scholarly journals Populations dynamics in Northern Eurasian forests: a long-term perspective from Northeast Asia

2020 ◽  
Vol 2 ◽  
Author(s):  
Junzo Uchiyama ◽  
J. Christopher Gillam ◽  
Alexander Savelyev ◽  
Chao Ning

Abstract

Antiquity ◽  
2017 ◽  
Vol 91 (355) ◽  
pp. 57-73
Author(s):  
Laure Salanova ◽  
Philippe Chambon ◽  
Jean-Gabriel Pariat ◽  
Anne-Sophie Marçais ◽  
Frédérique Valentin

Abstract


2018 ◽  
Vol 115 (45) ◽  
pp. 11543-11548 ◽  
Author(s):  
Jan Altman ◽  
Olga N. Ukhvatkina ◽  
Alexander M. Omelko ◽  
Martin Macek ◽  
Tomas Plener ◽  
...  

Determination of long-term tropical cyclone (TC) variability is of enormous importance to society; however, changes in TC activity are poorly understood owing to discrepancies among various datasets and limited span of instrumental records. While the increasing intensity and frequency of TCs have been previously documented on a long-term scale using various proxy records, determination of their poleward migration has been based mostly on short-term instrumental data. Here we present a unique tree-ring–based approach for determination of long-term variability in TC activity via forest disturbance rates in northeast Asia (33–45°N). Our results indicate significant long-term changes in TC activity, with increased rates of disturbances in the northern latitudes over the past century. The disturbance frequency was stable over time in the southern latitudes, however. Our findings of increasing disturbance frequency in the areas formerly situated at the edge of TC activity provide evidence supporting the broad relevance of poleward migration of TCs. Our results significantly enhance our understanding of the effects of climate change on TCs and emphasize the need for determination of long-term variation of past TC activity to improve future TC projections.


1990 ◽  
Vol 123 ◽  
pp. 463-468
Author(s):  
M. Matsuoka ◽  
N. Kawai ◽  
T. Imai ◽  
M. Yamauchi ◽  
A. Yoshida ◽  
...  

AbstractWe propose an X-ray all sky monitor for Japanese Experimental Module (JEM) on the space station. Considering practical circumstances, we show as a case study that the all sky monitor with slit hole cameras is most promising for monitoring the short-term and long-term X-ray transients. We call this all sky monitor as MAXI (Monitor of All-sky X-ray Image). Position determination of gamma-ray bursts could be achieved with accuracy less than one degree observing the X-ray component of the burst. Weak X-ray sources such as active galactic nuclei could be also monitored with time resolution less than one day. The X-ray all sky monitor will work to discover X-ray novae and transient phenomena and give us the alarm for further detailed observations. The obtained data will be also used for archival study.


1990 ◽  
Vol 212 ◽  
Author(s):  
R. J. Finch ◽  
R. C. Ewing

ABSTRACTUranyl oxide hydrates, formed by the alteration of uraninite, are natural analogues for the long-term corrosion products of spent fuel in a geologic repository under oxidizing conditions. The uranyl oxide hydrates may be represented by the general formula:Pb-bearing hydrates require the addition of a neutral uranyl group into the structural sheet (UO2(OH)2) for each interlayer Pb ion. Distortion of the structure associated with the additional uranyl groups is reduced by replacing two structural hydroxyls with a structural oxygen and a molecular water. The general formula for the Pb-uranyl oxide hydrates is:This hypothesis explains the paragenetic sequences:1) schoepite ➛ billietite ➛ protasite ➛ bauranoite2) schoepite ➛ vandendriesscheite ➛ fourmarierite ➛ masuyite ➛ wölsendorfite3) schoepite ➛ vandendriesscheite ➛ fourmarierite ➛ ± masuyite ➛ sayrite ➛ curite, and indicates that, under relatively high pH conditions, schoepite will not be the long-term solubility-controlling phase for uranium in uranium-rich groundwaters.


2011 ◽  
Vol 26 (15) ◽  
pp. 1800-1812 ◽  
Author(s):  
Jayaram Dadda ◽  
Eckhard Müller ◽  
Susanne Perlt ◽  
Thomas Höche ◽  
Paula Bauer Pereira ◽  
...  

Abstract


2001 ◽  
Vol 1 (2) ◽  
pp. 31-61 ◽  
Author(s):  
Shin-wha Lee

There are two opposing views regarding the prospects of establishing a regional environmental regime in Northeast Asia. The first view considers the environment as a dependent variable of progress towards regionalism and suggest that regional environmental cooperation is impeded by political rivalries, historical animosities and economic disparities among Northeast Asian countries. The opposing view treats the environment as an independent variable of sustainable regionalism. The premise of this view is that inter-state environmental cooperation can become a confidence building measure that will pave the way for improved regional relations. Regardless of which view proves in the end to be right, the high environmental interdependence of countries in Northeast Asia makes it imperative to create a framework to promote greater cooperation within the region. Given that the region lacks institutions for region-wide dialogue and cooperation, the formation of an effective regional environmental regime will be a long-term process. However, the process itself is pivotal as it can increase dialogue and exchanges from which a regional environmental regime can evolve, and hopefully, if given the political opportunity, will promote security and peace in the region.


2019 ◽  
Vol 9 (2) ◽  
pp. 75-97
Author(s):  
Wai Ting

AbstractThe rise of China has aroused heated debates on whether the country would become the “revisionist” power in challenging the supreme position of the “status quo” power, the United States. This paper aims to examine whether the rise of China would, firstly, empower Beijing to solve the long-term crisis in the Korean Peninsula, and secondly, complicates the picture in solving the difficult historical and political issues in Sino-Japanese relations. It is argued that the increasing economic and military capabilities of China are not instrumental in fostering significant changes within North Korea and in monitoring the external behavior of its leaders. A more nationalistic China which lacks soft power also hinders a favorable solution to the challenges of Sino-Japanese relations.


1980 ◽  
Vol 88 ◽  
pp. 269-270
Author(s):  
S. Kříž

RX Cas appers to be a long-period Algol-like binary with very fast mass exchange (Struve 1944). In the period 1975-1977, this star was observed photometrically by Arsenijevič, Grygar, Harmanec, Horn, Koubský, Kříž and Pavlovski at Hvar Observatory (Yugoslavia) and by Zverko at Skalnaté Pleso Observatory (Czechoslovakia). The resulting UBV light curves seem to be rather peculiar, for the following reasons:1) Combining our observations with the older ones, we obtain the following formula for the times of minima: The period increase is surprisingly high.2) The scatter of observed points is considerable (about 0.2 mag.) and cannot be caused by observational errors. It corresponds to short period light variations on the time scale of several days.3) After J.D. 24422660, the brightness of the whole system decreased in all colours. This decrease is about 0.2 mag. in V colour and 0.5 mag. in U colour. Only after J.D. 2442900 the brightness increased again. Such a behaviour confirms the reality of old observations by Gaposchkin (1944) and Martynov (1950) who found a long-term light variation with a period of approximately 500 days.4) The part of the light curve around the phase 0.75 is definitely much lower than the corresponding part around the phase 0.25. This effect is most pronounced in the ultraviolet; the depression around the phase 0.75 is much deeper than the secondary minimum. This behaviour is opposite to the behaviour of dwarf novae. Instead of a bright shoulder connected with a bright spot, we observe some darkening.


2020 ◽  
Author(s):  
Noh-Hun Seong ◽  
Sungwon Choi ◽  
Donghyun Jin ◽  
Daeseong Jung ◽  
Kyung-soo Han

<p>Surface broadband albedo is one of the climate variables that understand Earth’s radiation budget. Currently, the polar-orbit satellite-derived surface broadband albedo products are retrieved by several organizations. As there are many kinds, it is necessary to identify the characteristics of each products. In this study, we were to compare representative products for long-term that the albedo products based on polar-obit satellite such as moderate resolution imaging spectroradiometer (MODIS) and the Copernicus Global Land Service (CGLS). We studied the Northeast Asia region where the land type remains unchanged from 2000 to 2018. The overall trend of the two products was similar. However, differences occurred depending on the land types and season. The relatively high value of MODIS albedo was calculated in winter because it was sensitive to the snow. In other seasons, the CGLS albedo was higher than the MODIS albedo. The MODIS albedo was calculated higher than CGLS albedo for all land types except forest. The comparison results showed that caution should be given before operational use of the albedo data sets in these regions.</p>


1971 ◽  
Vol 6 (2) ◽  
pp. 153-156 ◽  
Author(s):  
Karl Borch

1. At an earlier ASTIN Colloquium participants were invited to present notes on problems which they considered as important but unsolved. There was little response to this invitation, presumably because a problem, once it is well formulated, is almost solved.In this Note I do not present any new problems. In stead I try to outline a framework which may be useful for analysing different risk problems and seeing them in their proper perspective. In my view, a framework of this kind is urgently needed to place today's actuarial work on a sound foundation.2. In general an insurance contract will define two stochastic processes. We lose little by assuming that the processes are discrete, and describing them in the following manner:(i) The payment process: x0, x1 … xt …, where xt is the amount which the company pays to settle claims in period t, or at time t.(ii) The premium process: p0, p1 … pt …, where pt is the premium which the company receives in period t, or at time t.If the contract is concluded at time t = o, the Principle of Equivalence requires thatFor the typical short-term contract with premium payable in advance (i) will reduce to3. For a long-term insurance contract one usually requires that the inequalityshall hold for all τ. This means that the company must never be a net creditor of its customer.


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