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1.
Li  Chunlin  Cai  Qianqian  Luo  Youlong 《Cluster computing》2022,25(2):1421-1439

Improper data replacement and inappropriate selection of job scheduling policy are important reasons for the degradation of Spark system operation speed, which directly causes the performance degradation of Spark parallel computing. In this paper, we analyze the existing caching mechanism of Spark and find that there is still more room for optimization of the existing caching policy. For the task structure analysis, the key information of Spark tasks is taken out to obtain the data and memory usage during the task runtime, and based on this, an RDD weight calculation method is proposed, which integrates various factors affecting the RDD usage and establishes an RDD weight model. Based on this model, a minimum weight replacement algorithm based on RDD structure analyzing is proposed. The algorithm ensure that the relatively more valuable data in the data replacement process can be cached into memory. In addition, the default job scheduling algorithm of the Spark framework considers a single factor, which cannot form effective scheduling for jobs and causes a waste of cluster resources. In this paper, an adaptive job scheduling policy based on job classification is proposed to solve the above problem. The policy can classify job types and schedule resources more effectively for different types of jobs. The experimental results show that the proposed dynamic data replacement algorithm effectively improves Spark's memory utilization. The proposed job classification-based adaptive job scheduling algorithm effectively improves the system resource utilization and shortens the job completion time.

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2.
The archaeologists excavate the historic site and analyze data from the excavation site. Therefore, they study about the past affairs and circumstances unknown to the world. These data are composed of stones, plants, bones and geological features, which are stored in separate files according to the fields of study. It is important to mention that this information become the first step toward the solution of some hypothesis in Archaeology. Therefore, we need the system that can not only support integrated environment to find clues of the past, but also manage existing artifact data systematically and grasp relationships among the data. In this paper, we modeled the time, which is used in archaeology and geology, and built an entity relationship database to store Paleolithic data excavated in Jungwon region site of the Republic of Korea as one resource, which seem to give a base for integrated research and relationships in archaeology. In addition, we developed the Graphic User Interface that allows various users to connect to the established system through the web.  相似文献   

3.
The painting matter of the “back to back bison's panel” of Lascaux was examined and analysed by electron microscopy in order to understand the know-how of Magdalenian artists. The observation of several samples coming from specific areas of the two bisons give an access to the nature of the used pigments, to the preparation mode used to obtain various colours and also to the application mode. Thanks to this physicochemical approach, we can make hypotheses about the mind and the gestures of the artists.  相似文献   

4.
Since the middle of 1970s, one rock-shelter, six caves and one open archaeological site have yielded several hominid fossils. Among them, fossils from Yonggok, Mandal, Sangsi and Hungsu cave sites are useful to reconstruct the general shape of the Upper Pleistocene Hominids in Korea. The main study of this paper is to focus on the reconstruction of the general shape of the upper Pleistocene hominids, and to examine the cause of cranial changes from the late upper Paleolithic to Mesolithic period in Korea. Biomechanical principles are also applied to reconstruct the social activity of the upper Paleolithic man in Korea. In addition, it is assumed that main proponent of Paleolithic cultures in Korea might be Homo sapiens rather than any other species. Based on the anatomical characteristics of skull, the axillary border of the scapular and the midshaft of the femur, general appearance of Homo sapiens during the Pleistocene in Korea could be reconstructed.  相似文献   

5.
The term “precision”, involving the contact between the tips of thumb and the index is generally attributed to humans, tool use and associated with morphological criteria. Identified in fossils, those criteria are used to assert that they manipulated tools. Observations of 69 individuals belonging to Catarrhines and Platyrrhines allowed us to quantify surfaces of fingers used during simple tasks of grasping both small and large objects, as well as during complex tasks of proto-tool and tool use. We concluded that precision grasping is not peculiar to humans and that it is not systematically linked to tool use. These results allowed us to discuss morphological traits used till now to deduce precision and tool use from the fossils. Besides, our analyses let appear a recurrent proximity between the capuchins and the humans, species distant in a phylogenetic point of view, suggesting the possible existence of functions and close behaviours in spite of great genetic distinctions.  相似文献   

6.
Hundreds samples of the charcoals and waterlogged woods excavated from three late Paleolithic sites (Suyanggae, Gunang-gul and Sorori) in the Jungwon Region in Korea were analyzed to reconstruct the vegetation and paleoclimate in the region. Analyzed charcoal samples from the Suyanggae site show that the climate was cold in the lower part and it became more warm and dry in the upper part. From the Gunang-gul site, only Picea spp. was identified, indicating cool climates. From the Sorori site, two species were found; Alnus spp. (95%) and Ulmus spp. (5%). No conifers were discovered. The species composition indicates that the climate condition of central Korean peninsula around 8,800 BP was little cooler and wetter condition.  相似文献   

7.
The Lias and Dogger series in the southern Paris Basin outcrops are precisely dated following the ammonite biozonation scale. In these series, the depositional environment context is accurately identified and thus various isopic zones can bee recognized. From the outcrop study, the depositional sequence and the tectonics events are also distinguished. The poorly dated subsurface data should be not anymore interpreted as diagraphic signatures, with the traditional peak to peak correlation. They now need to be analysed according to the geodynamic evolution of each isopic zone. The Liassic transgressive series (in the Armorican continent) and the Dogger platforms numerous carbonate bodies are correlated at biostratigraphic scale, throughout the whole southern Paris Basin. Subsequently, paleogeographic maps are established and based on depositional sequences. The basin evolution image changes radically. This shows clearly that the complexes carbonate bodies layout prohibits any depositional environment interpretation and any isopach mapping at geological stage level. If not, the carbonate platforms of different age would be amalgamated, without any connection with the reality. Over the time, paleogeographic maps show syn-sedimentary short wavelength deformations, more or less well expressed according to the local sedimentary context. During the Lias and the Dogger, three steps can be distinguished in the southern Paris Basin. Hettangian to Lower Aalenian, the progressive increase in accommodation drives to total immersion of the continental areas; the maximum of accommodation during the Middle Toarcian entails uniform sedimentary conditions. However, short wavelength deformations persist. The major accidents defining the isopic zones are mainly North-South oriented. Middle Aalenian to Middle Bathonian, isopic zones are contrasted, controlled by the North-South accidents but also the North West-South East ones ; the variable accommodation allowed the development of regional sedimentary gaps and shallow limestone progradations on a marly area (so called “Sillon marneux”) ; tectonics events correspond to the Tethyan and the North Sea riftings influences. Upper Bathonian to Upper Oxfordian, the North West-South East tectonics accidents are particularly active; this tectonic phase could be associated to the thermal event, described in the Paris Basin and announcing the Malm depositional environment.  相似文献   

8.
Small heat shock proteins (sHSPs) act as molecular chaperones and are widely distributed in all kinds of organisms. Comparative analysis revealed that an orthologous shsp was present during insect evolution. Here, hsp21.8b, one insect orthologous shsp, had been identified in Tribolium castaneum. Quantitative real‐time PCR illustrated that Tchsp21.8b was expressed in all developmental stages, along with the lowest expression at early embryonic stage and relative high expression at other stages especially in late eggs and late pupae. In the adult period, Tchsp21.8b exhibited the highest expression level in central nervous system and followed in elytron, epidermis, ovary and fat body. Moreover, it was upregulated 3.39‐fold in response to enhanced heat stress (45°C) for 4 hr but not to cold stress (4°C) and was upregulated by 1.73‐ to 1.94‐fold under ultraviolet (UV) exposure during 4–6 hr. It was also downregulated by 20.8%–41.8% under starvation in 3 days and had a “down‐up‐down” trend under the pathogen stresses. Larval RNA interference of Tchsp21.8b caused 40.6% insects mortality and reduced the oviposition amount by 66.0% and only 21.0% of the ds‐Tchsp21.8b eggs could hatch into larvae. These results suggested that as an orthologous shsp, Tchsp21.8b not only plays important roles in the growth, development and fecundity of T. castaneum but with the competence to resist the environment stresses, although the response is relatively weak compared to other hsps. Results from this study also uncovered the functions of the orthologous shsp in the development and anti‐stresses ability of T. castanuem. It provided more scientific evidence for revealing the physiological mechanisms of shsps of the insects and enhanced the capabilities to control different pests.  相似文献   

9.
Over the past fifteen years of research in the alpine area, the Dalmeri Rockshelter, located on the northeastern edge of the Sette Comuni Plateau (Trento, Italy), has become a key site for reconstructing the exploitation of the mountain territories by the human groups of the end of the Upper Palaeolithic. Excavations, carried out between 1991 and 2005, brought to light a sequence of Recent Epigravettian anthropic levels, which were radiocarbon dated to the Allerød interstadial. The well-preserved paleosurfaces provided the opportunity to carry out a thorough analysis on the faunal and lithic remains, enabling us to reconstruct the palaeoeconomy, the function and the internal organisation of the site. In the past five years, the discovery of a notable quantity of red ochre painted stones, which are linked to the earliest settlement phase, revealed different representations, both naturalistic paintings as well as signs. Following this discovery, the interpretation of the site began to touch the artistic-religious sphere, providing new insights into Epigravettian art.  相似文献   

10.
采用苗期缺磷和全营养对照处理,以70个中国春—野生亲缘种属二体添加系及中国春为材料,根据苗期表观遗传性状、磷吸收率和利用率相对生物量对其进行耐低磷胁迫能力筛选鉴定和基因染色体定位。结果表明:大麦4H和长穗偃麦草7E染色体上携带有耐低磷胁迫的优异基因;长穗偃麦草6E、黑麦1R和6R、卵穗山羊草4Ug和6Mg、易变山羊草4Sv染色体携带促进小麦根系生长发育的基因;拟斯比尔托山羊草5S和簇毛麦4V染色体分别携带高磷吸收率和磷利用率的基因。通过染色体工程技术,可以将携带耐低磷胁迫基因的外源染色体片段导入普通小麦,为小麦耐低磷胁迫育种和了解植物耐低磷胁迫的分子机理奠定基础。  相似文献   

11.
The human remains recovered from “Grotte supérieure de Zhoukoudian” are the best-preserved Late Pleistocene human fossils in East Asia. For decades, as the representative of the Late Pleistocene human in East Asia, the Upper Cave skulls have been playing important role in the research of origins of modern Mongoloids and American Indians. With the advance of the origin and evolution of modern humans, more attention has been paid to the details and the mechanisms for the late Pleistocene human evolution and the formation of modern human populations. Both the origin and diversification of modern humans have been stressed. Some studies further trigger the debaters on the Upper Cave Man concerning its evolutionary level and its role in the formation of modern human populations in East Asia. To further explore these problems, we examined and compared 12 non-metric features on the 3 Late Pleistocene Upper Cave skulls and 162 Holocene individuals earthed from two archaeological sites of North China (Longxian and Yanqing). Our results indicate that 8 on the 12 features have different expression patterns between Upper Cave Man and recent Chinese leading the authors to believe that more primitive expressions appeared on the Upper Cave Man than on recent Chinese populations. Based on these findings, some problems on the intragroup variation in Late Pleistocene and Holocene populations are discussed.  相似文献   

12.
The Grosse Badlhöhle (Austria, Steiermark) is the origin of one of the most perfect bone points of the early Aurignacian and one of the best perforated femurs of the same period, which can be regarded as musical instruments. Two other fragments of points raise intriguing questions on the first Homo sapiens sapiens which cannot be solved today but will contribute to future research. A review on the debate of Palaeolithic flutes will follow with experimental proofs of boring artificial holes with high quality pictures on the blow-hole and the lack of gnawing traces on the opposite face. The musical possibility of an instrument with only one hole is discussed with ethnographic analogies. Hafting, optimal conditions of strength and possible use of arrows will close the discussion on the Badlhöhle bone artefacts.  相似文献   

13.
In Korea, Quaternary deposits are characterized by marine and fluvial terrace deposits, commonly found in the coastal areas and at the sides of river valleys. The major terraces are classified into 5 different levels, i.e., alluvial plain (3-5 m asl), lower terrace (10-25 m asl), middle terrace (33-50 m asl), high terrace (55-85 m asl), and highest terrace (90-160 m asl). They were formed by the repetition of sedimentation and erosion due to sea level fluctuation and uplifting along the coastal areas during Quaternary period. The formation age of the lower marine terraces at the level of 10-20 m is interpreted to be the last interglacial (75-125 Ka, MIS = 5a-5e). The middle coastal terrace gravels distributed at the level of about 33-45 m above mean sea level and are to be formed before the last interglacial. Above coastal terrace deposits, slope deposits and paleosol layers are overlain and freezing and thawing crackings were developed in them. Major prehistory archaeological sites in the coastal areas are found in the slope deposits formed during last glaciations. The upper parts of the slope deposits are typified by paleosol layers with typical frost cracks (soil wedges) and frangipanes. As geochronological bases for subdividing Paleolithic cultures, two typical paleosol layers are useful because they are mostly found and imprinted with several horizons of frost cracks or soil wedges. The uppermost crack structures were formed under the boreal-periglacial climatic regime during the last glacial period of extremely cold-dry climate in Korea. The upper pedogenetic sediments containing frost cracks or soil wedges were formed between 24 and 17 Ka in many Paleolithic profiles. The lowermost paleosol layer with frost cracks (soil wedge), strongly attacked into hillslope sediments or last interglacial saprolite layers on the weathered basement rocks, were detected at least as old as 59-74,000 Ka. Lastly upper Paleolithic cultural layers were found in the young fluvial deposits, which had been formed since the Last Glacial Maximum (LGM). Some of them were particularly continued as late as the Pleistocene-Holocene Transition Period.  相似文献   

14.
In Bacillus subtilis, mutant alleles of the genes sms and subA partially suppress the recombination phenotype of recU cells. When present in an otherwise Rec(+) strain, Delta sms and Delta subA alleles render cells slightly sensitive to DNA-damaging agents, and impair chromosomal transformation (3- to 10-fold reduction), but do not affect plasmid transformation (less than 1.5-fold reduction). The Delta sms and Delta subA alleles were introduced into rec-deficient strains representative of the epistatic groups alpha (recF strain), beta (addA addB), gamma (recH), epsilon (recB, Delta recU and recD strains) and zeta (Delta recS). Both the Delta sms and Delta subA mutations were found to increase sensitivity to DNA-damaging agents in recF, Delta recS and addAB cells. In contrast, the Delta sms mutations decreased the sensitivity of recB, Delta recU, recD and recH cells, and the Delta subA mutation decreased the sensitivity of recB and Delta recU cells to DNA-damaging agents. Functions classified within the epistatic groups alpha, epsilon and zeta are required for intramolecular recombination, measured as plasmid transformation. The Delta sms and Delta subA mutations, which partially suppressed the recombinational repair phenotype of mutants for functions within epistatic group epsilon, enhanced plasmid transformation of recU (recB, recD) and recS cells by 10- to 20-fold. In the absence of the proteins Sms and SubA, the recombination machinery is apparently redirected towards (an) alternative pathway(s). Furthermore, the shared ability of the Delta sms and Delta subA mutations to act as indirect suppressors of recB, recU and recD mutations supports the classification of the recBUD genes within epistatic group epsilon.  相似文献   

15.
The “Grappin” or “Saint-Vincent's” cave, on the western slope of Jura, East of France, has been explored since 1889. From then to 1960, it has yielded substantial material dated to middle “à navettes” Magdalenian developing during the late Pleniglacial. The study of this settlement, although often mentioned, was never dealt with comprehensively until now. Due to its scientific importance for the middle Magdalenian of western Europe, the site is to be reinvestigated through a global interdisciplinary project entitled “The Tardiglacial and the start of Holocene in the Jura and its margins”. This paper will review our present knowledge of the site, radiocarbon dates and archaeological data. It also focuses on ornaments and engraved mobile art.  相似文献   

16.
The Closeau's lower level (Rueil-Malmaison, Hauts-de-Seine) brought evidence of Early Azilian occupations, in which the horse were the main prey. This paper present the zooarchaeological results of the equid's processing, according to the occupation units 4 and 46. The horse acquisition show that chase-approach hunts were the tactic employed, by a single individual or some small bands. The equids hunts' repetition testify that such activities took place at different moments of the year, especially in autumn and at the end of winter-springtime. These data allow a better understanding of the reasons that can explain why all phases of the animal processing were found in the inside of the occupation structures. The consumption of horse's meat and offal seems to take place only partly in situ. The units 4 and 46 can be interpreted as hunting camps, periodically use par Early Azilian bands. Such function of the site may signify that the mobility of these bands could integrated some traits of logistical pattern to a certain extent, but until now their lifeway stay unclear without new discoveries.  相似文献   

17.
The Jungwon region is located in the central part of Korea and it is one of crucial regions for understanding of the Korean Paleolithic culture. Many Paleolithic sites have been discovered in this region, from the lower Paleolithic to the upper Paleolithic. It is of interest the remarkable variety of archeological remains such as human bones, stone tools, animal bones and paleoenvironmental artifacts. As a result, it permits us to reconstruct the subsistence of prehistoric men. This region has an important role for Korean prehistoric researches.  相似文献   

18.
This article focus with recent studies realized on the Vercors Mountain about middle paleolithic site in altitude context. It proposes to make the synthesis of the data concerning the exploitation and especially circulation of the various types of flint inside and near this geographic area. This level of analysis makes it possible to discuss on the mobility degree of the mousterians groups in Vercors and to advance hypotheses on the settlement system within this territory.  相似文献   

19.
During the Miocene time, the Atlas-pelagian block, which is limited northward by the atlasic-alpin chain of North Africa-Sicily, southward by the Gafsa-Jeffara-Azizia fault and eastward by the Malta escarpment, resulted from the extension-compression regime, mainly controlled by the subduction-collision processes. This regime induced the opening of many Miocene microbasins, which have been infilled by silicoclastic materials showing lateral and vertical facies variations and several hiatus associated to tectonic and stratigraphic unconformities. Excepting the very local transgressive regimes, such as those of Langhian and Messinian periods, most of the Miocene deposits took place on internal platforms, especially at the NE part of the country. The fluviodeltaic and alluvial sediments are, in fact, lateral equivalents which infilled the valley and depression enclosed systems towards the SW. In this context (rapid facies variations in time and space, superposition of tectonic and eustatic unconformities, climatic variations, rare or absent stratigraphic markers…), some controversies remain as regards the correlation and dating of these series. This work consists of a study of the lateral and vertical facies and thickness variations, coupled to the identification of the main unconformities. It is also a study of significance of the main sedimentological mechanisms and an inventory of the different palynological and paleontological content of the sediments. The aim of this work is to propose a new vision on the Miocene deposits in Tunisia along a NE-SW axis. Then, using these data, we have correlated the different lithological formations, discuss their age and, finally, proposed paleogeographical drafts for them.  相似文献   

20.
This paper provides an overview of current knowledge of Plio Pleistocene Carnivora from Africa and Europe. In Plio Pleistocene times, many genera extend their ranges in Africa and Eurasia but their evolution are quite distinct in the two continents. In Africa, the modern carnivoran guild of sub saharian Africa originated in the early Pleistocene when took place extinction of archaic species. The north African fossil record is far from complete until the middle Pleistocene. In the middle and late Pleistocene, the modern carnivoran guild is associated with other elements: the simian jackal Canis simensis and two species of ursids Ursus arctos and Ursus deningeri which evolved towards Ursus spelaeus. Western European carnivore faunas show due to migration a constant turn-over of the species. Among felids, Panthera schaubi described by Viret (1954) and attributed to the genus Puma by Hemmer et al. (2004), is morphologically close to the snow leopard Panthera (Uncia) uncia. Canis etruscus is the sister group pf the clade including wolf and coyote and Canis arnensis is close to the African jackals. Ursus deningeri appears in the early Pleistocene together with two arctoid forms Ursus rodei and Ursus dolinensis that may be synonymous to Ursus arctos. The genus Hyaena is present in Europe in the middle and late Pleistocene.  相似文献   

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