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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.
11

Estratégias de aplicação de análise estatística multivariada no desenvolvimento de novos produtos

Silveira, Manoel Mendonça January 2010 (has links)
No processo de desenvolvimento de novos produtos e serviços, o entendimento de quais demandas são exigidas pelo mercado conduz ao desenvolvimento de projetos com melhores soluções aos clientes. Na busca deste entendimento, técnicas estatísticas multivariadas são utilizadas como suporte para identificar e valorar os requisitos derivados destas demandas. Nesse contexto, o objetivo deste trabalho é apresentar uma abordagem para aplicação de técnicas estatísticas multivariadas no processo de desenvolvimento de novos produtos (PDP). Estas técnicas podem auxiliar as empresas no gerenciamento de requisitos, contribuindo para: (i) coletar e organizar os requisitos do produto; (ii) identificar os requisitos considerados como mais relevantes; (iii) identificar os segmentos de mercado baseado nas características valoradas pelo público-alvo; (iv) verificar associações entre requisitos de um produto e determinadas características do público-alvo. Este trabalho apresenta um exemplo de aplicação contemplando o uso combinado de técnicas estatísticas tais como o método CHAID (Chi-squared Automatic Interaction Detector), análise fatorial, análise conjunta de atributos e análise de correspondência. A demonstração do emprego destas técnicas é realizada no desenvolvimento de um novo produto de limpeza doméstica produzido com características de sustentabilidade. / The deep understanding of market’s requirements, during the manufacturing of new products and/or services, leads to the creation of products of better configuration attend customers’ necessities. Multivariable analysis techniques can be employed to help identifying such consumer preferences. Therefore, the aim of this study is to illustrate an approach to the employment of multivariate statistical procedures on the development of new products (DNP). These techniques can assist companies in managing products’ requirements by helping them to: (i) assemble and categorize products’ requirements; (ii) identify those requirements considered more relevant among all; (iii) identify market sectors based on the aspects most valuable to consumers; (iv) check on associations between one given product and certain features of general customers. The present work illustrates the combined use of statistical techniques such as the CHAID (Chi-squared Automatic Interaction Detector), factorial analysis, conjoint analysis and correspondence analysis. The successful application of these techniques is exemplified with the development of a new domestic cleaning environmental-friendly product.
12

Estudo, análise e proposta de diretrizes a serem consideradas no projeto do produto óculos para o público infantil / Study, analysis and proposal of guidelines to consider in product design glasses for children

Chaves, Iana Garófalo 17 December 2014 (has links)
Os óculos se destacam por sua função social no atendimento das necessidades humanas, se considerados os indivíduos que dependem deste produto em sua condição de órtese. Este trabalho considera que para o público infantil, o projeto do produto de armações, demanda estudos e pesquisas, para propor resoluções técnicas, formais e estéticas adequadas, mas, sobretudo para captar os aspectos perceptivos, subjetivos e emocionais, que despertem a afeição desse segmento social com este objeto. A pesquisa teve como principal objetivo a definição e proposta de diretrizes para auxiliar no projeto do produto óculos para o público infantil. Para isto, foram utilizadas abordagens metodológicas do design, que consideram os indivíduos envolvidos como elementos centrais no processo do projeto, a exemplo do Design Centrado no Humano (DCH), adotado como estratégia fundamental no enfoque desta dissertação.A pesquisa presenta um levantamento histórico sobre o produto óculos e sobre as normas já existentes para o seu projeto; além de uma revisão sobre as abordagens metodológicas de design centradas nos indivíduos; e as coletas de dados considerando as crianças usuárias de óculos de 6 a 11 anos e as seguintes partes envolvidas, ou seja, os stakeholders - os responsáveis ou cuidadores; os oftalmopediatras e os atendentes das óticas. Para cada grupo foi definido um método a ser aplicado, com intuito de coletar informações sobre as diferentes visões do produto, considerando principalmente os aspectos emocionais e comportamentais envolvidos nas relações das crianças com as armações. Foram utilizados os procedimentos de storytelling e \'prototipar para empatia\', aplicados com as crianças; entrevistas individuais realizadas com oftalmopediatras e atendentes de óticas; e questionários com os cuidadores. A análise e a discussão dos resultados obtidos em cada um dos métodos foram confrontadas através de relações de triangulação, contribuindo para elencar as diretrizes para o projeto das armações, com conteúdose aspectos objetivos e subjetivos, referendando o uso das metodologias adotadas, e desta perspectiva de aproximação com as emoções de desejos das crianças em relação aos seus óculos, como fundamentais para a atuação em design de produto. / The glasses stands out for their social function in the attendance of human needs, if we consider whom depends on this product in orthoses condition. This research considered for the children audience, the demand for glasses design studies and research to propose technical, formal and appropriate aesthetic resolutions, but, especially to capture the perceptual, subjective and emotional aspects that arouse affection of this social segment with this object. The research aimed to define and propose guidelines to design glasses for children. The methodological approaches adopted considered the user and the individuals involved in the process as central elements in the design process, such as the study of Human Centered Design (HCD). The research presents historical study on the glasses and the existing standards for its project; the design methodologies geared to individuals, and the data collection considering children whom wear glasses of 6 to 11 years and the following third parties involved called stakeholders - the adults caregivers; the pediatric ophthalmology and the optical attendants. For each stakeholder was defined a method to be applied, aiming to collect information about the different views of the product, especially considering the emotional and behavioral relationships involved in children\'s issues with the frames. For the children were applied two methods, the storytelling and prototype for empathy; the individual interviews method was applied with pediatric ophthalmology and optical attendants and questionnaire method was applied with caregivers. The analysis and discussion of the results obtained in each method was compared using triangulation relationship, contributing to define the guidelines for design children glasses, based on the adopted methodology the guidelines has objective and subjective aspects in its contents, approaching of the children\'s emotions and wishes regarding their glasses, a very important issue for design this product.
13

A strategic planning methodology for aircraft redesign

Romli, Fairuz Izzuddin 06 April 2009 (has links)
Due to a progressive market shift to a customer-driven environment, the influence of engineering changes on the product's market success is becoming more prominent. This situation affects many long lead-time product industries including aircraft manufacturing. Derivative development has been the key strategy for many aircraft manufacturers to survive the competitive market and this trend is expected to continue in the future. Within this environment of design adaptation and variation, the main market advantages are often gained by the fastest aircraft manufacturers to develop and produce their range of market offerings without any costly mistakes. This realization creates an emphasis on the efficiency of the redesign process, particularly on the handling of engineering changes. However, most activities involved in the redesign process are supported either inefficiently or not at all by the current design methods and tools, primarily because they have been mostly developed to improve original product development. In view of this, the main goal of this research is to propose an aircraft redesign methodology that will act as a decision-making aid for aircraft designers in the change implementation planning of derivative developments. The proposed method, known as Strategic Planning of Engineering Changes (SPEC), combines the key elements of the product redesign planning and change management processes. Its application is aimed at reducing the redesign risks of derivative aircraft development, improving the detection of possible change effects propagation, increasing the efficiency of the change implementation planning and also reducing the costs and the time delays due to the redesign process. To address these challenges, four research areas have been identified: baseline assessment, change propagation prediction, change impact analysis and change implementation planning. Based on the established requirements for the redesign planning process, several methods and tools that are identified within these research areas have been abstracted and adapted into the proposed SPEC method to meet the research goals. The proposed SPEC method is shown to be promising in improving the overall efficiency of the derivative aircraft planning process through two notional aircraft system redesign case studies that are presented in this study.
14

Estudo, análise e proposta de diretrizes a serem consideradas no projeto do produto óculos para o público infantil / Study, analysis and proposal of guidelines to consider in product design glasses for children

Iana Garófalo Chaves 17 December 2014 (has links)
Os óculos se destacam por sua função social no atendimento das necessidades humanas, se considerados os indivíduos que dependem deste produto em sua condição de órtese. Este trabalho considera que para o público infantil, o projeto do produto de armações, demanda estudos e pesquisas, para propor resoluções técnicas, formais e estéticas adequadas, mas, sobretudo para captar os aspectos perceptivos, subjetivos e emocionais, que despertem a afeição desse segmento social com este objeto. A pesquisa teve como principal objetivo a definição e proposta de diretrizes para auxiliar no projeto do produto óculos para o público infantil. Para isto, foram utilizadas abordagens metodológicas do design, que consideram os indivíduos envolvidos como elementos centrais no processo do projeto, a exemplo do Design Centrado no Humano (DCH), adotado como estratégia fundamental no enfoque desta dissertação.A pesquisa presenta um levantamento histórico sobre o produto óculos e sobre as normas já existentes para o seu projeto; além de uma revisão sobre as abordagens metodológicas de design centradas nos indivíduos; e as coletas de dados considerando as crianças usuárias de óculos de 6 a 11 anos e as seguintes partes envolvidas, ou seja, os stakeholders - os responsáveis ou cuidadores; os oftalmopediatras e os atendentes das óticas. Para cada grupo foi definido um método a ser aplicado, com intuito de coletar informações sobre as diferentes visões do produto, considerando principalmente os aspectos emocionais e comportamentais envolvidos nas relações das crianças com as armações. Foram utilizados os procedimentos de storytelling e \'prototipar para empatia\', aplicados com as crianças; entrevistas individuais realizadas com oftalmopediatras e atendentes de óticas; e questionários com os cuidadores. A análise e a discussão dos resultados obtidos em cada um dos métodos foram confrontadas através de relações de triangulação, contribuindo para elencar as diretrizes para o projeto das armações, com conteúdose aspectos objetivos e subjetivos, referendando o uso das metodologias adotadas, e desta perspectiva de aproximação com as emoções de desejos das crianças em relação aos seus óculos, como fundamentais para a atuação em design de produto. / The glasses stands out for their social function in the attendance of human needs, if we consider whom depends on this product in orthoses condition. This research considered for the children audience, the demand for glasses design studies and research to propose technical, formal and appropriate aesthetic resolutions, but, especially to capture the perceptual, subjective and emotional aspects that arouse affection of this social segment with this object. The research aimed to define and propose guidelines to design glasses for children. The methodological approaches adopted considered the user and the individuals involved in the process as central elements in the design process, such as the study of Human Centered Design (HCD). The research presents historical study on the glasses and the existing standards for its project; the design methodologies geared to individuals, and the data collection considering children whom wear glasses of 6 to 11 years and the following third parties involved called stakeholders - the adults caregivers; the pediatric ophthalmology and the optical attendants. For each stakeholder was defined a method to be applied, aiming to collect information about the different views of the product, especially considering the emotional and behavioral relationships involved in children\'s issues with the frames. For the children were applied two methods, the storytelling and prototype for empathy; the individual interviews method was applied with pediatric ophthalmology and optical attendants and questionnaire method was applied with caregivers. The analysis and discussion of the results obtained in each method was compared using triangulation relationship, contributing to define the guidelines for design children glasses, based on the adopted methodology the guidelines has objective and subjective aspects in its contents, approaching of the children\'s emotions and wishes regarding their glasses, a very important issue for design this product.
15

Towards a guided framework for innovative engineering through the generation and evaluation stages of concept design

Oman, Sarah Kay 13 June 2012 (has links)
This work proposes a framework of concept generation and evaluation that takes into consideration the benefit of creativity and innovation in current market trends. By educating engineers in how to increase creativity in concept design and assess it quantitatively, the next generation of designers will be a step ahead of the market. This research begins with an in-depth survey of current creativity assessment methods in engineering in order to determine where the limitations currently lie in this field of study. The limitations discovered based on this unique analysis were used as motivation for the development of the proposed creativity assessment method. Specifically, we introduce a set of metrics that break down concepts to their component and subfunction level to assess the novelty and quality of component solutions ��� called the Comparative Creativity Assessment (CCA) Method. Secondly, we break down market-tested innovative products to isolate innovation information to utilize in concept generation inspiration ��� called the Repository of Innovative Products (RIP). Finally, revisions to the initial CCA method and RIP are proposed and analysis of past data results are compared to the new revised results. Revisions to the CCA method include additional metrics that factor in interaction effects from function pairing and component assemblies deemed innovative as well as eliminate evaluator subjectivity in the analysis. Observations from the experiments conducted are presented in a Lessons Learned chapter. / Graduation date: 2013
16

An Approach to Decision Support for Strategic Redesign

Chamberlain, Matthew Kipp 15 November 2007 (has links)
Researchers have paid relatively little attention to the fact that most design activities are actually more like redesign. These activities are characterized by an attempt to leverage experience, knowledge, and the capital that a company has already invested into existing engineering systems. In this dissertation, it is proposed that an approach be developed to aid designers in making decisions in redesign problems when there exist systems to be leveraged and multiple new systems to be created. In addition, strategy is introduced to the problem through the consideration that new systems may not be offered all at once, as is often assumed in product family design research. In this dissertation, the aim of the designer is assumed to be a creation, through redesign, of a series of new systems with desirable and distinct performance levels. In addition, a plan is required to involve as little redesign effort throughout the life of the family of systems as possible The proposed approach is based upon the concepts of Constructal Theory and previous work to create methods for the design of mass customized families of products. The existing methods are abstracted and heavily modified through the infusion of the compromise Decision Support Problems at all stages of the decision-making process. In addition, two indices are developed to represent considerations unique to redesign as opposed to original design. These indices for redesign effort and commonality value are utilized in the overall objective formulation for the approach. Through a thorough validation process and a large number of redesign scenarios, it is shown that the overall approach proposed can lead the designer towards promising redesign plans involving leveraging of existing systems, but that the constructal-inspired approach in and of itself has certain limitations when applied to redesign.
17

Virtual prototyping of an articulated dump truck.

Govender, Deena. January 2003 (has links)
In the modem automotive industry product times to market are being increasingly compressed. In the earthmoving and construction machine industry this is also true with the manufacturer having to respond to new customer requirements quickly and decisively. Virtual prototyping is a vital tool in the vehicle engineer's armoury, allowing a large portion of developmental investigation to be done on the virtual model with the attendant savings in time and cost and allowing often dangerous manoeuvres to be predicted and investigated prior to actual physical prototype testing. The University of Natal BELL Equipment collaborative effort involves the vehicle dynamics modelling and model validation of a BELL Equipment manufactured B40C Articulated Dump Truck (ADT). The modelling was completed using the multibody system (MBS) simulation software package, ADAMS. Initial modelling and simulation results are presented with specific attention paid to the introduction of valid data for compliant joints in the MBS as well as modelling of the tire. The physical testing of the ADT is also presented as well as a discussion of the data acquisition system. Key results from the physical testing of the ADT are also presented and discussed. / Thesis (M.Sc.Eng.)-University of Natal,Durban, 2003.
18

Setting up a backtrack-free customisation process for product families = Estabelecendo um processo de customização livre de retrocessos para famílias de produtos / Estabelecendo um processo de customização livre de retrocessos para famílias de produtos

Schneider, Homero Mauricio, 1953- 25 August 2018 (has links)
Orientador: Yuzo Iano / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-25T04:44:14Z (GMT). No. of bitstreams: 1 Schneider_HomeroMauricio_D.pdf: 3315215 bytes, checksum: 24f2739a680bd64590516d28c5900606 (MD5) Previous issue date: 2014 / Resumo: Um conceito chave na área de customização em massa é o de família de produtos. Embora o projeto de uma família de produtos é uma tarefa difícil e desafiadora, derivar os membros da família de produtos para atender os requisitos de clientes individuais pode ser uma tarefa de design rotineira. Neste trabalho, propomos uma abordagem formal para modelar o processo de customização de famílias de produtos, que alcançar este objetivo. De fato, construímos uma teoria para a customização de famílias de produtos. Esta abordagem é baseada em uma estrutura de conhecimento para a representação de famílias de produtos que combina uma estrutura de produto genérica e uma rede de restrições estendida com funções de design. O método para derivar os membros da família de produtos é um processo de instanciação com duas fases. Primeiramente, uma solução para o modelo de rede de restrição consistente com os requisitos do cliente é encontrada. Em seguida, esta solução é utilizada para transformar a estrutura de produto genérica em uma estrutura especifica que corresponde a um membro da família de produtos. Neste trabalho, provamos que, se o modelo de rede de restrição estendida com funções de design satisfaz algumas condições de modelagem, então encontrar soluções se torna um processo livre de retrocessos. Embora existam outros trabalhos na literatura que também afirmam ser livre de retrocessos, um fato notável sobre a nossa abordagem é que conseguimos isso através da introdução de conhecimento sobre a família de produtos, em vez de recorrer ao poder computacional e pré-processamento como naquelas abordagens. Outro aspecto notável da nossa abordagem é que os componentes podem ser projetados como parte do processo de personalização através das funções de design. Isto implica que é possível dispor de um processo de customização eficiente sem comprometer a flexibilidade da família de produtos. Na conclusão deste trabalho, argumentamos que a nossa abordagem pode lidar com problemas de customização que estão fora da área de configuração de produtos. Dois apêndices também são adicionados à tese. Um deles é uma modelagem completa de uma família de produtos Chave de Transferência Automática (ATS) baseado em nossa abordagem. Este exemplo é usado no corpo principal da tese para ilustrar os conceitos que estão sendo introduzidos. A outra é uma implementação computacional do primeiro estágio do processo de customização da família de produtos ATS / Abstract: Product family is a key concept is the area of mass customisation. Although the design of a product family is a difficult and challenging task, to derive members of the product family to meet the requirements of individual customers can be a routine design task. In this work, we propose a formal approach to model the customisation of product families that achieves this goal. In fact, we are setting up a theory for the customization of product families. This approach is based on a knowledge framework for the representation of product families, which combines a generic product structure and a constraint network extended with design functions. The method for deriving members of the product family is a two-stage instantiation process. First, a solution to the constraint network model consistent with the customer requirements is found. Next, this solution is used to transform the generic product structure into a specific structure that corresponds to a member of the product family. In this work, we prove that if the constraint network model extended with design functions satisfies a few modelling conditions, then to find solutions become a backtrack-free process. Although there are other works in the literature that also claim to be backtrack-free, a remarkable fact about our approach is that we achieve this by the introduction of knowledge about the product family, instead of resorting to computational power and pre-processing as in those approaches. Another remarkable aspect of our approach is that components can be designed as part of the customisation process using the design functions. This implies that it is possible to have an efficient customisation process without compromising the flexibility of the product family. In the conclusion of this work, we argue that our approach can deal with customisation problems outside the product configuration area. Two appendixes are also added to the thesis. One is a compete modelling of the Automatic Transfer Switch (ATS) product family using our approach. This example is used in the main body of the thesis to illustrate the concepts that are being introduced. The other one is the computational implementation of the first-stage customisation process of the ATS product family / Doutorado / Telecomunicações e Telemática / Doutor em Engenharia Elétrica
19

Ciclos de desenho: uma percep??o dos ciclos de economia e tecnologia

Borges, Ana L?gia do Lago 25 February 2016 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-09-27T00:02:12Z No. of bitstreams: 1 AnaLigia_Disserta??o_completa.pdf: 3275012 bytes, checksum: 3fbf17a121f3ccc63ae9e4e137889710 (MD5) / Made available in DSpace on 2016-09-27T00:02:12Z (GMT). No. of bitstreams: 1 AnaLigia_Disserta??o_completa.pdf: 3275012 bytes, checksum: 3fbf17a121f3ccc63ae9e4e137889710 (MD5) Previous issue date: 2016-02-25 / This dissertation deals an analysis of the cyclical changes of the design of industrial products, its relations with long cycles of economy and technology and its implications for local material culture. This research was conducted based on the model used by Langrish, work published in England in 1982. In his work, examine published magazines advertisements, with an emphasis on motivational spirit of society. We questioned if the Brazil, as a semi-peripheral country, has optimism cycles in design as it appears in England. The main objective is the analysis of how behaves the motivation of products design in the country, between the cyclical fluctuations of economy and technology. To achieve our goals was carried out an analysis of selected periods announcements in accordance with the variation of the national political-economic framework of the VEJA Magazine, between 1968 to 2015 years. After evaluating the results, this research reveals the perception of cyclical changes the products design in function of changes techno-economics paradigms and a heavy reliance of the design produced in the leading countries economically. In chapter one, the introduction to the survey is presented. The chapter two provides a brief historical and theoretical overview of the design, the economic cycles and technological changes. In the third chapter, we discuss the design changes opportunities and the economic situation of the peripheral countries. Analyzes and contributions is in the fourth chapter. In the fifth chapter are cited some final considerations of the research. / sta disserta??o faz uma an?lise sobre as mudan?as c?clicas do Desenho de produtos industrializados, suas rela??es com os ciclos longos de economia e tecnologia e o que isto implica como cultura material local. A pesquisa foi realizada com base no modelo utilizado por Langrish, em 1982, em seu artigo publicado na Inglaterra, que consiste em analisar imagens dos an?ncios de revistas ou peri?dicos publicados, com ?nfase no esp?rito motivacional da sociedade. Questionamos se o Brasil, como um pa?s semiperif?rico, possui Ciclos de otimismo em Desenho tal qual apresentado na Inglaterra. O objetivo principal ? a an?lise de como se comporta a motiva??o do desenho de produtos, no Pa?s, entre as oscila??es c?clicas de economia e tecnologia. Para atingir nossos objetivos foi realizada uma an?lise dos an?ncios de per?odos selecionados em conformidade com a varia??o do quadro pol?ticoecon?mico nacional, da Revista VEJA, entre os anos de 1968 a 2015. Ap?s os resultados auferidos, a pesquisa revela a percep??o das mudan?as c?clicas do desenho de produtos em fun??o das mudan?as dos paradigmas tecnoecon?micos no Pa?s e uma forte depend?ncia de desenhos produzidos em pa?ses l?deres economicamente. No cap?tulo um, encontra-se a parte introdut?ria da pesquisa. O cap?tulo dois traz um breve panorama hist?rico e te?rico sobre o Desenho, os Ciclos Econ?micos e as mudan?as tecnol?gicas. No terceiro cap?tulo, abordamos as oportunidades de mudan?as do Desenho e da situa??o econ?mica dos pa?ses perif?ricos. As an?lises e contribui??es, fruto da pesquisa, encontra-se no quarto cap?tulo. No quinto cap?tulo as considera??es finais da pesquisa.
20

Essays on Disability: Consumer Needs, Tradeoffs, and New Product Design

Malter, Maayan January 2024 (has links)
This dissertation advocates for greater recognition and inclusion of the large and growing population of disabled people as an integral part of the marketplace and in marketing research. Three trends are converging that increase the imperative to focus more attention on disability in the marketplace: demographics, inclusion, and technology. The experience of disabled consumers in the marketplace is fundamentally different from that of able-bodied consumers and has implications for all stakeholders in marketing. To better understand the heart of this matter, Essay 1 develops a theoretical framework to explain how disabled individuals approach consumption decisions. They must choose between three coping strategies (self-initiative, social support, and assistive technology) to overcome the challenges of their disability and achieve their consumption goals. In doing so, they face an inherent and constant tradeoff of fulfilling a need for autonomy versus need for efficiency. No strategy fulfills both, rather each facilitates one while hindering the other, creating tension between competing goals. This tradeoff is typically not faced by able-bodied consumers, who are able to achieve both autonomy and efficiency on the same task. Essay 2 empirically and experimentally tests one aspect of the theoretical framework, namely how observers may perceive (or misperceive) the needs of people with physical disabilities, identifies inaccurate perceptions that may lead to suboptimal outcomes, and examines how these perceptions can be leveraged to improve outcomes. Although I advocate a fully inclusive design approach, in which people with disabilities are integral to decision making processes affecting them, the current reality is that many decisions are still made on their behalf by others. As a result, marketers, product designers, policy makers, and individuals need to understand the needs of people with disabilities to create, market, and support products that better fulfill those needs. In contrast to prior research on dehumanization, which finds that observers diminish the importance of high-order (psychological) needs of “othered” groups, I find that observers elevate the importance of high-order needs of people with physical disabilities to compensate for perceived physical challenges. Across eight studies, I identify this systematic bias and resulting consequential decisions in the realm of product design and response to marketing campaigns. I conclude by discussing implications of these findings for managers, public policy, and future research.

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