797 resultados para Albedo measurement
Resumo:
Previous assessment of verticality by means of rod and rod and frame tests indicated that human subjects can be more (field dependent) or less (field independent) influenced by a frame placed around a tilted rod. In the present study we propose a new approach to these tests. The judgment of visual verticality (rod test) was evaluated in 50 young subjects (28 males, ranging in age from 20 to 27 years) by randomly projecting a luminous rod tilted between -18 and +18° (negative values indicating left tilts) onto a tangent screen. In the rod and frame test the rod was displayed within a luminous fixed frame tilted at +18 or -18°. Subjects were instructed to verbally indicate the rod’s inclination direction (forced choice). Visual dependency was estimated by means of a Visual Index calculated from rod and rod and frame test values. Based on this index, volunteers were classified as field dependent, intermediate and field independent. A fourth category was created within the field-independent subjects for whom the amount of correct guesses in the rod and frame test exceeded that of the rod test, thus indicating improved performance when a surrounding frame was present. In conclusion, the combined use of subjective visual vertical and the rod and frame test provides a specific and reliable form of evaluation of verticality in healthy subjects and might be of use to probe changes in brain function after central or peripheral lesions.
Resumo:
Although 17β-estradiol (E2) deficiency has been linked to the development of osteoarthritis (OA) in middle-aged women, there are few studies relating other estrogens and estrogen metabolites (EMs) to this condition. We developed a high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS) method to measure the levels of six EMs (i.e., estrone, E2, estriol, 2-hydroxyestrone, 2-hydroxyestradiol, and 16a-hydroxyestrone) in healthy pre- and postmenopausal women and women with OA. This method had a precision ranging from 1.1 to 3.1% and a detection limit ranging from 10 to 15 pg. Compared to healthy women, serum-free E2 was lower in the luteal and postmenopausal phases in women with OA, and total serum E2 was lower in postmenopausal women with OA. Moreover, compared to healthy women, total serum 2-hydroxyestradiol was higher in postmenopausal women with OA and total serum 2-hydroxyestrone was lower in both the luteal and follicular phases in women with OA. In conclusion, our HPLC-ESI-MS/MS method allowed the measurement of multiple biochemical targets in a single assay, and, given its increased cost-effectiveness, simplicity, and speed relative to previous methods, this method is suitable for clinical studies.
Resumo:
In this thesis the basic structure and operational principals of single- and multi-junction solar cells are considered and discussed. Main properties and characteristics of solar cells are briefly described. Modified equipment for measuring the quantum efficiency for multi-junction solar cell is presented. Results of experimental research single- and multi-junction solar cells are described.
Resumo:
The power is still today an issue in wearable computing applications. The aim of the present paper is to raise awareness of the power consumption of wearable computing devices in specific scenarios to be able in the future to design energy efficient wireless sensors for context recognition in wearable computing applications. The approach is based on a hardware study. The objective of this paper is to analyze and compare the total power consumption of three representative wearable computing devices in realistic scenarios such as Display, Speaker, Camera and microphone, Transfer by Wi-Fi, Monitoring outdoor physical activity and Pedometer. A scenario based energy model is also developed. The Samsung Galaxy Nexus I9250 smartphone, the Vuzix M100 Smart Glasses and the SimValley Smartwatch AW-420.RX are the three devices representative of their form factors. The power consumption is measured using PowerTutor, an android energy profiler application with logging option and using unknown parameters so it is adjusted with the USB meter. The result shows that the screen size is the main parameter influencing the power consumption. The power consumption for an identical scenario varies depending on the wearable devices meaning that others components, parameters or processes might impact on the power consumption and further study is needed to explain these variations. This paper also shows that different inputs (touchscreen is more efficient than buttons controls) and outputs (speaker sensor is more efficient than display sensor) impact the energy consumption in different way. This paper gives recommendations to reduce the energy consumption in healthcare wearable computing application using the energy model.
Resumo:
The value that the customer perceives from a supplier’s offering, impacts customer’s decision making and willingness to pay at the time of the purchase, and the overall satisfaction. Thus, for a business supplier, it is critical to understand their customers’ value perceptions. The objective of this thesis is to understand what measurement and monitoring system customers value, by examining their key purchasing criteria and perceived benefits. Theoretical part of this study consists on reviewing relevant literature on organizational buying behavior and customer perceived value. This study employs a qualitative interview research method. The empirical part of this research consisted of conducting 20 in-depth interviews with life science customers in USA and in Europe. Quality and technical features are the most important purchasing criteria, while product-related benefits seem to be the most important perceived benefits. At the marketing of the system, the emphasis should be at which regulations the system complies with, references of supplier’s prior experience, the reliability and usability of the system, and total costs. The benefits that should be emphasized are the better control of customer’s process, and the proof of customer’s product quality
Resumo:
In recent years, technological advancements in microelectronics and sensor technologies have revolutionized the field of electrical engineering. New manufacturing techniques have enabled a higher level of integration that has combined sensors and electronics into compact and inexpensive systems. Previously, the challenge in measurements was to understand the operation of the electronics and sensors, but this has now changed. Nowadays, the challenge in measurement instrumentation lies in mastering the whole system, not just the electronics. To address this issue, this doctoral dissertation studies whether it would be beneficial to consider a measurement system as a whole from the physical phenomena to the digital recording device, where each piece of the measurement system affects the system performance, rather than as a system consisting of small independent parts such as a sensor or an amplifier that could be designed separately. The objective of this doctoral dissertation is to describe in depth the development of the measurement system taking into account the challenges caused by the electrical and mechanical requirements and the measurement environment. The work is done as an empirical case study in two example applications that are both intended for scientific studies. The cases are a light sensitive biological sensor used in imaging and a gas electron multiplier detector for particle physics. The study showed that in these two cases there were a number of different parts of the measurement system that interacted with each other. Without considering these interactions, the reliability of the measurement may be compromised, which may lead to wrong conclusions about the measurement. For this reason it is beneficial to conceptualize the measurement system as a whole from the physical phenomena to the digital recording device where each piece of the measurement system affects the system performance. The results work as examples of how a measurement system can be successfully constructed to support a study of sensors and electronics.
Resumo:
The main goal of this master’s thesis was to find out, how to improve customer experience management and measurement. This study is a qualitative case study, in which the data collection method has been interviews. In addition, some of the company’s customer experience measurement methods have been analyzed. The theoretical background is applied in practice by interviewing 5 representatives from the case company. In the case company, the management has launched a customer experience focused program, and given guidelines for customer experience improvement. In the case company, customer experience is measured with different methods, one example is asking the recommendation readiness from a customer. In order to improve the customer experience management, the case company should define, what the company means with customer experience and what kind of customer experience the company is aiming to create. After the encounter, the customer should be left with feelings of satisfaction, positivity and trust. The company should focus on easiness in its processes, on top of which the processes should work fluently. The customer experience management should be improved through systematic planning, and by combining and standardizing different measures. In addition, some channel-based measures should be used. The measurement conducted should be more customer focused, and the case company should form an understanding, which touch points are the most relevant to measure.
Resumo:
As fibras alimentares são consumidas naturalmente em cereais, frutas e hortaliças, mas também são adicionadas na forma concentrada em alimentos processados. Diferentes fontes de fibras têm diferentes estruturas e composições químicas, que irão definir a sua finalidade nutricional ou tecnológica. Este trabalho tem como objetivo a caracterização de fibra alimentar do albedo da laranja submetida a dois métodos de secagem (liofilização e convencional) e divididas por intervalos granulométricos. Para as determinações de densidade, área superficial, porosidade e distribuição de tamanho de poro, utilizaram-se técnicas clássicas da tecnologia de sistema particulado e foram comparadas com imagens de microscopia eletrônica de varredura. Os resultados apontaram que o método de secagem é o que mais influenciou na redução do volume de poros do material, também visualizado nas características microestruturais reveladas pela análise de imagem. O intervalo granulométrico da fibra particulada apresentou-se inversamente proporcional à densidade e à área superficial específica do material. A fibra alimentar do albedo da laranja apresentou características estruturais que permitem a diversificação de novos produtos alimentícios com alto valor nutritivo e comercial.
Resumo:
O Brasil gera toneladas de resíduos de cascas e sementes de maracujá amarelo que podem ser aproveitados na alimentação humana. Os objetivos deste trabalho foram determinar os efeitos dos parâmetros do processo (volume do suco de maracujá empregado e tempo de cozimento dos albedos) sobre as propriedades físico-químicas (pH, sólidos solúveis, acidez titulável e açúcares totais) de doces em calda elaborados com a casca do maracujá, bem como sua aceitação sensorial pelos consumidores, visando o reaproveitamento dos resíduos gerados na indústria de alimentos. Utilizou-se um planejamento fatorial 2² completo para avaliação dos parâmetros e respostas. Avaliou-se a aceitação sensorial dos doces, utilizando-se escala hedônica de 9 pontos, e intenção de compra, usando-se escala de 5 pontos. Valores mais baixos de pH foram alcançados em volumes de suco e tempo de cozimento mais altos, tanto para o albedo como para a calda do doce. Maiores valores de sólidos solúveis no albedo foram encontrados em tempos de cozimento altos e em menores volumes de suco empregado. Resultados globais indicaram como condições adequadas, ao processamento do albedo de maracujá em calda, tempo de cozimento superior a 10 minutos e concentração mais elevada de suco de maracujá.
Resumo:
The objective of this research was to evaluate the effect of the citric acid concentration, pulp/sugar ratio, and albedo concentration of the passion fruit peel on physical, physiochemical, and sensorial characteristics of the 'Silver' banana preserves. A 2³ factorial design and 3 repetitions in the central point were used. The albedo concentration between 0 and 3% had significant influence on the reduction of the reducing sugars and on the decrease in titratable acidity. The increase in the pulp/sugar ratio exerted a negative effect on the pH and positive on the titratable acidity; the acid addition reduced the non-reducing sugar level. The sensorial evaluation and purchase intention indicated that the incorporation of a maximum of 1.5% albedo in formulations containing 50% pulp and 0.5% citric acid resulted in products with good acceptability in comparison with the formulation in which 60% pulp and an absence of acid or albedo is utilized.