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11.
Sami Ronkainen Emilia Koskinen Ying Liu Panu Korhonen 《Human-Computer Interaction》2013,28(2):148-193
In this article, we present a practical approach to analyzing mobile usage environments. We propose a framework for analyzing the restrictions that characteristics of different environments pose on the user's capabilities. These restrictions along with current user interfaces form the cost of interaction in a certain environment. Our framework aims to illustrate that cost and what causes it. The framework presents a way to map features of the environment to the effects they cause on the resources of the user and in some cases on the mobile device. This information can be used for guiding the design of adaptive and/or multimodal user interfaces or devices optimized for certain usage environments. An example of using the framework is presented along with some major findings and three examples of applying them in user interface design. 相似文献
12.
Estimation of tree crown volume from airborne lidar data using computational geometry 总被引:1,自引:0,他引:1
Lauri Korhonen Jari Vauhkonen Anni Virolainen Aarne Hovi Ilkka Korpela 《International journal of remote sensing》2013,34(20):7236-7248
Although simple geometrical shapes are commonly used to describe tree crowns, computational geometry enables calculation of the individual crown properties directly from airborne lidar point clouds. Our objective was to calculate crown volumes (CVs) using this technique and validate the results by comparing them with field-measured values and modelled ellipsoidal crowns. The CVs of standing trees were obtained by measuring the crown radii at different heights, integrating the obtained crown profiles as solids of revolution, and finally averaging the volumes obtained from the four separate profiles. With the lidar data, the CVs were extracted using 3D alpha shape and 3D convex hull techniques. Crown base heights (CBHs) were also estimated from the lidar data and used to exclude echoes from the understory, which was also done using field-based CBHs to exclude this error source. The results show that the field-measured CVs had a high correlation with lidar-based estimates (best R 2 = 0.83), but the lidar-based estimates were generally smaller than the field values. The best correspondence (root mean square difference (RMSD) = 45.0%, average difference = –24.7%) was obtained using the convex hull of the point data and field-measured CBH. The CBHs were consistently overestimated (RMSD = 37.3%; average difference = –20.0%), especially in spruces with long crowns. Thus using lidar-based CBH also increased the inaccuracy of the CV estimates. While the underestimation of CV is mainly explained by the inadequate number of echoes from the lower regions of the crowns, the CVs obtained from the lidar were better than those obtained with ellipsoids fitted by using general models for crown dimensions. The utility of the estimated CVs in the prediction of stem diameter is also demonstrated. 相似文献
13.
M. Vidgren M. Silvasti P. Vidgren H. Sormunen K. Laurikainen P. Korhonen 《Aerosol science and technology》2013,47(4):335-345
Due to the depletion of ozone layer linked to CFf propellants used in metered-dose inhalers (MDIs), alternative drug delivery systems for inhalation therapy of bronchial asthma is required. Dry powder inhalers have become a remarkable alternative to the MDIs. The research of powder delivery systems has strongly been focused on developing portable, preloaded multiple-dose powder inhalers, from which patients can reliably inhale several drug doses. Recently, a novel multiple-dose powder inhaler (Easyhaler®) has been developed. Easyhaler® is a suitable drug delivery system for various drugs already available or still under development. Optimum patient compliance is achieved by a design similar to the dose delivery system of the conventional MDI. In addition, the construction of the device allows high dose reproducibility and good in vitro and in vivo deposition of inhaled drug particles. Consequently, equal therapeutic efficacy, safety and tolerability with an MDI is documented in clinical trials. Thus the pharmaceutical, biopharmaceutical, and clinical features as well as the similar mode of use would facilitate a smooth transition from the freon based MDIs to the Easyhaler® multiple-dose powder inhaler. 相似文献
14.
Studied head movements to a tone to the left ear (conditioned stimulus [CS]) in 6 cats. An attempt was made to differentiate an orienting, short-latency (alpha) response from the long-latency conditioned (delayed) response. The unconditioned stimulus (UCS) was a brain stimulation to the lateral hypothalamus eliciting a specific, stereotypical head movement. These behavioral characteristics of the unconditioned head movement were used for differentiating it from the conditioned short-latency head movement. Paired conditioning and randomly unpaired control sessions (5 daily sessions each) were given in balanced order to each S. Evoked neural responses in the hippocampus and cingulate cortex were recorded simultaneously to compare the time–amplitude characteristics of evoked responses to earlier findings in multiple-unit recordings. The results supported the differentiation of the behavioral responses. The time–amplitude course of the evoked neural responses showed complex changes, appearing as an increase in the negativity during the alpha-response period and as an increase in the positivity during the long-latency period on omitted-UCS (CS-alone test) trials. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
15.
Intake of fatty acids and risk of coronary heart disease in a cohort of Finnish men. The Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study 总被引:3,自引:0,他引:3
P Pietinen A Ascherio P Korhonen AM Hartman WC Willett D Albanes J Virtamo 《Canadian Metallurgical Quarterly》1997,145(10):876-887
The relation of intakes of specific fatty acids and the risk of coronary heart disease was examined in a cohort of 21,930 smoking men aged 50-69 years who were initially free of diagnosed cardiovascular disease. All men participated in the Finnish Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study and completed a detailed and validated dietary questionnaire at baseline. After 6.1 years of follow-up from 1985-1988, the authors documented 1,399 major coronary events and 635 coronary deaths. After controlling for age, supplement group, several coronary risk factors, total energy, and fiber intake, the authors observed a significant positive association between the intake of trans-fatty acids and the risk of coronary death. For men in the top quintile of trans-fatty acid intake (median = 6.2 g/day), the multivariate relative risk of coronary death was 1.39 (95% confidence interval (CI) 1.09-1.78) (p for trend = 0.004) as compared with men in the lowest quintile of intake (median = 1.3 g/day). The intake of omega-3 fatty acids from fish was also directly related to the risk of coronary death in the multivariate model adjusting also for trans-saturated and cis-monounsaturated fatty acids (relative risk (RR) = 1.30, 95% CI 1.01-1.67) (p for trend = 0.06 for men in the highest quintile of intake compared with the lowest). There was no association between intakes of saturated or cis-monounsaturated fatty acids, linoleic or linolenic acid, or dietary cholesterol and the risk of coronary deaths. All the associations were similar but somewhat weaker for all major coronary events. 相似文献
16.
Five Finnish ruminally cannulated Ayrshire cows were used in a 5 x 5 Latin square trial with 14-d periods to determine whether branched-chain amino acids (AA) are the second- or colimiting AA for milk protein synthesis on grass silage-cereal based diet. Mammary metabolism of AA as well as AA supply from the basal diet were also studied. Grass silage (17.5% crude protein) was given ad libitum with 9 kg/d as a cereal-based concentrate (13.8% crude protein). Treatments were basal diet without AA infusion (Control), abomasal infusion of AA mixture of His, Ile, Leu, and Val at 8.5, 14.9,27.9, and 18.3 g/d, respectively, AA mixture minus Ile, AA mixture minus Leu, and AA mixture minus Val. Glucose was infused on all treatments at 250 g/d. Amino acid infusions had no effect on dry matter intake (mean 19.2 kg/d), yields of milk (mean 25.3 kg/d), energy-corrected milk (mean 25.9 kg/d), milk protein (mean 807 g/d), lactose (mean 1261 g/d), or fat (mean 1056 g/d). Milk composition was not affected by the treatments. Plasma concentrations of His and Val responded to AA infusions but concentration of Ile increased only on treatment AA mixture minus Leu, and concentration of Leu only on treatment AA mixture minus Ile. Infusion of AA mixture of His, Ile, Leu, and Val decreased plasma concentrations of Arg, Lys, Met, Phe, and Tyr. Amino acid infusions did not affect concentrations of plasma urea and energy metabolites or AA utilization by the mammary gland. Based on unchanged production parameters, the supply of His or branched-chain AA seemed not to be limiting under the current dietary conditions. Changes in plasma AA concentrations suggest either antagonism between individual AA in absorption or increased partitioning of AA into the muscle tissues. About 75% of omasal canal nonammonia nitrogen flow (427 g/d) was of microbial origin, and AA profiles of microbial protein and omasal canal digesta were fairly similar. Postruminal AA supply seems to be dependent on the basal diet, but variation may exist even within the similar basal diets. 相似文献
17.
Reliability assessment of chip level interconnects is based on accelerated testing at a higher temperature and a larger current density than expected in service conditions. The critical parameters needed to extrapolate accelerated test data to service conditions are the activation energy, Q, and the current density exponent, n. Although current density exponents and activation energies are well known for the elemental processes (like void nucleation due to electromigration (EM) generated stress), there is no consensus on which apparent activation energy or current density exponent values would be applicable in reliability estimates for realistic line structures. Here, we first review our EM simulation tool. We then apply the EM simulation tool to statistical life time analysis of realistic-like line structures generated by a Monte-Carlo algorithm. For a given grain structure distribution, the stress evolution along the line is simulated, letting voids nucleate at the sites where the stress exceeds a critical level, and the nucleated voids are then allowed to grow till the largest one reaches the preset critical size, resulting in a ‘failure’ of the particular line. By repeating this process for various current densities and temperatures, it becomes possible to extract the apparent activation energies and current density exponents from the simulation data. 相似文献
18.
Sami Myllymaa Emilia Kaivosoja Katja Myllymaa Tarvo Sillat Hannu Korhonen Reijo Lappalainen Yrj? T. Konttinen 《Journal of materials science. Materials in medicine》2010,21(1):329-341
It was hypothesized that human mesenchymal stromal cell (hMSC) can be guided by patterned and plain amorphous diamond (AD),
titanium (Ti), tantalum (Ta) and chromium (Cr) coatings, produced on silicon wafer using physical vapour deposition and photolithography.
At 7.5 h hMSCs density was 3.0–3.5× higher (P < 0.0003, except Ti) and cells were smaller (68 vs. 102 μm, P 0.000006–0.02) on patterns than on silicon background. HMSC-covered surface of the background silicon was lower on Ti than
AD patterns (P = 0.015), but at 5 days this had reversed (P = 0.006). At 7.5 h focal vinculin adhesions and actin cytoskeleton were outgoing from pattern edges so cells assumed geometric
square shapes. Patterns allowed induced osteogenesis, but less effectively than plain surfaces, except for AD, which could
be used to avoid osseointegration. All these biomaterial patterns exert direct early, intermediate and late guidance on hMSCs
and osteogenic differentiation, but indirect interactions exist with cells on silicon background. 相似文献
19.
Quit and Win campaigns as a long-term anti-smoking intervention in North Karelia and other parts of Finland 总被引:1,自引:0,他引:1
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T. Korhonen E. Urjanheimo P. Mannonen H. Korhonen A. Uutela P. Puska 《Tobacco control》1999,8(2):175-181
OBJECTIVE: To evaluate Quit and Win campaigns repeated in North Karelia and rest of Finland. DESIGN: Repeated comparisons of participation rates, abstinence rates, and other measures between North Karelia and the rest of Finland. SUBJECTS: Adult daily smokers in Finland participating in the Quit and Win contests in 1986-1997. INTERVENTIONS: Quit and Win smoking cessation campaigns targeted at adult daily smokers throughout Finland in 1986, 1989, 1994, 1996, and 1997, including more intensive activities in North Karelia. MAIN OUTCOME MEASURES: Participation rates, self reported six-month abstinence rates, other effectiveness measures (% of smokers who attended, intended, tried, and succeeded in cessation). RESULTS: North Karelia's participation rates were significantly higher in each campaign compared with the rest of Finland. The abstinence rates in North Karelia were also higher, the difference being significant in 1986 and 1994 (p < 0.05). In the target population in 1996 over 75% of smokers in North Karelia, compared with 40% of smokers surveyed elsewhere, reported awareness of the campaign (p < 0.001). Approximately 9% of the smokers in North Karelia and 6% elsewhere intended to participate (p = NS). Over 2% in North Karelia, compared with less than 1% elsewhere, tried to quit (p < 0.001). Among the targeted group, 0.3% of North Karelian smokers were complete abstainers throughout the 12 months of follow up, compared with an average of 0.1% in other areas (p < 0.001). CONCLUSIONS: The Quit and Win campaign is a feasible cessation method in long-term community-wide programmes. Intensified community activities are associated with higher success. In repeat campaigns, high participation and abstinence rates can be maintained. 相似文献
20.
A. S. Korhonen 《Journal of Materials Engineering and Performance》2013,22(2):505-511
The aim of this study is to investigate the work-hardening of AA 3104-H19 aluminum alloy. Uniaxial tensile tests were carried out in both the rolling and transverse directions. In the past, some authors have used such uniaxial tensile test data and the Hollomon equation fitted to them to predict the forming limit curves. In a previous study, we showed experimentally that the Hollomon equation exponent, typically 0.07, used in such limit strain predictions is too high and should be approximately 0.04. Other authors have obviously used such a high value because they have compensated for the reduction of limit strains near the plane strain by increasing the Hollomon equation exponent. The reduction of limit strains near the plane strain occurs, as the Marciniak-Kuczynski theory, which the aforementioned authors have used, assumes a local inhomogeneity or a thinner section in the sheet to explain the local necking in stretch forming. In this study, it is shown experimentally that the Hollomon equation exponent in both the rolling and transverse directions is very close to 0.04. It is shown further that the Hollomon or Voce equations do not describe very well the work-hardening of the AA 3104-H19 alloy in either the rolling or transverse direction. 相似文献