共查询到20条相似文献,搜索用时 46 毫秒
1.
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. 相似文献
2.
In a previous note we presented the expression of the late paleolithic spirituality (Welté and Lambert, 2004). A special analytic grid was used as a possible tool for a demonstration. We separeted rationality from metaphysic; notions which are linked with dialectic relations between necessity (daily constraints), thought, action and evolution in the paleolithic period. Starting from the no direct material activities like burials, funeral materials and art, we purpose now that such notions existed before the upper Paleolithic. We infer that a privilegious set of interactions between the animal and the human appeared early in the thought of the people, before the upper Paleolithic. A metaphysic univers forced itself upon them as an evident “anti-world” which is the symmetric shape of the real and tangible world. In such a context, the social system(s) could not discard these duality. 相似文献
3.
We report the case of a 74-year-old patient who presented with cognitive disorders. Morphological imaging showed a tumor which was considered as a meningioma. Surgical resection of this tumor was performed and pathology indicated a meningeal metastasis of a thyroid cancer. The patient had previously a thyroidectomy with an initial benign pathology report. Meningeal metastases of thyroid cancer are rare, and a meningeal metastasis revealing a thyroid cancer is very rare. 相似文献
4.
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
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.
We propose a wide concept in Megalithic Art that includes the decorations in the interior of the monuments, and also the similar graphics detected in the open air, either on rocks, on menhirs and in various spatial contexts (habitational areas, economic areas, funeral areas). The Megalithic Art so understood appears as very similar in all their regional versions. This model can’t be understood as a settling model of some groups above the other. We understand better an interpretation that advocates by the absorptive capacity and the cultural vivacity of all the implied regions. A capillarity model similar as the one, which is applied to the origin of the European producing peoples. The graphics that we analyse here, while deep expression of the symbolic thought, express strong continuity instead of remarkable breaks. 相似文献
7.
An archaeological diagnostic at Falaise revealed a pile of 6 stone rings, isolated from any domestic or burial features. The isolation suggests that the find can be interpreted as a ritual hoard. This hypothesis is possibly confirmed by other aspects: the alternating sizes and raw materials, as well as the site location between two dense early Neolithic settlement zones. The finds probably date to the late Villeneuve-Saint-Germain/Blicquy. The flat, wide rings have traces of manufacture and use. Analysis indicates that they were worn as arm ornaments, at the minimum in pairs. The raw materials, very common in assemblages from north-western France, are of regional origin. Comparable finds in France are rare, limiting interpretation of the hoard. This practice is not frequent and usually involves ring roughouts or worn grindstones, although these technical constraints do not rule out a certain ritualisation. At Falaise, the latter is perceptible but the objects are neither rare nor unusual. For this reason, the phenomenon differs from hoards of axe blades in Danubian cultures of the Rhineland, or of prestige axes at the beginning of the middle Neolithic. 相似文献
8.
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
9.
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
10.
We report a case of multiple brown tumours concerning a 46-year-old, operated for a parathyroid adenoma, who is presenting clinical and biological signs of hyperparathyroidism recurrence. Unusual features in this case were the disseminated distribution of brown tumour and the bone scan pseudo-metastatic aspect. 相似文献
11.
Three major figures from the Vallée des Merveilles have the feet turned inward. The extreme rarity of this posture in the plastic arts of all times and the fact it is attributed essentially to major figures indicate the particular significance of this stand for the authors of the engravings. de Lumley et al. (1995, 2003) interpret this feet position as a hieratic attitude, as the mark the figure belongs to the world of the gods. In this study another hypothesis, which doesn't necessarily exclude the first one, is proposed from an ethological point of view based on the reading of body language made by Wex (1993). She claims that the inward turning of the feet represents a protective reaction to a situation which put the person in a fragile or harmful position. This hypothesis, as well other characteristics, questions the divine or human nature of our three anthropomorphic figures. The shamanistic approach (Hedges, 1993; Whitley, 2001) is raised with respect to this issue and the inward feet position. 相似文献
12.
Prehistoric people have been often lived in the Jungwon region during the Paleolithic. It is a reference for development of the Paleolithic cultures in Korea. During the lower Paleolithic, pebble tool culture has been developed: tools were made with local raw materials and direct percussion and anvil technique were utilized. Debitage and raw material of the middle Paleolithic did not make a great difference to the lower Paleolithic. Otherwise, tool size became small and the number of flake tools increased. The crucial changes occurred during the upper Paleolithic. Technique, acquisition of raw material and tool kits were thoroughly innovated. All of these changes would reveal that the upper Paleolithic people have carried out more various activities, that earlier periods and their social structure would be more complex than other ones'. 相似文献
13.
The Upper Paleolithic of Catalonia has been so far characterized by a very weak presence of artistic representations. This scarcity was especially surprising if we take into account the huge number of discoveries from other zones of the Iberian Peninsula (Valencia, the Cantabrian region). In this paper we present four objects of portable art found at the Molí del Salt site (Vimbodí, Conca de Barberà, Tarragona). Below a mesolithic layer, dated to 8 ka BP, there is an Upper Magdalenian sequence with several dates between 10.8 and 12.5 ka BP. These magdalenian levels have yielded four plaques of schist with engravings, including several animal figurines and one human representations. Once the objects are described, we will place them in the context of the portable art from the Late Upper Paleolithic of Mediterranean Spain. From these data, the chronocultural successions based on the Upper Magdalenian-Microlaminar Epipaleolithic distinction will be discussed. 相似文献
14.
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
15.
Distant metastasis of differentiated thyroid carcinoma generally affect lung and/or bone tissue. Renal metastasis from thyroid carcinoma is extremely rare. We report a case of renal metastasis from a follicular thyroid carcinoma in a 55-year-old man, occuring 11 years after total thyroidectomy, fortuitously discovered on a whole body scan carried out after 131-iodine therapy for neck recurrence of disease. Salient features of our clinical case are the fortuitous mode of discovery the unilateral localization of metastases and especially the long time interval which separates its detection from that of the primitive tumour. This case report exemplifies the useful role of the whole body scan carried out after 131-iodine therapy better adapted to reveal often undetectable occult metastases with low dose, but also to ensure a regular and protracted follow-up of patients treated for differentiated thyroid carcinoma. 相似文献
16.
ObjectiveTo investigate the accuracy in the estimation of the aortic lumen area and distensibility obtained from Steady-State Free-Precession (SSFP) and Phase Contrast (PC) MR sequences. Subjects and methodsSystolic and diastolic aortic lumen of the ascending and descending aorta of 50 subjects, collected with both acquisition sequences, were extracted using a 2D + t automated segmentation method. ResultsWhile the statistical study indicated very similar lumen areas for SSFP and PC data (slope = 1, r = 0.99), the corresponding distensibility values were less correlated ( r = 0.54). Comparison between distensibility values in the ascending and descending aorta and study of these values with aging indicated a greater coherence with expected physiological behavior of the aorta when using SSFP images. DiscussionFlow artifacts were more severe in PC images and could explain the better results obtained when using SSFP sequences. ConclusionA more accurate local assessment of the aortic stiffness is obtained from SSFP image sequences than from PC image sequences. 相似文献
17.
THE reduction of methaemoglobin is one of the few oxidation-reduction reactions known to occur in the mature red blood cell. Approximately 3% of the circulating haemoglobin of an adult man is oxidized each day to methaemoglobin 1 and so a methaemoglobin reduction system is needed in the cell to maintain a low concentration of methaemoglobin (normally less than 1% of the total haemoglobin 2). 相似文献
18.
This paper proposes a new reflection about the late Pleistocene climate impact on the iberomausian coastal expansion. A recent advancement of palaeoenvironment knowledge allows us from now to apprehend a context and circumstances in which are developed diverse late Pleistocene cultures in the Maghreb. This article tries to understand a cultural dynamic of this period by the light of a contemporary climatic evolution. 相似文献
19.
Ground stone tools are lithic tools made on coarse blanks that are not included in the chipped or polished stone studies. During the study of a ground stone tools collection coming from the Campaniform site of Beg ar Loued (Molène island, Finistère, France), the techno-functional unit (TFU) analysis as been adapted to these objects. A TFU is a part of a tool that is technologically independent, having his own part in this tool's overall functioning. The application of this method to ground stone tools needed some adaptations to their characteristics. The aim is to obtain a high level technological analysis for these tools, succeeding to express functional hypothesis. Two concrete examples from Beg ar Loued's collection illustrate the TFU analysis method's application to ground stone tools. This method has the advantage to organize the progress of each piece's analysis. The TFU analysis helps to understand the multifunctional tools by considering each function as a full tool. This allows us to talk about function's hierarchisation and their adaptation to blanks. We also obtain some informations about blank's selection. These many and varied results make the TFU analysis essential for ground stone tool's technological and functional analysis. 相似文献
20.
为研究建立使用微流控芯片技术分离精子与阴道上皮细胞的方法,选用制作工艺简单的玻璃-PDMS芯片,对混合样本进行分离。加样前分别在进、出口池中加入7此和lO此缓冲液,然后在进样口加入2此混合样本。至少静置8nlin后,从出口池中取出3此形成重力驱动的微流体后开始分离,每隔5min在进样口补加1此缓冲液。达到理想分离效果时,用移液器从出口池取出分离出的精子,核酸酶去除游离DNA,经过提取、扩增和电泳分离脸测等步骤得到精子的分型结果。结果显示,使用基于重力驱动微流体原理的微流控芯片可在30min内分离出精子,不会有上皮细胞进入分离通道;通过核酸酶对分离出的精子液的去游DNA处理,可得到单一、完整的精子分型。与传统的差异裂解法相比,这种方法在很大程度上节省了检验时间,在性侵案件中具有一定的法医物证分析价值。 相似文献
|