers will need to determine which management style best suit the
situation. Behavioral theories explain management success by what successful managers do.
Behavioral theorists identify autocratic, benevolent, consultative and participatory management
styles. Vroom and Yetton (1973) identified variables that will determine the best management
style for any given situation. The variables are;
1. Nature of the problem. Is it simple, hard, complex or clear?
2. Requirements for accuracy. What is the consequence of mistakes?
3. Acceptance of an initiative. Do you want people to use their initiative or not?
4. Time–constraints. How much time do we have to finish the task?
5. Cost constraints. Do we have enough or excess to achieve the objective?
A decision model was developed by Vroom and Yago (1988)to help managers determine the best
management style for different situations based on the variables listed above (See figure six).
They also defined five management style could adopt, namely the;
1. Autocratic I style
2. Autocratic II style.
3. Consultative I style
4. Consultative II style
5. Group II style
The autocratic I management style is a management style where the leader solves the problem
alone using information that is readily available to him/her, is the normal management style of
the Escravos gas plant management in all turnarounds prior to 2009. However the Vroom and
Yago model recommends the Consultative II management style for the type of work done during
the Escravos gas plant turnaround maintenance.
According to Coye et al (1995), participatory management or consultative style II creates a sense
of ownership in organization. In this management style the leader shares problem with group
members individually, and asks for information and evaluation. Group members do not meet
collectively, and leader makes decision alone (Vroom and Yago, 1988). Coye et al believe that
this management styles instills a sense of pride and motivate employees to increase productivity.
In addition they stated that employees who participate in the decisions of the organization feel
like they are a part of a team with a common goal, and find their sense of self–esteem and
creative fulfillment heightened.
According to Filley et al (1961), Spector and Suttle did not find any significant difference in the
output of employees under autocratic and participatory management style.
This research studies if and how the Escravos gas plant turnaround maintenance can be improved
by changing the management style from autocratic I style to consultative II style. Two tasks in
the turnaround were studied; namely the change out of the molecular sieve catalyst beds and the
servicing of the turbine engines.
The turnaround contractor Techint Nigeria Limited divides the work group into teams
responsible for specific tasks. Six teams (team A, B, C, D, E and F) were studied. EGP
management will not allow the researcher to study more than these six teams for fear of the
research disrupting the work. The tasks completed by these teams are amongst those not on the projects critical path so delays caused by the research will not impact the entire turnaround
project provided the float on these activities were not exceeded. They also had the fewest number
of personnel, so cost impact of the research work could be easier to manager.
Teams A, B and C are different maintenance teams comprising of eight personnel each. They
were responsible for changing the EGP molecular sieve beds A, B and C respectively in the 2007
and 2009 turnaround. Their tasks are identical because the molecular sieve beds are identical.
Teams E, D and F are also maintenance teams comprising of six personnel each. They were
responsible for servicing the EGP turbine engines A, B and C during the 2007 and 2009
turnaround maintenance. Their tasks are also identical because the turbine engines are identical.
Consultative management style II is exercised by involving team A and team D in the
development of the procedures, processes and job safety analysis of all tasks that they were
assigned to complete during the 2009 turnaround maintenance. They were also permitted to
participate in the turnaround maintenance meetings and to make contributions in the meetings. In
the 2007 turnaround maintenance team A and team D only carried out their tasks. They did not
participate in the development of procedures and job safety analysis neither did they participate
in the turnaround maintenance meetings.
The other four teams; team B, team C, team E and team F are used as experimental controls for
the research. They did not participate in the development of the procedures, processes nor the job
safety analysis for the tasks in either of the turnaround maintenance. They were also not
permitted to attend the daily turnaround meetings. They only completed their tasks based on
instructions given to them during the 2007 and 2009 turnaround maintenance.
It was necessary to study the experimental control teams as the researcher was not sure whether
task repetition, increased knowledge or improved team cohesion would lead to a reduced time or
a reduced numbers of at–risk behavior.
ix
The research tested the hypothesis 1H0 and 1H1 and 2H0and 2H1 at the 0.025 and 0.05 level of
significance as follows;
Null hypothesis, 1H0: There is no significant difference in the time spent by team A and team
Din 2007 when they did not participate in the development of the procedures and processes with
the time in 2009 when they did(u1-u2=0).
Alternate hypothesis, 1H1: There is a significant difference in the time spent by the team A and
Din 2007 when they did not participate in the development of the procedures and processes with
the time in 2009 when they did (u1-u2!=0).
Null hypothesis, 2H0: There is no significant difference in the number of at–risk behaviors
observed to have been exhibited by the team A and team D in 2007 when they did not participate
in the development of the procedures and processes with the number in 2009 when they did (u1-u2=0).
Alternate hypothesis, 2H1: There is a significant difference in the number of at–risk behaviors
observed to have been exhibited by the team A and team D in 2007 when they did not participate
in the development of the procedures and processes with the number in 2009 when they did (u1-u2!=0).
The student t test was used to analyze these times and number of at–risk behavior. At the 0.025
and the 0.05 level of significance, the data show that there is no difference in the times all the
teams used to complete their task in 2007 and in 2009. The researcher concludes that a change in
the management style from autocratic I style to consultative II style did not lead to a reduction in
the time used by any team to complete their task.
However at the 0.025 and the 0.05 level of significance, there is a significant difference in the
number of at–risk behaviors of the research team A and team D. There is however no significant
difference in the number of at–risk behavior of the control team B, team C, team E and team F at
the same level of significance. The researcher concludes that a change in the management style from autocratic I style to consultative II style lead to a reduction in the number of at–risk
behavior of team A and team D.
In addition the reduction in the number of at–risk behavior of team A and team D could not have
been because of task repetition, increased knowledge or improved team cohesion since there is
no significant difference in the number of at–risk behavior exhibited by team B, team C, team E
and team F.
The research can be used by the Escravos gas plant management and the management of any
similar process plant to fashion out more cost effective, time effective and safer methods for
carrying out their turnaround maintenance. A change in management styles may just be a better
approach to improving productivity than giving financial incentives to contractors and personnel.
Changes in management style will have to be managed. The change must be gradual because
sudden change can be detrimental as people may just need to understand and adapt to the change.
The turnaround personnel must also understand the intent so as to prevent conflicts. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2012.
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Návrh a analýza systémů pokročilého zabezpečení a střežení objektů a prostor / Design and Analysis of Systems for Advanced Guarding and Securing Objects and AreasKomínek, Petr January 2011 (has links)
This diploma thesis deals with design, realization and analysis of security and surveillance systems for buildings and spaces containing advanced components. One of the main design's parts is dedicated to intruder alarm system, access system, attendance and CCTV systems with the possibility of automatic motion tracking. Controlling and monitoring of particular subsystems is possible both locally and remotely from a computer via a web interface or by means of a software. The access to camera system from a mobile phone is also possible. IAS/ACS systems also enable controlling and transferring information about their state via SMS. The designed system was realized completely and its operating was demonstrated. The realization is described in detail including illustration of configuration of particular components. A security analysis and a possible future development of the project is summarized in the conclusion.
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