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31.
This paper examines the formation of heating practices at the time of moving house. Interviews on occupant changes in Finnish single-family houses with a focus on heating arrangements and thermal comfort reveal that practice formation in and around occupant changes is a complex process of aligning elements where the house stands out as a coordinative and coordinated aggregate. As houses pass from one set of occupants to the next, they carry practices and delineate new ways of operation to the new occupants. The study demonstrates the temporal unfolding of the hidden complexity to what seems like a straightforward process of residents interacting with a new heating system and home. The findings contribute to the understanding of the domestic sphere as a space for practice formation. 相似文献
32.
Peetu Nieminen Salvador Esque Ali Muhammad Jouni Mattila Jukka Vyrynen Mikko Siuko Matti Vilenius 《Fusion Engineering and Design》2009,84(7-11):1420-1424
Department of Intelligent Hydraulics and Automation (IHA) of Tampere University of Technology has been involved in the European Fusion program since 1994 within the ITER reactor maintenance activities. In this paper we discuss the design and development of a six degrees of freedom water hydraulic manipulator with a force feedback for teleoperation tasks. The manipulator is planned to be delivered to Divertor Test Platform 2 (DTP2) during year 2008. The paper also discusses the possibility to improve the fail safe and redundant operation of the manipulator. During the design of the water hydraulic manipulator, special provisions have been made in order to meet the safety requirements such as servo valve block for redundant operation and safety vane brakes for fail safe operation. 相似文献
33.
Johan Plomp Mikko Heiskanen Mika Hillukkala Tapio Heikkilä Jari Rehu Niek Lambert Victor van Acht Tom Ahola 《International Journal of Wireless Information Networks》2011,18(4):280-294
In this paper, we highlight considerations for synchronization issues in body area networks. Requirements for the synchronization
accuracy in body area networks depend on the application at hand. Synchronization may be needed for power management, sample
ordering, calculation of stimulus responses and for sensor fusion. This paper provides a theoretical exercise to help understand
the accuracy required for typical human motion sensing. It gives an overview of various synchronisation strategies used and
implemented in prototype systems. Lessons learnt from practical implementations using Bluetooth, an IEEE 802.15.4 proprietary
network and Nanonet are presented to illustrate the principles involved. The discussion provides some considerations and the
requirements for typical WBAN applications. 相似文献
34.
Mikko SavolainenMikko Huhtanen Antti HäkkinenBjarne Ekberg Rolf HindströmJuha Kallas 《Minerals Engineering》2011,24(8):876-885
Small-scale laboratory tests for sizing and designing disc filters are typically performed by using leaf test equipment. Although the basic tests are fairly simple and quick, the accuracy and repeatability of the results may be poor due to various reasons. In addition to errors caused by variations in the structure of the equipment, also the skills and experience of the person performing the tests is of great importance. This paper introduces an experimental study carried out for defining the most important sources of errors in these kinds of laboratory tests and for estimating their influence on the final test results. The results obtained in this study were utilized for designing an improved version of the test equipment and also for creating a standard procedure for performing the tests. The results acquired with the small-scale laboratory tests were in good agreement with the performance results obtained from full-scale ceramic disc filters operating in industrial processes. 相似文献
35.
Heikki Käsnänen Mikko J. Myllymäki Anna Minkkilä Antti O. Kataja Susanna M. Saario Dr. Tapio Nevalainen Dr. Ari M. P. Koskinen Prof. Dr. Antti Poso Prof. Dr. 《ChemMedChem》2010,5(2):213-231
Carbamates are a well‐established class of fatty acid amide hydrolase (FAAH) inhibitors. Here we describe the synthesis of meta‐substituted phenolic N‐alkyl/aryl carbamates and their in vitro FAAH inhibitory activities. The most potent compound, 3‐(oxazol‐2yl)phenyl cyclohexylcarbamate ( 2 a ), inhibited FAAH with a sub‐nanomolar IC50 value (IC50=0.74 nM ). Additionally, we developed and validated three‐dimensional quantitative structure–activity relationships (QSAR) models of FAAH inhibition combining the newly disclosed carbamates with our previously published inhibitors to give a total set of 99 compounds. Prior to 3D‐QSAR modeling, the degree of correlation between FAAH inhibition and in silico reactivity was also established. Both 3D‐QSAR methods used, CoMSIA and GRID/GOLPE, produced statistically significant models with coefficient of correlation for external prediction (R2PRED) values of 0.732 and 0.760, respectively. These models could be of high value in further FAAH inhibitor design. 相似文献
36.
Friction is widely used as an indicator of surface slipperiness in preventing accidents in slips and falls. Surface texture affects friction, but it is not clear which surface characteristics are better correlated with friction. Highly correlated surface characteristics could be used as potential interventions to prevent slip and fall accidents. The dynamic friction between quarry tiles and a commonly used sole testing material, Neolite, using three different mixtures of glycerol and water as contaminants at the interface was correlated with the surface parameters of the tile surfaces. The surface texture was quantified with various surface roughness and surface waviness parameters using three different cut-off lengths to filter the measured profiles for obtaining the profiles of either surface roughness or surface waviness. The correlation coefficients between the surface parameters and the measured friction were affected by the glycerol contents and cut-off lengths. Surface waviness parameters could potentially be better indicators of friction than commonly used surface roughness parameters, especially when they were measured with commonly used cut-off lengths or when the viscosity of the liquid contaminant was high. 相似文献
37.
Mikko Waltari Lauri Sumanen Tuomas Korhonen Kari A. I. Halonen 《Analog Integrated Circuits and Signal Processing》2003,37(3):201-213
A 13-bit, 50-MS/s pipeline ADC with IF-sampling capability is presented. A high sampling linearity is obtained through the use of bootstrapped switches. A digital self-calibration algorithm with modified capacitor measurement scheme is employed to improve the accuracy of the first two pipeline stages. The prototype, implemented with a 0.35-m BiCMOS (SiGe) technology, shows a 76.5-dB SFDR at a 194.2-MHz signal frequency and dissipates 715 mW power from a 2.9-V supply. 相似文献
38.
Andrew?J.?MayEmail author Tracy?Ross Steven?H.?Bayer Mikko?J.?Tarkiainen 《Personal and Ubiquitous Computing》2003,7(6):331-338
Recent years have seen an increased interest in navigational services for pedestrians. To ensure that these services are successful, it is necessary to understand the information requirements of pedestrians when navigating, and in particular, what information they need and how it is used. A requirements study was undertaken to identify these information requirements within an urban navigation context. Results show that landmarks were by far the most predominant navigation cue, that distance information and street names were infrequently used, and that information is used to enable navigation decisions, but also to enhance the pedestrians confidence and trust. The implications for the design of pedestrian navigation aids are highlighted. 相似文献
39.
The validity and reliability of a portable slip meter for determining floor slipperiness during simulated heel strike 总被引:2,自引:0,他引:2
A previously developed test rig was used as starting point for designing a portable slip meter with two new features. First, an inflatable pneumatic test wheel, consisting of six slider units, was introduced as the impacting contact element relative to floor surface. Second, an inductive trigger was built into the system to facilitate a precise timing of the slider-floor contact during the test. This new test rig was designed to measure transitional friction properties of contaminated floor surfaces during simulated heel strike, which is considered the most critical phase of gait from the slip and fall point of view. Another objective was to quantify the validity and reliability of this test method in the laboratory, but not yet in the field. The measurement process was evaluated on eight wet and oily floor surfaces (vinyl and ceramic tile floorings) using two slider materials (plain, profiled), two normal loads (100, 200 N), and two sliding velocities (0.15, 0.30 m/s) as independent variables. The outputs of the portable slip meter, in terms of transitional friction coefficients, were compared to force platform-based friction values and to slip resistance values obtained with a slip simulator apparatus for laboratory testing of shoes and floor surfaces. The outputs were also evaluated against slipperiness ratings made by three male subjects in paired comparison trials, in which the subjects walked over eight wet floor surfaces wearing shoes with the plain soling material. The results showed that test option 200 N and 0.15m/s led to optimum validity despite its tendency to promote frictional vibrations (stick-slip) in the contact surface. Compared to the lower sliding speed, the higher speed reduced both stick-slip and measurement bias. Test option 200 N and 0.30 m/s was the most reliable one in this experiment. It yielded lower friction coefficients than any other test option and reduced the likelihood of underestimating slip and fall hazards. The results implied that the minimum friction coefficient was 0.25 for preventing a fall on wet floor surfaces, whereas the limit for preventing a slip was in the range 0.30-0.35. Transitional friction measurement was found to be a valid and reliable indicator for slip resistance. A more accurate control of the normal force during testing is needed for actual field use of the test method. 相似文献
40.
In this paper, we propose an architecture for secure push services for mobile users that supports common-of-the-shelf (COTS) WLAN base stations. The architecture focuses on the creation of flexible access networks based on easily deployable base stations. The push functionality is realized using client-initiated connections with SIP, and TLS or dTLS for security. The central building block of the distributed system is the edge proxy, which manages and implicitly authenticates all inbound connections, and performs privacy enhancement. The main driving force of our architecture has been airline services, but the system is applicable also for other service domains. 相似文献