There is an increasing demand for reliable wireless communication in embedded real time systems.  Various communication requirements make the development and deployment of applications that rely on the existence of a protocol stack a challenging research and industrial field of activity. Suitable protocol stacks need to be designed and implemented on new hardware platforms and software structures. Applications that exchange packets over a wireless medium have to deal with time constraints, error checks and have to be aware of energy consumption.   PIE (Platform for Intelligent Embedded Systems) is an experimental platform developed at Halmstad University for educational purposes.  It is a robotic vehicle with wireless communication capabilities that can be used to experiment with traffic scenarios where the vehicles communicate in order to cooperate, for example to avoid hazards or to build platoons.   This thesis addresses the design and implementation of a protocol stack suitable for the PIE platform in the area of vehicle alert systems. Requirements include low latencies along with low packet loss ratios.  The thesis addresses also experimenting with reactive objects for programming network software.

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In over twenty years of operations the Canadian Innovation Centre has evaluated, through its Inventor's Assistance Program (IAP), the commercial potential of over 12,000 early stage inventions. Prior to 1989, the Canadian Innovation Centre (CIC) used a version of the Preliminary Innovation Evaluation System (PIES), developed by Gerald Udell at the Oregon Innovation Center in 1974, to evaluate the commercial potential of early stage inventions. Since 1989, the CIC has used a modified version of PIES in their evaluation process. I first estimate the ability of this program's analysts to forecast the probability that an invention will become commercialized. I also estimate a model to predict the probability that an invention will become commercialized based on the IAP's evaluation of several underlying early stage characteristics of the invention. I find that such a statistical model is based on a limited set of variables and predicts future commercial success almost as well as the IAP's forecast of success. I then use factor analysis to determine if the ratings provided by the CIC evaluation service are representative of the underlying theoretical variable structure of PIES or their modified version. Factor analysis is applied to two distinct periods that are separated by a distinct alteration of the theoretical variable structure in 1989. While I find that the factor analysis provides evidence that the post 1989 theoretical structure does provide interpretation of some of the dimensions in the ranking variables, when a combination of the post 1989 and the pre 1989 structure are examined interpretability of the extracted factors is significantly improved. Finally, I compare the model estimated on the underlying early stage characteristics with a model estimated on the extracted factors. When the predictive accuracy of the two models is compared, I find that both procedures produce models that predict almost equally well. The models and the IAP perform better than R&D managers' predictions of their own R&D projects' successes. The thesis provides recommendations for the assessment and maintenance of evaluation models for inventions, innovations and R&D projects.

In over twenty years of operations the Canadian Innovation Centre has evaluated, through its Inventor's Assistance Program (IAP), the commercial potential of over 12,000 early stage inventions. Prior to 1989, the Canadian Innovation Centre (CIC) used a version of the Preliminary Innovation Evaluation System (PIES), developed by Gerald Udell at the Oregon Innovation Center in 1974, to evaluate the commercial potential of early stage inventions. Since 1989, the CIC has used a modified version of PIES in their evaluation process. I first estimate the ability of this program's analysts to forecast the probability that an invention will become commercialized. I also estimate a model to predict the probability that an invention will become commercialized based on the IAP's evaluation of several underlying early stage characteristics of the invention. I find that such a statistical model is based on a limited set of variables and predicts future commercial success almost as well as the IAP's forecast of success. I then use factor analysis to determine if the ratings provided by the CIC evaluation service are representative of the underlying theoretical variable structure of PIES or their modified version. Factor analysis is applied to two distinct periods that are separated by a distinct alteration of the theoretical variable structure in 1989. While I find that the factor analysis provides evidence that the post 1989 theoretical structure does provide interpretation of some of the dimensions in the ranking variables, when a combination of the post 1989 and the pre 1989 structure are examined interpretability of the extracted factors is significantly improved. Finally, I compare the model estimated on the underlying early stage characteristics with a model estimated on the extracted factors. When the predictive accuracy of the two models is compared, I find that both procedures produce models that predict almost equally well. The models and the IAP perform better than R&D managers' predictions of their own R&D projects' successes. The thesis provides recommendations for the assessment and maintenance of evaluation models for inventions, innovations and R&D projects.

Texte remanié de: Tesis doctoral--Facultat de ciències de l'educació--Universitat de Barcelona, 1994. / Choix de documents en appendice. Bibliogr. p. 419-434. Index.

Subtropical mode water is a voluminous body of water in the ocean whose main feature is the homogeneity in both vertical structure and horizontal extension. The subtropical mode water (STMW) of the southwest Atlantic is formed between the months of July and October near the Brazil-Malvinas confluence and along the Brazil Current recirculation gyre. The formation region extends on the order of 3000 km zonally, from 20°W to 50°W, and 1000 km meridionally, from 30°S to 40°S, and it is typically about 170 m thick. In situ data from pressure-equipped inverted echo sounders (PIES) installed in the western portion of the basin, along 34.5°S, are available from 2009 to the present. These data after processed and calibrated can provide an unprecedented description of the STMW involving processes since its formation at the surface until the final stage of its residence in the interior of the ocean. Temperature and salinity data estimated by the PIES are based on empirical look-up tables that relate the acoustic travel time with the baroclinic structure of the ocean. This technique is known as the Gravest Empirical Mode (GEM), and here it is used to detect profiles containing homogeneous segments of temperature and salinity that characterize the mode water. The GEM method was seasonally corrected to reconstruct surface variability necessary for STMW formation. The interannual covariance between STMW layer thickness and the Brazil Current was calculated, but no significant correlation at that time scale was observed. The mode water layer detected was about 220 m ± 55 m thick on all sites, agreeing with previous studies. / A água modal subtropical é um grande volume de água no oceano cuja característica principal é a homogeneidade nas estruturas vertical e horizontal. A água modal subtropical do sudoeste do Atlântico é formada entre os meses de julho e outubro perto da confluência Brasil-Malvinas e ao longo da recirculação da Corrente do Brasil. A região de formação se estende na ordem de 3000 km zonalmente, de 20°W a 50°W e 1000 km meridionalmente, de 30°S a 40°S, e tipicamente tem cerca de 170 m de espessura. Dados in situ de ecossondas invertidas com sensor de pressão (PIES) instaladas na porção ocidental da bacia, ao longo de 34,5°S, estão disponíveis a partir de 2009 até o presente. Estes dados após o processamento e calibração podem fornecer uma descrição sem precedentes da Água Modal Subtropical do Atlântico Sul envolvendo processos desde sua formação na superfície até o estágio final de sua permanência no interior do oceano. Os dados de temperatura e salinidade estimados pelos PIES são baseados em tabelas de referência (look-up tables) que relacionam o tempo de retorno do sinal acústico com a estrutura baroclínica do oceano. Esta técnica é conhecida como o Gravest Empirical Mode (GEM),e aqui é usado para detectar perfis contendo segmentos homogêneos de temperatura e salinidade que caracterizam a água modal. Foi aplicada uma correção sazonal ao método GEM para reconstruir a variabilidade da superfície necessária para a formação STMW. A covariância interanual entre a espessura da camada STMW e a corrente do Brasil foi calculada, mas não foi observada correlação significativa naquela escala de tempo. A camada de água em modo detectada foi de cerca de 220 m ± 55 m de espessura em todos os sites, concordando com estudos prévios.

Subtropical mode water is a voluminous body of water in the ocean whose main feature is the homogeneity in both vertical structure and horizontal extension. The subtropical mode water (STMW) of the southwest Atlantic is formed between the months of July and October near the Brazil-Malvinas confluence and along the Brazil Current recirculation gyre. The formation region extends on the order of 3000 km zonally, from 20°W to 50°W, and 1000 km meridionally, from 30°S to 40°S, and it is typically about 170 m thick. In situ data from pressure-equipped inverted echo sounders (PIES) installed in the western portion of the basin, along 34.5°S, are available from 2009 to the present. These data after processed and calibrated can provide an unprecedented description of the STMW involving processes since its formation at the surface until the final stage of its residence in the interior of the ocean. Temperature and salinity data estimated by the PIES are based on empirical look-up tables that relate the acoustic travel time with the baroclinic structure of the ocean. This technique is known as the Gravest Empirical Mode (GEM), and here it is used to detect profiles containing homogeneous segments of temperature and salinity that characterize the mode water. The GEM method was seasonally corrected to reconstruct surface variability necessary for STMW formation. The interannual covariance between STMW layer thickness and the Brazil Current was calculated, but no significant correlation at that time scale was observed. The mode water layer detected was about 220 m ± 55 m thick on all sites, agreeing with previous studies. / A água modal subtropical é um grande volume de água no oceano cuja característica principal é a homogeneidade nas estruturas vertical e horizontal. A água modal subtropical do sudoeste do Atlântico é formada entre os meses de julho e outubro perto da confluência Brasil-Malvinas e ao longo da recirculação da Corrente do Brasil. A região de formação se estende na ordem de 3000 km zonalmente, de 20°W a 50°W e 1000 km meridionalmente, de 30°S a 40°S, e tipicamente tem cerca de 170 m de espessura. Dados in situ de ecossondas invertidas com sensor de pressão (PIES) instaladas na porção ocidental da bacia, ao longo de 34,5°S, estão disponíveis a partir de 2009 até o presente. Estes dados após o processamento e calibração podem fornecer uma descrição sem precedentes da Água Modal Subtropical do Atlântico Sul envolvendo processos desde sua formação na superfície até o estágio final de sua permanência no interior do oceano. Os dados de temperatura e salinidade estimados pelos PIES são baseados em tabelas de referência (look-up tables) que relacionam o tempo de retorno do sinal acústico com a estrutura baroclínica do oceano. Esta técnica é conhecida como o Gravest Empirical Mode (GEM),e aqui é usado para detectar perfis contendo segmentos homogêneos de temperatura e salinidade que caracterizam a água modal. Foi aplicada uma correção sazonal ao método GEM para reconstruir a variabilidade da superfície necessária para a formação STMW. A covariância interanual entre a espessura da camada STMW e a corrente do Brasil foi calculada, mas não foi observada correlação significativa naquela escala de tempo. A camada de água em modo detectada foi de cerca de 220 m ± 55 m de espessura em todos os sites, concordando com estudos prévios.