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Zhang X.,National Library of China | Shi Y.,HIGH-TECH | Liu W.,Beijing University of Technology
Fenmo Yejin Jishu/Powder Metallurgy Technology | Year: 2013

Gelcasting-process have unique advantages such as suitability for complex molding of various powders, uniform density, fewer defects, high strength, no need for specialized degreasing step, low mold cost etc. The principle and process of gelcasting-process were briefly introduced. Basing on research works on the new non-water-based gelcasting system suitable for metal powders, application examples of the metal materials and products prepared by non-water-based gelcasting using the alloy powders were introduced as well.

Han Q.Y.,State Key Laboratory of Geomechanics and Deep Underground Engineering | Peng X.,China Institute of Technology | Yang Y.P.,National Library of China
Advanced Materials Research | Year: 2014

Scaling and corrosion are the two problems of the cooling system. In this paper, the influence of emulsion on the corrosion and scaling on pipelines of cooling system deep coal mine is studied by the experiment. Firstly, the characteristics of water consist in the pipe of cooling system are received; secondly, 12 kinds of emulsion were prepared in the experiment and characteristics of the water mixed with emulsion are tested; Finally, we calculated the IS, IR at the cases of different temperatures and put forward the mass fraction of emulsion which can prevent the scaling and corrosion. The results are as follows.1) When the water temperature is higher than 37°C, there will be no corrosion and scaling when no joins of emulsion.2) When the water temperature is 27~37°C, the pipeline surface will be little corroded by the mining water, and the joining of emulsion with the mass fraction of 1~2% can prevent scaling and corrosion.3) When the water temperature is higher than 27°C, the pipeline surface will be corroded by the mining water, and the joining of emulsion with the mass fraction of 3~4% can prevent scaling and corrosion. The research is of great importance to the cooling under deep coal mine, at the same time to the scale inhibition and anticorrosion on the geothermal engineering. © (2014) Trans Tech Publications, Switzerland.

Chen T.,Taiyuan University of Technology | Chen T.,University of Chinese Academy of Sciences | Wang X.,Xinjiang Institute of Ecology and Geography | Dai J.,National Library of China | And 2 more authors.
Quaternary International | Year: 2016

The Yingpan cemetery is situated in the Lop Nor region of the Tarim Basin in southern Xinjiang, China, and it has been dated to the Eastern Han and Jin dynasties (∼25-420 AD). Macrofossil and microfossil analyses were undertaken to investigate the associated plant and food remains. The results indicated that the principal cereal crops of Yingpan people were . Panicum miliaceum, . Triticum aestivum, and . Hordeum vulgare var. . coeleste, moreover flour of . Triticum aestivum was also processed into cakes. Meanwhile, plant remains of . Vitis vinifera suggested grape cultivation and utilization in this region. Apart from the agricultural and horticultural remains, two taxa of wild plants were also identified. This study presents the first systematic archaeobotanical data about the cereal cultivation and plant utilization in ancient Xinjiang during the Eastern Han and Jin dynasties in the Tarim Basin. © 2016 Elsevier Ltd and INQUA.

Qin X.-G.,CAS Institute of Geology and Geophysics | Ning B.,National Library of China | Yin Z.-Q.,China Institute of Geo nvironment Monitoring | Mu Y.,CAS Institute of Geology and Geophysics
Diqiu Kexue - Zhongguo Dizhi Daxue Xuebao/Earth Science - Journal of China University of Geosciences | Year: 2011

Glacial-interglacial change in terrestrial carbon pools is an unknown issue in paleo-carbon cycle research. Carbon flux between carbon pools in different time scales has been studied from marine isotope, model simulating and paleo-environmental evidence by many scientists. Any tiny fluctuation of soil carbon pool with vast carbon reserves would affect ecosystem more easily than other terrestrial carbon pools and atmospheric CO2 concentration, and in turn impacted global climate finally. In this paper, the evolution of carbon density of soil organic matter (SOCD) in south of Chinese loess plateau over the past 40 ka was studied. It was found that SOCD in MIS-3 was more intensive than magnetic susceptibility in the details to explain tiny fluctuations. SOCD increased rapidly and fluctuated several times in high level in MIS-3. It may be because climate in this period was more suitable for soil organic carbon's accumulation and preservation in loess and paleosoil. In the last glacial maximum (LGM), SOCD decreased sharply as climate rapidly fluctuated. During the period, there was a climatic and SOCD rebounding event that lasted for about 2 ka and the minimum SOCD value occurred at ~14 ka BP and ~19 ka BP. Compared with the marine oxygen isotope, the trends of soil organic carbon pool in LGM and Holocene were similar. The magnetic susceptibility began to increase at 15 ka, and the increase seemed to be prior to SOCD and marine oxygen isotope. At the early time of Holocene, SOCD increased gradually and then decreased, and the maximum was at about 7-5 ka BP.

Zou Q.,Beijing Jiaotong University | Luo S.,Beijing Jiaotong University | Zhong J.,National Library of China | Yang L.,Beijing Jiaotong University
Journal of Electronic Imaging | Year: 2013

Abstract. Here, we propose a confidence shape metric for level set segmentation. First, the confidence shape metric, which encodes local confidence into the matching result, is used in matching shapes and producing confidence maps. Then, based on the confidence shape prior, the level set function evolves to a desired contour. The proposed shape metric allows representation of shape variations beyond the coverage of training shapes under the level set framework, which is suitable for segmenting strongly deformed and cluttered images, especially when the set of training shapes is sparse compared with numerous intracategory variations. We evaluated the proposed approach on the challenging Weizmann dataset and computed tomography images. Experimental results indicate the advantage of confidence shape prior over shape prior without confidence under the Dice-coefficient metric. © 2013 SPIE and IS&T.

Wei Z.,National Library of China | Lirong S.,National Library of China | Chunming L.,National Library of China
Electronic Library | Year: 2012

Purpose - Disabled people are often disadvantaged groups with varying special needs. Therefore, acquiring knowledge, improving information literacy, and participating in social activities becomes a survival and development problem for many disabled people. As an information dissemination centre, libraries should assume the responsibilities and obligations of providing knowledge aids for the disabled. This paper aims to introduce the China Digital Library for Visual Impairment website, which provides knowledge services for people with visual impairment, and to describe and discuss its background, its construction, initial achievements, and future prospects. Design/methodology/ approach - The paper adopts a case study analysis method, which takes the website of China Digital Library for Visual Impairment (CDLVI) as an example, introducing its resources development, service manners, developing mechanism. Findings - Based on the experiences of China Digital Library for Visual Impairment (CDLVI), the NLC will construct a perfect reading service system and knowledge network for the disabled, which provides personalized and convenient services, and creates good learning conditions for the whole special group of people with disabilities. Originality/value - The paper provides an introduction to the CDLVI website, which provides services for people with visual impairment. © Copyright - 2012 Emerald Group Publishing Limited. All rights reserved.

Sun Q.-Z.,Chinese Academy of Agricultural Sciences | Liu Q.,Institute of Animal and Veterinary science of Liangshan Prefecture | Na Y.,National Library of China | Li F.,Chinese Academy of Agricultural Sciences | Tao Y.,Chinese Academy of Agricultural Sciences
Acta Prataculturae Sinica | Year: 2016

This paper applies the principles of textual analysis to a collection of historical literatures and a summary of modern research findings in order to investigate the various interpretations of who is responsible for introducing alfalfa to China during the Han dynasty. There are four characteristic views of alfalfa's introduction from Western Regions in the historical, agricultural and pratacultural fields. Claims have been made that those responsible were envoys of the Han dynasty, or Zhang Qian, or the Ershi General Li Guangli, while others claim it remains uncertain. Our investigation shows that the first view is closest to the historical facts. The second view is popular and accepted by most scholars but it lacks the support of historical data. The third view has not been widely accepted at present. Thus the claims that alfalfa was introduced by either Zhang Qian or Li Guangli need further verification by exploring the available historical data. Copyright © ACTA PRATACULTURAE SINICA.

Wang X.,Shijiazhuang Railway Institute | Chen Y.,Shijiazhuang Railway Institute | Zhang L.,National Library of China
Journal of Industrial Engineering and Management | Year: 2013

Purpose: The modern logistics has a significant role in today's society, logistics cost accounts for 35% to 50% of the total logistics costs, so it has great significance to improve the transport performance of logistics enterprises. Design/methodology/approach: The authors selected the transportation performance evaluation index of logistics enterprise, with the aid of the fuzzy theory and analytic hierarchy process (AHP), adopted the combining method of quantitative and qualitative analysis, constructed the transport performance evaluation system of logistics enterprises. Findings: Through the model analysis, we know that the choice of logistics enterprises transportation performance evaluation index system is in the condition of relatively high, which has certain guiding significance to improve transport efficiency and reduce transportation cost for the logistics enterprise. Research limitations/implications: It has great significance to improve the transport performance of the logistics enterprises. But because of the experts' subjective factors, the selected indicators of the text can not accurately quantify. Practical implications: It has important practical significance to promote the development of modern logistics enterprises and save the social cost. Originality/value: Current research methods of transport performance mainly include the PDCA cycle model, key performance indicators (KPI), principal component analysis method and etc. The authors adopted the combining method of the fuzzy theory and analytic hierarchy process (AHP) research on transport performance problems.

Shuping L.,National Library of China | Quan W.,Digital Library Promotion Project
Preservation, Digital Technology and Culture | Year: 2014

This paper describes the development of the Digital Library Promotion Project (DLPP) at the National Library of China and the ways in which it has enhanced the access to cultural heritage. In May 2011, China launched the DLPP as one of a series of digital library initiatives which have been developed in recent years. By building an interconnected and distributed digital library platform and resource clusters, and providing digital cultural services in a variety of media, the DLPP enhances public library services in China. The authors found that digital projects such as the DLPP enrich social discourse and increase access to China's cultural heritage.

Cao J.,Communication University of China | Shi M.,Communication University of China | Wu B.,National Library of China
3rd International Joint Conference on Computational Sciences and Optimization, CSO 2010: Theoretical Development and Engineering Practice | Year: 2010

In this paper we consider the total bondage number b t(G) for Generalized Petersen graphs, which is defined as the minimum number of edges whose removal results in a new graph with larger total domination number. This parameter measures to some extent the robustness of an interconnection network with respect to link failures. Generalized Petersen graphs are an important class of commonly used interconnection networks and have been studied recently. By constructing a family of minimum total dominating sets we compute the total bondage number of the Generalized Petersen graphs. © 2010 IEEE.

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