Social Network Structure as a Critical Success Condition for Open Source Software Project Communities

In recent years, a surprising new phenomenon has emerged in which globally-distributed online communities collaborate to create useful and sophisticated computer software. These open source software groups are comprised of generally unaffiliated individuals and organizations who work in a seemingly chaotic fashion and who participate on a voluntary basis without direct financial incentive. The purpose of this research is to investigate the relationship between the social network structure of these intriguing groups and their level of output and activity, where social network structure is defined as 1) closure or connectedness within the group, 2) bridging ties which extend outside of the group, and 3) leader centrality within the group. Based on well-tested theories of social capital and centrality in teams, propositions were formulated which suggest that social network structures associated with successful open source software project communities will exhibit high levels of bridging and moderate levels of closure and leader centrality. The research setting was the SourceForge hosting organization and a study population of 143 project communities was identified. Independent variables included measures of closure and leader centrality defined over conversational ties, along with measures of bridging defined over membership ties. Dependent variables included source code commits and software releases for community output, and software downloads and project site page views for community activity. A cross-sectional study design was used and archival data were extracted and aggregated for the two-year period following the first release of project software. The resulting compiled variables were analyzed using multiple linear and quadratic regressions, controlling for group size and conversational volume. Contrary to theory-based expectations, the surprising results showed that successful project groups exhibited low levels of closure and that the levels of bridging and leader centrality were not important factors of success. These findings suggest that the creation and use of open source software may represent a fundamentally new socio-technical development process which disrupts the team paradigm and which triggers the need for building new theories of collaborative development. These new theories could point towards the broader application of open source methods for the creation of knowledge-based products other than software.

Diversity of Hymenoptera, Cultivated Plants and Management Practices in Home Garden Agroecosystems, Kyrgyz Republic

Pollination-dependent fruit trees grown in home gardens play an important role in the agricultural based economy of Central Asian countries, yet little is known about the status of pollinator communities, the cultivated plant composition or the factors that influence management practices in Kyrgyz home garden agroecosystems. As agricultural systems are human created and managed, a logical approach to their study blends anthropological and ecological methods, an ethnoecological approach. Over three years, I investigated how species richness and abundance of Hymenoptera, cultivated plants, and home garden management were related using quantitative and qualitative methods in the Issyk-kul Man and Biosphere reserve. Structured surveys were undertaken with heads of households using a random sample stratified by village. Gardens were then mapped with participation of household members to inventory edible species in gardens, most of which are pollinator-dependent, and to compare home garden diversity as reported by respondents during interviews. Apple diversity was studied to the variety level to understand respondents’ classification system in the context of in situ agrobiodiversity conservation. Household members identified 52 edible plant species when mapping the garden, compared with 32 reported when interviewed. The proportion of plant species received from others through exchange and the number of plots cultivated significantly explained the variation in edible plant diversity among gardens. Insects were sampled in gardens and orchards to determine potential pollinator community composition and the effect of different management practices on Hymenoptera richness and abundance. I collected 756 Hymenoptera individuals (56 bee; 12 wasp species); 12 species were new records for Kyrgyzstan or within Kyrgyzstan. Economic pressures to intensify cultivation could impact management practices that currently promote diversity. A home garden development initiative was undertaken to study management practice improvement. Participants in the initiative had higher adoption rates than controls of management practices that improve long-term yield, ecological sustainability and stability of home gardens. Home gardens, as currently managed, support abundant and diverse pollinator communities and have high cultivated plant diversity with few differences in community composition between garden management types.

Design and evaluation of a consulting system for database design

Database design is a difficult problem for non-expert designers. It is desirable to assist such designers during the problem solving process by means of a knowledge based (KB) system. Although a number of prototype KB systems have been proposed, there are many shortcomings. Firstly, few have incorporated sufficient expertise in modeling relationships, particularly higher order relationships. Secondly, there does not seem to be any published empirical study that experimentally tested the effectiveness of any of these KB tools. Thirdly, problem solving behavior of non-experts, whom the systems were intended to assist, has not been one of the bases for system design. In this project, a consulting system, called CODA, for conceptual database design that addresses the above short comings was developed and empirically validated. More specifically, the CODA system incorporates (a) findings on why non-experts commit errors and (b) heuristics for modeling relationships. Two approaches to knowledge base implementation were used and compared in this project, namely system restrictiveness and decisional guidance (Silver 1990). The Restrictive system uses a proscriptive approach and limits the designer's choices at various design phases by forcing him/her to follow a specific design path. The Guidance system approach, which is less restrictive, involves providing context specific, informative and suggestive guidance throughout the design process. Both the approaches would prevent erroneous design decisions. The main objectives of the study are to evaluate (1) whether the knowledge-based system is more effective than the system without a knowledge-base and (2) which approach to knowledge implementation - whether Restrictive or Guidance - is more effective. To evaluate the effectiveness of the knowledge base itself, the systems were compared with a system that does not incorporate the expertise (Control). An experimental procedure using student subjects was used to test the effectiveness of the systems. The subjects solved a task without using the system (pre-treatment task) and another task using one of the three systems, viz. Control, Guidance or Restrictive (experimental task). Analysis of experimental task scores of those subjects who performed satisfactorily in the pre-treatment task revealed that the knowledge based approach to database design support lead to more accurate solutions than the control system. Among the two KB approaches, Guidance approach was found to lead to better performance when compared to the Control system. It was found that the subjects perceived the Restrictive system easier to use than the Guidance system.

A Experiência como ordenação da realidade: uma estratégia orgânica para a educação científica

Knowledge is understanding. According to the philosopher Gaston Bachelard our immediate contact with the reality is only worth as confusing and provisional data. This phenomenological contact requires inventory and classification. For this reason our first reading on any phenomenon is limited to a basic levels of reality. Elements such as dynamics, functioning or detailed characteristics of what is observed can only be accessed at higher levels of reality, explains the physicist Werner Heisenberg. The ideas woven by these two great intellectuals oxygenates the notion that a well-made thinking does not require only observation and description of the nature, but assigns value and meaning to the knowledge. Based on these ideas and on the cognitive horizon brought by the complexity sciences, this research aims to nurture a reflection on our understanding of the world built from a rational perspective of experience, as an organic sequence of research. This arguments, over the study, describes how the experience is able to oxygenate a well-made thinking, as the concept created by Edgar Morin and expanded by Conceição Almeida. I argue that the experience as a path of investigative research allows one to ventures in the shadows of the unknown to access upper layers of reality. The experience is, therefore, an organic strategy for a well-made thinking - A nutritious mud that oxygenates, regulates, repairs and configures the quality of understanding. As a thread to discuss this ideas I've used my professional journey over a year and a half as a Natural Sciences' teacher on the Federal University of Rio Grande do Norte, where I could see how experiences helped on breaking a simplified understanding of the world. I chose to work with the research problems developed by 398 students over these three semesters. The problems were essential to the questioning of the phenomena that once seemed obvious or uninteresting, bringing out operational reasons and dynamics of the observed structures. Experience, in this sense, is the founder of dynamic thinking, as the need to deconstruct the phenomena's first impressions, assigning value and meaning to gestated knowledge.

Validade científica de conhecimento epidemiológico gerado com base no estudo Saúde Bucal Brasil 2003

Indicators and analyses that used the database from SB Brazil 2003 (the most recent nationwide oral health survey) have been criticized as unreliable due to sampling problems. The current study countered that this critique was based solely on statistical concepts, unsupported by empirical evidence. The critique's essentially epistemic approach leads to peremptory reductionism that denies other forms of knowledge and fails to recognize the multidisciplinary nature of epidemiology. The current study retrieves information on the implementation of the oral health survey and its impact on knowledge output in the field. The article draws an analogy between science and art, demonstrating the multifaceted images obtained by both. Thus, recognition of validity requires a full grasp of the field and appropriate use of value criteria. The current article concludes that use of the SB Brazil 2003 database is a reliable and relevant application of epidemiology to oral health.

Validade científica de conhecimento epidemiológico gerado com base no estudo Saúde Bucal Brasil 2003

Indicators and analyses that used the database from SB Brazil 2003 (the most recent nationwide oral health survey) have been criticized as unreliable due to sampling problems. The current study countered that this critique was based solely on statistical concepts, unsupported by empirical evidence. The critique's essentially epistemic approach leads to peremptory reductionism that denies other forms of knowledge and fails to recognize the multidisciplinary nature of epidemiology. The current study retrieves information on the implementation of the oral health survey and its impact on knowledge output in the field. The article draws an analogy between science and art, demonstrating the multifaceted images obtained by both. Thus, recognition of validity requires a full grasp of the field and appropriate use of value criteria. The current article concludes that use of the SB Brazil 2003 database is a reliable and relevant application of epidemiology to oral health.

Development and Testing of An Automatic Lung IMRT Planning Algorithm

Knowledge-based radiation treatment is an emerging concept in radiotherapy. It

mainly refers to the technique that can guide or automate treatment planning in

clinic by learning from prior knowledge. Dierent models are developed to realize

it, one of which is proposed by Yuan et al. at Duke for lung IMRT planning. This

model can automatically determine both beam conguration and optimization ob-

jectives with non-coplanar beams based on patient-specic anatomical information.

Although plans automatically generated by this model demonstrate equivalent or

better dosimetric quality compared to clinical approved plans, its validity and gener-

ality are limited due to the empirical assignment to a coecient called angle spread

constraint dened in the beam eciency index used for beam ranking. To eliminate

these limitations, a systematic study on this coecient is needed to acquire evidences

for its optimal value.

To achieve this purpose, eleven lung cancer patients with complex tumor shape

with non-coplanar beams adopted in clinical approved plans were retrospectively

studied in the frame of the automatic lung IMRT treatment algorithm. The primary

and boost plans used in three patients were treated as dierent cases due to the

dierent target size and shape. A total of 14 lung cases, thus, were re-planned using

the knowledge-based automatic lung IMRT planning algorithm by varying angle

spread constraint from 0 to 1 with increment of 0.2. A modied beam angle eciency

index used for navigate the beam selection was adopted. Great eorts were made to assure the quality of plans associated to every angle spread constraint as good

as possible. Important dosimetric parameters for PTV and OARs, quantitatively

re

ecting the plan quality, were extracted from the DVHs and analyzed as a function

of angle spread constraint for each case. Comparisons of these parameters between

clinical plans and model-based plans were evaluated by two-sampled Students t-tests,

and regression analysis on a composite index built on the percentage errors between

dosimetric parameters in the model-based plans and those in the clinical plans as a

function of angle spread constraint was performed.

Results show that model-based plans generally have equivalent or better quality

than clinical approved plans, qualitatively and quantitatively. All dosimetric param-

eters except those for lungs in the automatically generated plans are statistically

better or comparable to those in the clinical plans. On average, more than 15% re-

duction on conformity index and homogeneity index for PTV and V40, V60 for heart

while an 8% and 3% increase on V5, V20 for lungs, respectively, are observed. The

intra-plan comparison among model-based plans demonstrates that plan quality does

not change much with angle spread constraint larger than 0.4. Further examination

on the variation curve of the composite index as a function of angle spread constraint

shows that 0.6 is the optimal value that can result in statistically the best achievable

plans.

An Investigation into the Failure to Implement a Universal School Lunch Program during WWII and Postwar Reconstruction in Canada: The Case of Ontario

The purpose of this research is to investigate the various social, political and economic factors that contributed to Canada’s failure to implement a universal school lunch program during the 1940s. Although Canada developed several other social welfare programs in the post-war period, it remains one of the only industrialized nations that does not provide hot meals to children in elementary or secondary schools. Data from the province of Ontario, a major site of postwar reconstruction and policy-making, has been taken up to inform the broader national discourse on school lunches from the 1940s. National, Ontario provincial and City of Toronto archival records were collected and analyzed according to common themes, in order to identify key barriers that constrained government support of a hot meal program. Archival records were identified using key words, and were limited to materials created between 1930-1952. Analysis suggests that sufficient need for a hot meal program had not been established during the 1940s. Despite misleading nutrition messages, rates of malnutrition and nutrient-related disease were at an all-time low, and many Ontario school boards did not appear to have the necessary infrastructure required to supply all pupils with hot meals. The Canadian government had already employed significant resources to improve existing social security programs by coupling them with health education. This strategy reflected a shift in understanding malnutrition as a knowledge-based problem, as opposed to income-based. This understanding was further reinforced through the moralized dissemination of nutrition information, which placed blame on women for improperly raising their children. Ultimately, the strong uptake of nutrition as a public health issue in Ontario may have limited prospective responses to solutions already utilized in the public health domain, and directed favour away from a universal school lunch program for Canada.

Improving innovation and performance of Social Enterprises: Knowing what they know

Social Enterprises (SEs) are normally micro and small businesses that trade to tackle social problems, and to improve communities, people’s life chances, and the environment. Thus, their importance to society and economies is increasing. However, there is still a need for more understanding of how these organisations operate, perform, innovate and scale-up. This knowledge is crucial to design and provide accurate strategies to enhance the sector and increase its impact and coverage. Obtaining this understanding is the main driver of this paper, which follows the theoretical lens of the Knowledge-based View (KBV) theory to develop and assess empirically a novel model for knowledge management capabilities (KMCs) development that improves performance of SEs. The empirical assessment consisted of a quantitative study with 432 owners and senior members of SEs in UK, underpinned by 21 interviews. The findings demonstrate how particular organisational characteristics of SEs, the external conditions in which they operate, and informal knowledge management activities, have created overall improvements in their performance of up to 20%, based on a year-to-year comparison, including innovation and creation of social and environmental value. These findings elucidate new perspectives that can contribute not only to SEs and SE supporters, but also to other firms.

Validade científica de conhecimento epidemiológico gerado com base no estudo Saúde Bucal Brasil 2003

NARVAI, Paulo Capel et al. Validade científi ca de conhecimento epidemiológico gerado com base no estudo Saúde Bucal Brasil 2003. Caderno de saúde pública, Rio de Janeiro, v. 26, n. 4, p. 647-670, abr. 2010.

Multimodal attention system for an interactive robot

[EN]Social robots are receiving much interest in the robotics community. The most important goal for such robots lies in their interaction capabilities. An attention system is crucial, both as a filter to center the robot’s perceptual resources and as a mean of letting the observer know that the robot has intentionality. In this paper a simple but flexible and functional attentional model is described. The model, which has been implemented in an interactive robot currently under development, fuses both visual and auditive information extracted from the robot’s environment, and can incorporate knowledge-based influences on attention.

Redes Interorganizacionais: um estudo sobre partilha e utilização do conhecimento em organizações da Rede Associativa Empresarial da Região Centro de Portugal

Tese de doutoramento em Psicologia, na especialidade de Psicologia das Organizações, do Trabalho e dos Recursos Humanos

Temporal reasoning about action and change

Abstract not available

La cartographie participative dans la gestion cadastrale coutumière dans la tribu de Wan Pwec à Hienghène en Nouvelle-Calédonie

La cartographie participative est l’une des multiples disciplines de la géomatique. Elle a débuté dans les années 1980 afin d’aider les populations locales des pays du Sud à développer leur territoire. C’est en Nouvelle-Calédonie, dans la tribu de Wan Pwec que nous allons voir les intérêts, d’un tel processus de cartographie participative. Il est important de souligner que ce n’est pas pour développer son territoire que cette discipline est utilisée, mais plutôt pour montrer et démontrer les logiques traditionnelles de gestion de la terre existant dans les tribus kanak : logiques traditionnelles basées sur un savoir transmis de génération en génération de façon orale. C’est sur les terres coutumières de la tribu de Wan Pwec, que nous allons voir comment la vision mentale possédée par les chefs de familles et le chef de clan administre et gère les terres familiales. C’est dans une société kanak caractérisée par une forte tradition orale et n’ayant connu aucun support papier pour conserver et archiver ses connaissances que ce mémoire s’incorpore. À l’aide de la géomatique, d’une étude de cas sur le terrain et d’autres disciplines (comme l’anthropologie, le droit, l’histoire, la géographie, etc.), ce mémoire propose les résultats de ses travaux sur le savoir traditionnel du foncier coutumier.

Decision-making process in Portuguese Erasmus student mobility: case study

With the evolution of nowadays knowledge-based economies, the labour class becomes more competitive. As a way of getting skills that bring benefits to their careers, university students take advantage of the many opportunities available and go abroad to study. This study develops and empirically tests a structural model that examines the antecedents that influence the decision-making process of an Erasmus student under mobility for studies (EMS) in Aveiro, Coimbra and Porto (2014-2015). Reliability analysis, exploratory factor analysis and linear regressions were used to evaluate the model. Based on a survey with a sample of 872 valid responses, this study has demonstrated that EMS students are also influenced by touristic factors, which gives support to what has recently been approached by other authors. Conclusions and suggestions can be applied by other organizations, mainly Higher Education Institutions in order to attract more EMS students.