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Desenvolvimento do sistema radicular e da parte aérea do feijoeiro comum em função da distribuição e do teor de fósforo no solo.; Effect of phosforus level, and its position in the soil, on the commom bean shoot and root system development.

Moreira, Miriam Ferraz
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 25/06/2004 PT
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O sistema radicular é indispensável para a obtenção de água e nutrientes do solo, síntese de reguladores de crescimento, e para o armazenamento de carboidratos. Embora seja indiscutível sua importância, esse órgão tem sido pouco estudado em relação a parte área. Provavelmente, em função da dificuldade de seu estudo, tendo em vista que seu desenvolvimento ocorre no solo, o que dificulta observações diretas. Consideramos de suma importância o desenvolvimento de métodos mais práticos, mais baratos, e que possibilitem avaliações rápidas, não destrutivas do sistema radicular. O conhecimento de uma estreita relação entre fitomassa fresca do sistema radicular e valor de capacitância, é antigo, mas na prática, é pouco empregado. Através do uso de um medidor manual de capacitância, visamos relacionar valores de capacitância com diversos parâmetros, tais como fitomassa seca, comprimento, área e respiração do sistema radicular de plantas do feijoeiro comum (Phaseolus vulgaris L.). Uma vez estabelecidas essas relações, é possível realizar medições com o capacitor para avaliar o desenvolvimento radicular, sob diferentes condições de disponibilidade de fósforo, de uma maneira rápida, prática e não destrutiva. A deficiência de fósforo...

A risk dynamics model of complex system development

Jootar, Jay, 1975-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 204 p.; 12801382 bytes; 12801142 bytes; application/pdf; application/pdf
ENG
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The development of complex systems is a challenging endeavor which has captured the attentions of scholars and practitioners alike. Throughout the decades, numerous methods have been proposed to help manage such development efforts more effectively and efficiently. Some of these methods, such as prototyping, concurrent engineering, iterative model for software development, and system-focused development for R&D, are process models which recommend better ways to structure the development process to handle the complexity of the system under development. This thesis seeks to understand the complex system development from a risk perspective. Continuing from the work done by other researchers, this work combines issues which are traditionally considered separately into one single model. More specifically, the model explicitly captures the dependencies in the system and the structure of an iterative development process and their interactions. The resulting mathematical problem demonstrates the risk characteristics of a development process. It shows that the optimality calls for a trade-off between the reduction of the probability of risk and the increase in the impact of risk. From its structure, the model also helps us understand how different aspects of system architecture affect the structure and the performance of the development process. In addition...

Using the design structure matrix to streamline automotive hood system development

Zambito, Antonino Paolo, 1970-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 80 leaves; 4894596 bytes; 4894354 bytes; application/pdf; application/pdf
ENG
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by Antonino Paolo Zambito.; Thesis (S.M.)--Massachusetts Institute of Technology, System Design & Management Program, 2000.; Includes bibliographical references (leaf 80).

Fire fighting in aerospace product development : a study of project capacity and resource planning in an aerospace enterprise

McQuarrie, Allan J. (Allan John), 1963-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 194 p.; 11926119 bytes; 11951099 bytes; application/pdf; application/pdf
ENG
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It is broadly recognized in the aerospace industry, as well as many others, that organizations which effectively execute development projects to meet desired cost, schedule, and performance targets for their customers produce higher levels of customer satisfaction and also a significant source of competitive advantage. Continually meeting the needs of the customer through effective project execution allows a company to become a preferred supplier favored in source selection for follow-on contracts and new development projects necessary for business growth. This research effort examines one aerospace company, which has multiple, diverse development projects on-going at any one time across several business units. The motivation for this thesis is to explore the product/system development capacity of the enterprise by analyzing the historical program performance of major projects, understanding the level of problem projects or fire fighting within the project pipeline, and the perceived causes of poor project performance. In addition, system dynamics models are developed to analyze the dynamics associated with project planning and resource planning strategies for both multi-project and single project scenarios. This analysis provides insight into the potential for project pipeline "tipping" and the effects of various project management and resource planning strategies in an aerospace product/system development context. Such analysis is believed to provide greater insight and opportunity to improve the product/system development performance for the enterprise.; by Allan J. McQuarrie...

9.14 Structure & Development of the Mammalian Brain, Spring 2002; Structure & Development of the Mammalian Brain

Schneider, Gerald E.
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
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EN-US
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Lectures plus guided readings and discussion with project reports, covering major CNS structures, with emphasis on systems being used as models for experimental studies of development and plasticity. Topics include: basic patterns of connections in CNS; review of lab techniques (anatomy, tissue culture); embryogenesis; PNS anatomy and development; process outgrowth and synaptogenesis; growth factors and cell survival; spinal and hindbrain anatomy; development of regional specificity with introduction to comparative anatomy and CNS evolution; trigeminal system; retinotectal system development, plasticity, regeneration; neocortex anatomy and development; olfactory system; corpus striatum; brain transplants; limbic system and hippocampal anatomy and plasticity.

Atributos físicos do solo, desenvolvimento radicular e produtividade de cana-de-açúcar em preparos de solo em áreas de renovação e expansão; Soil physical attributes, root system development and sugarcane yield under different soil tillages at renew and expansion area

Domingues, Luis Augusto da Silva
Fonte: Universidade Federal de Uberlândia Publicador: Universidade Federal de Uberlândia
Tipo: Tese de Doutorado
POR
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A cultura da cana-de-açúcar têm-se expandido para a região do Cerrado, promovendo a ocupação de áreas exploradas por pastagens e lavouras. Neste contexto, objetivou-se com este trabalho estudar os efeitos dos preparos de solo nos atributos físicos do solo, no desenvolvimento do sistema de raízes e na produtividade da cana-de-açúcar, em área de expansão e de renovação, no Cerrado brasileiro. O experimento foi conduzido em área de cana planta, entre o período de abril de 2009 e maio de 2010. Foram avaliados seis diferentes preparos de solo em cada área de estudo. Área de expansão: 1- arado aiveca + grade leve com dessecação (DAV); 2 - arado aiveca + grade leve sem dessecação (AVG); 3 - grade média + arado de aiveca + grade leve (PC); 4 - plantio direto (PD); 5 - subsolador (SU); 6 - grade média + arado de discos + grade leve (PCAd). Área de renovação: 1 - dessecação + arado aiveca + grade leve - (AVG), 2 - dessecação + plantio direto – (PD); 3 - dessecação + subsolador - (SU); 4 - subsolador + grade leve - (SUG); 5 - destruidor de soqueira + subsolador – (DsSU); 6 - destruidor de soqueira + grade média + arado de aiveca + grade leve – (DsPC). Os tratamentos foram implantados no momento da instalação do canavial...

Adaptive information system development

Vidgen, Richard; Wang, Xiaofeng
Fonte: University of Limerick Publicador: University of Limerick
Tipo: info:eu-repo/semantics/conferenceObject; all_ul_research; ul_published_reviewed
ENG
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peer-reviewed; Information system development (ISD) is being conducted in an increasingly turbulent and complex environment. New forms of ISD are emerging, such as open source software and agile methods but theory is needed to explain and help improve the organization of ISD. Complex Adaptive Systems (CAS) provides a novel perspective to understand and describe new forms of ISD and provide a theoretical foundation for researchers. This paper provides an overview of CAS and a review of its application to the study of organizations and to ISD. A directive approach to ISD is compared with a CAS informed approach, adaptive ISD. The CAS concept of coevolution is then used to throw light on the relationship between ISD and the enterprise in which the ISD activity takes place. The paper concludes with a research agenda for the application of CAS to ISD.

Tracking Results in Agriculture and Rural Development in Less-Than-Ideal Conditions : A Sourcebook of Indicators for Monitoring and Evaluation

Global Donor Platform for Rural Development; World Bank; Food and Agriculture Organization of the United Nations
Fonte: Global Donor Platform for Rural Development; World Bank; Food and Agriculture Organization of the United Nations Publicador: Global Donor Platform for Rural Development; World Bank; Food and Agriculture Organization of the United Nations
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The purpose of this sourcebook is to pull together into a single document a collection of common sense tips and recommendations based on actual practices and experience around the world. The sourcebook aims first and foremost to help strengthen Monitoring and Evaluation (M&E) capacity at the national and sub-national levels, and to ensure a consistency of approach and methodology so that, at the global level, sufficient reliable and timely information can be accessed from the different countries and used to make cross-country comparisons and to calculate development indicators at the global level. The sourcebook is specifically targeted towards countries where conditions are less-than-ideal, particularly with respect to the availability of relevant information. The sourcebook also shows how a service delivery approach can be used to select indicators which can generate useful, easy-to-measure early outcome measures. It suggests that greater use be made of qualitative indicators, such as access, use and satisfaction. The sourcebook devotes considerable attention to the need for a strong statistical infrastructure and reviews the range of different statistical instruments available.

Tracking Results in Agriculture and Rural Development in Less-Than-Ideal Conditions : A Sourcebook of Indicators for Monitoring and Evaluation

Global Donor Platform for Rural Development; World Bank; FAO Statistics Division
Fonte: Bonn: Global Donor Platform for Rural Development Publicador: Bonn: Global Donor Platform for Rural Development
EN_US
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The purpose of this sourcebook is to pull together into a single document a collection of common sense tips and recommendations based on actual practices and experience around the world. The sourcebook aims first and foremost to help strengthen Monitoring and Evaluation (M&E) capacity at the national and sub-national levels, and to ensure a consistency of approach and methodology so that, at the global level, sufficient reliable and timely information can be accessed from the different countries and used to make cross-country comparisons and to calculate development indicators at the global level. The sourcebook is specifically targeted towards countries where conditions are less-than-ideal, particularly with respect to the availability of relevant information. The sourcebook also shows how a service delivery approach can be used to select indicators which can generate useful, easy-to-measure early outcome measures. It suggests that greater use be made of qualitative indicators, such as access, use and satisfaction. The sourcebook devotes considerable attention to the need for a strong statistical infrastructure and reviews the range of different statistical instruments available.

Notes on Financial System Development and Political Intervention

Song. Fenghua; Thakor, Anjan
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
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The paper studies the impact of political intervention on a financial system that consists of banks and financial markets and develops over time. In this financial system, banks and markets exhibit three forms of interaction: they compete, they complement each other, and they co-evolve. Coevolution is generated by two new ingredients of financial system architecture relative to the existing theories: securitization and risk-sensitive bank capital. The authors show that securitization propagates banking advances to the financial market, permitting market evolution to be driven by bank evolution, and market advances are transmitted to banks through bank capital. Then they examine how politicians determine the nature of political intervention designed to expand credit availability. The authors find that political intervention in banking exhibits a U-shaped pattern, where it is most notable in the early stage of financial system development (through bank capital subsidy in exchange for state ownership of banks) and in the advanced stage (through direct lending regulation). Despite expanding credit access...

Notes on Financial System Development and Political Intervention

Song, Fenghua; Thakor, Anjan
Fonte: Oxford University Press on behalf of the World Bank Publicador: Oxford University Press on behalf of the World Bank
Tipo: Artigo de Revista Científica
EN_US
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We study the impact of political intervention on a financial system that consists of banks and financial markets and develops over time. In this financial system, banks and markets exhibit three forms of interaction: they compete, they complement each other, and they co-evolve. Co-evolution is generated by two new ingredients of financial system architecture relative to the existing theories: securitization and risk-sensitive bank capital. We show that securitization propagates banking advances to the financial market, permitting market evolution to be driven by bank evolution, and market advances are transmitted to banks through bank capital. We then examine how politicians determine the nature of political intervention designed to expand credit availability. We find that political intervention in banking exhibits a U-shaped pattern, where it is most notable in the early stage of financial system development (through bank capital subsidy in exchange for state ownership of banks) and in the advanced stage (through direct lending regulation). Despite expanding credit access, political intervention results in an increase in financial system risk and does not contribute to financial system evolution. Numerous policy implications are drawn out.

Motor system development of the preterm and low birthweight infant

Pitcher, J.; Schneider, L.; Drysdale, J.; Ridding, M.; Owens, J.
Fonte: W B Saunders Co Publicador: W B Saunders Co
Tipo: Artigo de Revista Científica
Publicado em //2011 EN
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Despite advances in knowledge and technology, accurate prediction of later neuromotor outcomes for infants born preterm remains somewhat elusive. Here we review some of the most recent findings regarding the differential effects of preterm birth and suboptimal fetal growth on neurodevelopment. Evidence from transcranial magnetic stimulation studies is presented that suggests neuromotor development may more directly influence cognitive outcomes than previously recognised. We discuss the role of neuroplasticity in both exacerbating and improving these postnatal outcomes, and possible therapeutic targets for manipulating this. Finally, some developmental care practices that might affect long-term outcomes for these children are discussed.; http://www.elsevier.com/wps/find/journaldescription.cws_home/623324/description#description; Julia B. Pitcher, Luke A. Schneider, John L. Drysdale, Michael C. Ridding and Julie A. Owens

Sox3 dosage regulation is important for roof plate specification during central nervous system development.

Lee, Kristie Pan Yu
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2011
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The central nervous system (CNS) is one of the most complicated organs in the body. Its development requires spatially and temporally dynamic but yet coordinated proliferation and differentiation of neural progenitors in order to allow the formation of the neural tube (NT) from a sheet-like neural plate, as well as the specification of different CNS domains from a homogeneous group of neural precursors. A number of genes have been identified to be important for the robust genetic and molecular regulation of the CNS development. One of these genes is SOX3, which encodes a SOX family transcription factor within a single exon. In humans, SOX3 duplications and mutations have been implicated in X-linked hypopituitarism (XH) with variable mental retardation, suggesting that CNS development is sensitive to SOX3 dosage. To recapitulate the condition in XH patients with SOX3 duplications, a transgenic Sox3 over-expression mouse model was generated in the Thomas laboratory. Two Sox3 transgenic lines were established. Intriguingly, they presented not with XH associated phenotypes, but with hallmarks of hydrocephalus. This thesis focuses on the characterisation of the hydrocephalus phenotype and the elucidation of the molecular pathogenesis that underlines the defect. Comprehensive morphological and expression analyses of single hemizygous and double hemizygous (mice with two transgene alleles...

Id genes in nervous system development

Andres-Barquin, P.J.; Hernandez, M.C.; Israel, M.A.
Fonte: Murcia : F. Hernández Publicador: Murcia : F. Hernández
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
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Id genes encode helix-loop-helix proteins that function to mediate processes important for normal development including cellular differentiation. proliferation and apoptosis. Id proteins act as negative regulators of other transcription factors, which are essential for cell determination and differentiation in diverse cell types, and interact with proteins important for cell cycle regulation. Studies of Id gene expression in the nervous system and in neural cells in culture indicate that Id proteins contribute to the regulation of mammalian nervous system development. Also, recognition of a wide variety of proteins with which Id transcription factors are capable of interacting suggests that it will be possible to understand more precisely their specific functions and importantly how these are integrated.

Configuration management for expert system development: application to the MK92 prototype Maintenance Advisor Expert System

Metzler, Paul Gregory.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: 187 p. :|bill.
EN_US
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The Naval Postgraduate School In conjunction with Port Hueneme Division (PHD), Naval Surface Warfare Center is developing a diagnostic expert system for troubleshooting casualties in the MK 92 MOD 2 fire control system deployed in US Navy Oliver Hazard class (FFG-7) guided missile frigates. The high turnover rate of student developers and the frequency with which changes are made to the expert system have highlighted a need for controlling the change process and the management of resources applied to implementing those changes to the expert system's knowledge base and software. This thesis develops a configuration management plan for the MK92 Maintenance Advisor Expert System (MK92 MAES) to assist object members in the management of changes to software and domain knowledge. The concept of configuration management is examined in detail with specific emphasis on the challenges of its implementation to expert systems. Two automated configuration management tools, CCC/Manager and PVCS Version Control, are evaluated for suitability for application in an expert system development environment. Finally, specific recommendations are presented for establishing a configuration management process for MK92 MAES project.; U.S. Navy (U.S.N.) author.

Nourishing Communities: Exploring the Relationships Between Local-Food-System Development and Community Capital

COURTNEY, SHANNON A
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
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Consumer concerns regarding food safety and quality, a crippling farm crisis across North America, and growing criticisms of the environmental consequences of intensive agricultural practices are leading to increased scrutiny of the dominant, industrialized food system. Faced with uncertainty, many communities are pioneering new, decentralized models of food production, with a view to designing systems that are more economically, ecologically and socially sustainable. At their essence, these local food systems appear to embody a new form of ‘capitalism’, one that values, depends upon, and seeks to strengthen or preserve all stocks of community capital: natural, human, social, and economic. Employing a case study approach, this research explores ways in which a local food system’s development depends upon the interplay of a community’s capital stocks, as well as ways in which a local food system may serve as a site for the creation or strengthening of these capital stocks, with a particular focus on social capital. The two communities studied are: Kingston, Ontario and Hardwick, Vermont. Both communities have been actively pursuing local-food system development through various initiatives. Face-to-face interviews, participant observations...

Understanding and managing uncertainty in lean aerospace product development

Bresnahan, Steven M. (Steven Michael)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 110 p.; 8005444 bytes; 8011807 bytes; application/pdf; application/pdf
ENG
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Aspects of aircraft product uncertainty during system development are examined. Generation of stakeholder value in lean aerospace product development is linked to the reduction or elimination of project risks and uncertainties in areas such as customer requirements, product performance, and issues that may arise later in the product's life cycle. A commercial aircraft system project is explored as a case study. The system is comprised a numerous subsystems developed by separately managed teams. Teams had different approaches to risk identification and mitigation. The relative success of each team is summarized. A framework for creating value by efficiently and effectively managing uncertainty and mitigating risks during aerospace system development is presented.; by Steven M. Bresnahan.; Thesis (S.M.)--Massachusetts Institute of Technology, System Design and Management Program, 2006.; Includes bibliographical references (p. 84-98).

Development of a system dynamics based management flight simulator for new product development

MacInnis, Daniel V., 1964-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 198 p.; 11637785 bytes; 11663154 bytes; application/pdf; application/pdf
ENG
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All firms in any mature product development industry are being pressured into performing 'better, faster, and cheaper' by both customers and competitors. In short, firms are being tasked with doing more, with less, faster. This leads to product development organizations being unrealistically tasked to deliver on these programs that often lead to projects falling behind schedule, over budget, and with inadequate quality. While striving to do the right actions to survive, the management of these firms may be leading their firms to disaster through over commitment, and short-term management actions to address the quality, budget, and schedule shortfalls. An understanding of the system dynamics associated with the program management of new product development (NPD) programs is essential to reversing this trend. Several corporations are instituting system dynamics in their management and executive training curricula to affect correct policies, procedures, and behaviors that lead to success. However, because the correct policies, procedures, and behaviors as revealed by system dynamics analysis are counter-intuitive and opposite those policies currently employed in program management, a method is needed to drive the learning of system dynamics so that it becomes ingrained in the program management thought processes. A management flight simulator (MFS) of the program management of a new product development project based on system dynamics provides the hands on experience that managers can learn the consequences of non systems-thinking policies on project performance and how system dynamics based policies can lead to greater success. This thesis provides an overview of the system dynamics of project management in new product development and insight into the; (cont.) correct policies...

System theoretic framework for assuring safety and dependability of highly integrated aero engine control systems

Atherton, Malvern J
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 120 p.; 6847448 bytes; 6854854 bytes; application/pdf; application/pdf
ENG
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The development of complex, safety-critical systems for aero-engine control is subject to the, often competing, demands for higher safety and reduced development cost. Although the commercial aerospace industry has a general good safety record, and has placed much emphasis on process improvement within a strong safety culture, there continues to be a large number of design and requirements errors found during development and after entry into service. 'The thesis assesses current system safety practice within the aero engine control system industry, including international standards, and reviews the current practice against the research at MIT by Professor Nancy Leveson. The thesis focuses in particular on software safety as this is the area that has proven most challenging and most likely to experience high costs. The particular research topics reviewed are Intent Specifications, the System Theoretic Accident Modeling and Processes (STAMP) technique, and requirements completeness criteria. Research shows that many problems arise from requirements and design errors rather than component failures. Several example incidents from an engine company are reviewed and these show a pattern of common problems which could have been caught by the use of more comprehensive requirements completeness checks and by the use of Intent Specifications. In particular...

Review of Relevant System Development Life Cycles (SDLCs) in Service-Oriented Software Engineering (SoSE)

Rodríguez-Martínez,L.; Mora,M.; Álvarez,F.; Garza,L.; Durán,H.; Muñoz,J.
Fonte: UNAM, Centro de Ciencias Aplicadas y Desarrollo Tecnológico Publicador: UNAM, Centro de Ciencias Aplicadas y Desarrollo Tecnológico
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2012 EN
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Service-oriented software engineering (SoSE) is a new paradigm for building software systems, fostered by the availability of a new -but already mature- computing technology based on services. SoSE advances the current object-oriented and the component-based software engineering paradigms. Under that new paradigm, multiple software-system development life cycle (SDLC) methodologies have been proposed; however, none of them have gained a total acceptance as the dominant SDLC in SoSE. On this theoretical and practical situation, we believe that a research is required to reach more standardized and stabilized knowledge about SDLCs in SoSE. Thus, this article reviews nine recent SDLCs proposed for SoSE with the aim to present a descriptive-comparative landscape of a relevant range of SDLCs for SoSE. Such description-comparison is guided by two criteria: (i) the extent of completeness of each SDLC, with respect to the proposed phases, activities and delivered artifacts, and (ii) the extent of the Boehm-Turner's Rigor-Agility balance. Our results suggest that only three of the nine SDLCs studied already provide the best level of completeness and Rigor-Agility. Finally, we consider that the reported descriptive-comparative framework and their findings from each SDLC can be useful also for comparing and elaborating future SDLCs in SoSE.