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11.
During the past 20 years, findings have indicated that nature plays an active role in helping people recover from stress and fatigue. Two of the most cited theories in this field are Rachel and Stephen Kaplan's theory of recovery from Directed Attention Fatigue in nature and Roger Ulrich's theory of aesthetic and affective responses to natural environments and stress recovery. One aim of the present study is to test whether being outdoors in a green recreational environment causes people to be more focused, compared to being in a room indoors (in line with hypotheses suggested by the Kaplans). Another aim is to test whether people experience stress reduction, i.e. as evidenced by changes in blood pressure and heart rate, if they are placed in an environment with many green elements (in line with hypotheses suggested by Ulrich). The overall study design is that of an intervention study. Fifteen elderly persons living at a home for very elderly people participated. Their powers of concentration, blood pressure and heart rate were measured before and after an hour of rest in a garden or in an indoor setting. Seven elderly people were randomly chosen to have their first series of tests in a garden, while eight elderly people had their first series of tests indoors. The results indicate that powers of concentration increase for very elderly people after a visit to a garden outside the geriatric home in which they live, compared to that after resting indoors in their favourite room. The results did not show any effects on blood pressure or heart rate. It is suggested that having a one-hour rest outdoors in a garden setting plays a role in elderly people's powers of concentration, and could thereby affect their performance of activities of daily living. One important factor in this study was that both the outdoor environment and the indoor environment at the home were highly valued by participants. 相似文献
12.
Simulations and designs are presented of conventional and periodic SO2 absorption from exhaust gases using salt water as absorption solvent. Operating conditions resemble those of a maritime operation, involving relatively small amounts of SO2, so the separation is in the linear region. The advantages of periodic operation, as already demonstrated for conventional distillation remain valid for absorption processes: Less tall towers, than staged towers are possible, or substantially less salt water is required for the process employing periodic cycling. 相似文献
13.
Mensura Junuzovic Patrik Midlöv Sara Larsson Lönn Anders Eriksson 《Accident; analysis and prevention》2013
Since any firearm injury is potentially lethal, it is of great interest to prevent firearm incidents. This study investigated such incidents during hunting and Swedish hunters’ safety behaviour. A 48-item questionnaire was posted to a random sample of 1000 members of the Swedish Association for Hunting and Wildlife Management. The questions considered demographics, hunting experience/hunting habits/safety behaviour/attitudes and experience of careless weapon handling, hunters’ weapons and safety behaviour relating to weapons, health status, firearm incidents and their preventability, and personal comments on the questionnaire. The response rate was almost 50%. The mean age of the responders was 54 years; 5% were females. Almost none (1%) reported hunting under the influence of alcohol. Young age and male sex were positively associated with risk behaviour, although the presence of multiple risk behaviours in the same responder was not common. A very high degree of compliance with Swedish laws regarding weapon storage was reported. One-quarter of the responders had witnessed a firearm incident caused by another hunter, which in most situations did not result in human injury or death. An unsafetied weapon was the most common reported “cause” of these incidents. Experience of a firearm incident was not uncommon and the majority of the responders considered the incident in question to be preventable. This study provides a picture of the possible risk behaviour among hunters and the results suggest that future prevention work should target safer weapon handling. 相似文献
14.
15.
High-density atomic hydrogen, which is believed to be a quantum liquid, can be formed by heterogeneous catalysis at the surface of hydrogen-transfer metal oxide catalysts. Extensive studies have been made of the hydrogen phase named H(1), with interatomic distance of 150 pm found by Coulomb explosion measurements. This bond distance corresponds to a material density of 0.5–0.7 kg dm−3. The use of this material as fusion target for inertial confinement fusion (ICF) is proposed in J Fusion Energy 2008;27:296–300. A much denser hydrogen (deuterium) material D(−1) also exists with an interatomic distance of 2.3 pm. This material is probably the inverse of metallic D(1), where nuclei and electrons exchange their roles. The ICF process would be greatly simplified if the intended initial multi-laser compression stage was not necessary. The close-packed density of D(−1) is calculated from the bond distance as >130 kg cm−3. This is much higher than that required for “fast ignition” laser-driven fusion (>0.3 kg cm−3). It may mean that a method already exists to prepare dense hydrogen fuel for small-scale laser-driven fusion. The high energy particles observed experimentally (up to 150 keV/atomic mass unit in the peak or 109 K) indicate that high energy processes exist at relatively low laser intensities. 相似文献
16.
Patrik Eklund Manuel Ojeda-Aciego 《Electronic Notes in Theoretical Computer Science》2002,66(5):104-105
This part of the volume contains the papers accepted for presentation at the workshop on Unification in Non-Classical Logics (UNCL), co-located with ICALP 2002, which took place on July 12, 2002 in M 'alaga, Spain.The workshop was concerned with one of the most promising areas of research on non-classical logics and its applications. Unification in non-classical logics, with various approaches to handling generalised terms, has drawn more and more attention in recent years. So far, most popular lines of research include fuzzy unification of (conventional) databases and the use of fuzzy concepts in information retrieval.This workshop was conceived as a forum for the exchange of ideas relevant for the concept of unification in non-classical logics, including, but not limited to, the topics of:
- • Unification in multiple-valued and fuzzy logic programming.
- • Unification based on similarities and fuzzy equivalence relations.
- • Categorical unification.
- • Practical use of non-classical unification, e.g. in expert systems and information retrieval.
17.
This study describes the utilization of acoustic cues in communication of emotions in music performance. Three professional guitarists were asked to perform 3 short melodies to communicate anger, sadness, happiness, and fear to listeners. The resulting performances were analyzed with respect to 5 acoustic cues and judged by 30 listeners on adjective scales. Multiple regression analysis was applied to the relationships between (a) the performer's intention and the cues and (b) the listeners' judgments and the cues. The analyses of performers and listeners were related using C. J. Hursch, K. R. Hammond, and J. L. Hursch's (1964) lens model equation. The results indicated that (a) performers were successful at communicating emotions to listeners, (b) performers' cue utilization was well matched to listeners' cue utilization, and (c) cue utilization was more consistent across different melodies than across different performers. Because of the redundancy of the cues, 2 performers could communicate equally well despite differences in cue utilization. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
18.
Olga Guseva Patrik Schmutz Thomas Suter Oliver von Trzebiatowski 《Electrochimica acta》2009,54(19):4514-10532
A mathematical model for simulating a passive aluminium (Al) surface with a pit in which active electrochemical metal dissolution occurs has been developed. The model includes hydrolysis products of Al and the species obtained as a result of homogeneous reactions between chloride and Al3+ ions and Al hydrolysis products. The model does not assume the equilibrium state in solution: all terms in homogeneous reactions are treated explicitly using kinetic constants taken from the literature. The validity of assuming reaction equilibrium has been addressed. Solution potential values and species concentrations are predicted for different dissolution current densities. The acidity in the pit is explained by the hydrolysis of Al3+; an analytical expression for the pH values at the pit bottom for a given dissolution current density is presented.The model is applied to a real capillary geometry used in electrochemical microcell experiments. It was found that for rcap/rpit < 100, where rcap and rpit are the capillary end and pit radii, respectively, the insulating capillary wall affects the species concentrations and the solution potential. Moreover, for rcap/rpit < 20, the shape of the capillary, which might not be cylindrical, should be taken into account. 相似文献
19.
Heidi Markus Päivi Mäki-Arvela Narendra Kumar Natalya V. Kul’kova Patrik Eklund Rainer Sjöholm Bjarne Holmbom Tapio Salmi Dmitry Yu. Murzin 《Catalysis Letters》2005,103(1-2):125-131
The natural lignan hydroxymatairesinol was hydrogenolysed to a potential anticarcinogenic substance matairesinol over different carbon-supported palladium catalysts. The reaction was conducted in 2-propanol at 70 °C under hydrogen flow in a stirred glass reactor. The catalysts were characterised by N2-physisorption, CO pulse chemisorption and pH measurement of aqueous catalyst slurries. The most active catalyst (Degussa-Hüls) gave yields of matairesinol over 90% in 4 h. It was concluded that the acidity of the catalyst had a profound influence on the reaction rate. 相似文献
20.
Patrik Fauser Jens Christian Tjell Hans Mosbaek Kim Pilegaard 《Petroleum Science and Technology》2000,18(9):991-1007
A method for identifying and quantifying bitumen particles, generated from the wear of roadway asphalts, in aerosol and soil samples has been developed. Bitumen is found to be the only contributor to airborne particles containing organic molecules with molecular weights larger than 2000 g pr. mol. These are separated and identified using High Performance Gel Permeation Chromatography (HP-GPC) with fluorescence detection. As an additional detection method Infra Red spectrometry (IR) is employed for selected samples, The methods have been used on aerosol, soil and other samples. 相似文献