Increase of the Short-Term Fluctuation of the Differential Light Threshold Around a Physiologic Scotoma

1989 ◽  
Vol 107 (4) ◽  
pp. 417-420 ◽  
Author(s):  
Ivan Oliver Haefliger ◽  
Josef Flammer
Keyword(s):  
2015 ◽  
Vol 23 (2) ◽  
pp. 268
Author(s):  
Xinxin LU ◽  
Yidong TU

1989 ◽  
Vol 28 (4) ◽  
pp. 331-335
Author(s):  
A.A. Edebiri ◽  
D.S. Mack ◽  
D.J. McDonald ◽  
J. Philips

Radiocarbon ◽  
2007 ◽  
Vol 49 (2) ◽  
pp. 473-479 ◽  
Author(s):  
Hiromasa Ozaki ◽  
Mineo Imamura ◽  
Hiroyuki Matsuzaki ◽  
Takumi Mitsutani

In order to investigate the regional atmospheric radiocarbon offset, accelerator mass spectrometry (AMS) 14C measurements were made on 5-yr increments of a Japanese wood sample dendrochronologically dated to 820–436 BC. The 14C data from the Japanese tree-ring samples were compared with the IntCal04 calibration curve (Reimer et al. 2004). In most parts, the differences between IntCal04 and 14C dates in the Japanese tree-ring samples were within experimental statistical errors. At around 680 BC, however, significant differences of up to 100 14C yr were observed. These differences may indicate either regional offsets in Japan or the short-term fluctuation of a subdecadal timescale in atmospheric 14C variations.


Radiocarbon ◽  
2014 ◽  
Vol 56 (02) ◽  
pp. 655-665
Author(s):  
John Meadows ◽  
Nicoletta Martinelli ◽  
Marie-Josée Nadeau ◽  
Elodia Bianchin Citton

Two floating tree-ring chronologies were developed from oak timbers recovered during salvage excavations of a pre-Roman wharf in Este, a prominent center of the Veneti people, who lived in northeastern Italy during the Iron Age. Wiggle-match radiocarbon dating shows that one chronology spans the 10th and 9th centuries cal BC, and that the waterfront was probably built ∼800 cal BC. The second chronology apparently spans most of the 7th century cal BC, and is associated with a phase of construction about 2 centuries after the first. One of the samples gave what appeared to be anomalous14C results that may best be explained as evidence of a short-term fluctuation in atmospheric14C level, which can be seen in short-lived samples but is not apparent in the decadal or bidecadal calibration data. Both chronologies cover periods for which there are no other tree-ring chronologies in this region, and could become key to refining the local Iron Age chronology.


1989 ◽  
Vol 108 (6) ◽  
pp. 748-749 ◽  
Author(s):  
PAOLO BRUSINI ◽  
GIOVANNI DELLA MEA ◽  
CLAUDIA TOSONI ◽  
FLAVIA MIANI
Keyword(s):  

1990 ◽  
Vol 41 (6) ◽  
pp. 747 ◽  
Author(s):  
LC Bowling ◽  
K Salonen

The annual heat budgets and maximum thermal stabilities achieved by small Finnish forest lakes are considerable for lakes of their size. Heat uptake is rapid during the brief period of vernal circulation, with the latent heat of fusion of ice contributing substantially to this. Heating then slows, with maximum heat contents and thermal stabilities occurring around early August. Absorption of solar radiation by the dystrophic waters, effective shelter from wind-induced turbulence, and considerable relative depths all combine to prevent mixing of heat much below the surface 2 m of most study lakes. Birgean wind-work values therefore remain low, and cold hypolimnetic waters occupy much of the lake volume. The lakes also respond quickly to meteorological change, which causes considerable year-to-year variation, and some short-term fluctuation, in their heat budgets and maximum stabilities. The lakes' small size and shallow thermal stratification may contribute to this.


2019 ◽  
Vol 19 (5) ◽  
pp. 1421-1439
Author(s):  
Shaowei Wang ◽  
Yingli Xu ◽  
Chongshi Gu ◽  
Qun Xia ◽  
Kun Hu

The safety of a high concrete arch dam should be rapidly diagnosed from different angles. Displacement is an actual comprehensive reflection of the arch dam, and it is very important to diagnose the overall deformation behaviour by displacement-based mathematical monitoring models. In this article, based on the spatial association validation of the measured displacement of two high arch dams by the empirical orthogonal function decomposition and the Pearson correlation analysis, two spatial association–considered mathematical models were proposed for the dam displacement of multimonitoring points: one model for the long-term balanced relationship and one model for the short-term fluctuation. To diagnose the abnormality of the dam long-term spatial association, each displacement time series of the multimonitoring points on the dam body with strong spatial associations was decomposed by wavelet multiresolution analysis, and the decomposed high-frequency components, which had the same periodicity as the causal factors of the reservoir water level or air temperature, were determined to establish the cointegration monitoring model. The second model was a combination prediction model, with two sub-models established from the modelling angles of the hydraulic, seasonal and time causal factors and the adjacent point displacement factors, and this second model was mainly used for identifying dam short-term local abnormal deformation behaviour. Engineering examples show that the deformation behaviour of an arch dam under normal conditions has strong spatial associations. The two proposed models have high accuracy and interpreting ability and can effectively reduce the number of needed monitoring models.


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