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981.
Geo Clausen Linda Carrick P. Ole Fanger Sun Woo Kim Torben Poulsen Jens Holger Rindel 《Indoor air》1993,3(4):255-262
The relative importance of sensory air pollution, thermal load and noise was studied under controlled conditions in two identical environmental chambers. In one chamber subjects were exposed to various levels of either thermal load or poor indoor air quality. For each condition tested in this chamber, the subjects were exposed to a number of noise levels in an adjacent chamber with neutral thermal conditions and good indoor air quality in order to determine a noise level causing the same degree of discomfort. A total of 68 comparisons of the conditions in the two chambers were made by the same group of 16 subjects after one-minute exposure in each chamber. In the operative temperature range of 23–29°C, a 1°C change in operative temperature was found to have the same effect on human comfort as a change in perceived air quality of 2.4 decipol or a change in noise level of 3.9 dB. For levels of perceived air quality up to 10 decipol, a 1 -decipol change in perceived air quality had the same effect on human comfort as a change in noise level of 1.2 dB. A relationship between traffic noise level and percentage dissatisfied was established 相似文献
982.
The set of cost inputs for which an optimal solution of the dynamic lot size model remains valid is called stability region. The size of this region may be viewed as a measure of robustness of a solution. It is an expectation that the stability regions shrink with growing time horizons and that they are monotonous in this sense. In the present paper several sufficient conditions implying monotonicity will be studied. The conditions cover the existence of planning and forecast horizons and generalize the results of a previous paper in wich monotonicity results were presented for the case of ordinary planning horizons. 相似文献
983.
Özgün Paker Jens Sparsø Niels Haandbæk Mogens Isager Lars Skovby Nielsen 《The Journal of VLSI Signal Processing》2004,37(1):95-110
This paper describes a low-power programmable DSP architecture that targets audio signal processing. The architecture can be characterized as a heterogeneous multiprocessor consisting of small instruction set processors called mini-cores as well as standard DSP and CPU cores that communicate using message passing. The mini-cores are tailored for different classes of filtering algorithms (FIR, IIR, N-LMS etc.), and in a typical system the communication among processors occur at the sampling rate only.The mini-cores are intended as soft-macros to be used in the implementation of system-on-chip solutions using a synthesis-based design flow targeting a standard-cell implementation. They are parameterized in word-size, memory-size, etc. and can be instantiated according to the needs of the application. To give an impression of the size of a mini-core we mention that one of the FIR mini-cores in a prototype design has 16 instructions, a 32-word × 16-bit program memory, a 64-word × 16-bit data memory and a 25-word × 16-bit coefficient memory.Results obtained from the design of a prototype chip containing mini-cores for a hearing aid application, demonstrate a power consumption that is only 1.5–1.6 times larger than a hardwired ASIC and more than 6–21 times lower than current state of the art low-power DSP processors. This is due to: (1) the small size of the processors and (2) a smaller instruction count for a given task. 相似文献
984.
随着无线电技术的飞速发展和无线电设备的广泛应用,有一些无线电监测站希望拥有能监测高于3GHz频段的设备。在此,笔者给大家介绍一下德国普拉特公司(Plath GmbH)所开发和集成的ELEC 2C山顶型宽频带无线电监测站。 相似文献
985.
The present article reports 3 studies that demonstrate the influence of overt behavior on recognition and elucidates the theoretical basis for such an influence. In 2 experiments it was found that participants who were induced to nod while incidentally encoding positive and negative adjectives were more likely to recognize positive adjectives, whereas participants who were induced to shake their heads were more likely to recognize negative words. In a third experiment, with a double-task procedure, it was shown that when encoding was accompanied by head movements that were compatible with words, participants were better at performing the secondary task than when words and head movements were incompatible. These findings suggest that performing incompatible motoric and conceptual tasks concurrently requires more cognitive capacity. Where this capacity is allocated and when it is withdrawn depends on the characteristics of the task. Implications of this mechanism for different phenomena in social psychology (e.g., facial feedback and masking of emotional displays) are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
986.
Andersen Maibritt B.; Zimmer Jens; Sams-Dodd Frank 《Canadian Metallurgical Quarterly》1997,111(6):1205
Gerbils show a postischemic increase in locomotor activity that correlates to the extent of neuron loss in the hippocampal CA1 subfield. It has been suggested that this hyperactivity is predictive of neuron loss in the CA1. In this study the correlation between postischemic hyperactivity and neuron loss in several hippocampal subfields was investigated, and the theory that the hyperactivity is due to a reduced ability for spatial navigation was evaluated. Significant correlations were found between hyperactivity and neuron loss in several hippocampal subfields; the correlation was stronger for the CA3 than for the CA1 subfield suggesting that postischemic hyperactivity can be used as a predictor of neuron loss in the CA3 rather than in the CA1. From observations of the pattern of hyperactivity within the test arenas and during the test period, this study challenges the spatial mapping theory of postischemic hyperactivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
987.
Stephan P. A. Sauer John R. Sabin Jens Oddershede 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1995,100(4):458-463
Using the random phase approximation, we have calculated the total and directional components of the mean excitation energy for stopping (I0) and the stopping anisotropy (
) as well as the first moment (I1) of the dipole oscillator strength distribution for 20 small molecules and molecular ions containing 6 to 30 electrons. We find that for excitations polarized orthogonal (perpendicular) and parallel to the molecular high symmetry axis I0O > I0P for all linear molecules, while I1O < I1P for all molecules other than HF. We note that the Bloch rule holds only for small, compact molecules, and that the Bragg rule should not be used to determine the mean excitation energies of the molecules that we consider here. The stopping anisotropy is positive for all but the C3v molecules, and is largest for the linear, rod-shaped molecules. 相似文献
988.
Patrik Fauser Jens Christian Tjell Hans Mosbaek Kim Pilegaard 《Petroleum Science and Technology》2002,20(1):127-141
Tire and bitumen particle concentrations are determined in aerosol and soil samples. They each constitute about 5 wt-% of the total suspended particulate matter (TSP) in inner city air, collected with a Berner low pressure impactor, 5 m from a road. The particle size distribution shows that 92% of the mass of airborne particulate tire debris have aerodynamic diameters smaller than 1 µm. The mean aerodynamic diameter is about 1 µm for the bitumen particles. This size range enables the possibility for far range transport and inhalation by humans. Soil concentrations in the vicinity of a highway indicate an approximate exponential decrease with increasing distance from the road. Constant values are reached after about 5 m for the tire particles and 10 m for the bitumen particles. Concentrations in soil that has not been touched for at least 30 years show a decrease in tire concentration by a factor of 30 when moving from the top soil to a depth of 3 cm. The bitumen concentration is approximately constant to a depth of 10 cm. 相似文献
989.
Jens O. Riis 《International Journal of Project Management》1985,3(2):68-72
Substantial inertia is frequently experienced in the initiation phase of a project, and in order to overcome that inertia, attention must be paid to four critical factors: time and energy, willpower, opportunity and the project's ‘basic concept’. These four factors are explained, and their application in different countries is discussed with reference to Hofstede's cultural dimensions. 相似文献
990.
Jens Hartkopf Helmut F. Erbersdobler 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1995,201(1):27-29
Zusammenfassung Es wurden Modellversuche zur Bildung von N-Carboxymethyllysin (CML) an erhitzten Wurstbrätproben mit unterschiedlichen Zusätzen durchgeführt. In der Reaktion des Lysins mit Ascorbat wird offensichtlich mehr CML gebildet als in der Reaktion des Lysins mit Glucose. Ein Zusatz von Ascorbat in handelsüblicher Konzentration erhöhte den CML-Gehalt im Wurstbrät auf 35 mg, der von Glucose in sogar höherer Konzentration dagegen nur auf 23 mg, gegenüber 17 mg CML/kg Rohprotein in der Kontrollprobe. Ein Zusatz von Diphosphat in handelsüblicher Konzentration neben Glucose bewirkte eine signifikante Steigerung der CML-Gehalte von 23 mg auf 30 mg CML/kg Rohprotein. Die gesetzlich zugelassene Höchstmenge an Nitrit übte dagegen keinen Einfluß auf die CML-Bildung aus (21 mg CML/kg Rohprotein). Die Absolutwerte sind generell gering, verglichen mit CML-Gehalten in anderen Lebensmitteln wie Milchprodukten.
Model experiments with sausage meat on the formation of N-carboxymethyllysine
In model experiments the influence of ingredients normally used for sausage production to a meat homogenate on the formation of N-carboxymethyllysine (CML) was investigated. The formation of CML is obviously more promoted from the reaction of ascorbate with lysine than from that of glucose with lysine. The addition of ascorbate in a practical concentration yielded 35 mg, the addition of glucose only 23 mg compared to 17 mg CML/kg protein in the control sample. The addition of diphosphate in a practical concentration besides glucose significantly increased the CML values from 23 mg to 30 mg CML/kg protein. On the other hand, nitrite did not enhance the formation of CML (21 mg/kg protein) in the sausage when used in concentrations usually applied in meat processing. Generally the values found in the meat products are quite low compared to data in other foods like milk products.相似文献