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期刊的动态性变化及其对应的著录方法
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作者 胡华南 《湖州师范学院学报》 2008年第4期136-140,共5页
期刊是一种连续出版物,在它的发展过程中由于市场需求、同行竞争等诸多因素的影响会导致期刊变化的多样性,即期刊的动态性变化。对于期刊动态性的变化,可以通过不同的著录方法来解决。
关键词 动态性变化 著录方法 期刊变更
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The Content Variations of Main Nutrients in Storage Root Expanding Stages of Sweet Potato and Their Mutual Relationships 被引量:3
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作者 后猛 张允刚 +5 位作者 刘亚菊 王欣 唐维 闫会 马代夫 李强 《Agricultural Science & Technology》 CAS 2015年第11期2481-2484,共4页
[Objective] The content variations of the main nutrients in storage root during expanding stages and their mutual relationships in orange-fleshed sweet pota-to (Ipomoea Batatas(L.) Lam) were studied in this paper.... [Objective] The content variations of the main nutrients in storage root during expanding stages and their mutual relationships in orange-fleshed sweet pota-to (Ipomoea Batatas(L.) Lam) were studied in this paper. [Method] The dynamics of main nutritional ingredients in orange-fleshed sweet potato-variety at 40, 70, 100 and 125 days after transplanting were investigated, and these traits included the 6- carotene content, Fe content, Zn content, starch content, protein content, glucose content, fructose content, and sucrose content. The relationships among these nutri- ents were analyzed during whole developing stage. [Result] B-carotene content in the whole growth period showed straightly increasing firstly, and then decreasing trend, which was unimodal fluctuation curve. The variation tendency of protein con- tent was gently decreasing firstly and then ascending. The dynamics of starch con- tent was similar to l^carotene content, while the fluctuation was stable. The chang- ing curve of carbohydrate was opposite to starch, showing decreasing firstly and then ascending. Fe content was decreasing all the whole developing stage, falling fast and then slowing down. Moreover, Zn content was plummeting. The sucrose content in fresh storage root had significantly negative correlation with β-carotene content, and had positive correlation with fructose content. Starch content had significantly negative correlation with fructose content, and had positive correlation with Zn content. [Conclusion] These research conclusions could guide the variety to har- vest at suitable time, so as to achieve the aim of micronutrition improvement. 展开更多
关键词 Sweet potato Nutritional quality Changing dynamic Correlation
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Effect of Combined Application of Manure and Chemical Fertilizer on the Dynamic Changes of Purple Soil Nutrient and Soil Enzyme Activities
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作者 施娴 袁玲 《Agricultural Science & Technology》 CAS 2011年第5期765-767,775,共4页
[Objective] The aim was to study the effects of combined of manure and fertilizer on the content of nutrients in purplish soil as well as release dynamics of enzyme activities.[Method] The effects of manure and fertil... [Objective] The aim was to study the effects of combined of manure and fertilizer on the content of nutrients in purplish soil as well as release dynamics of enzyme activities.[Method] The effects of manure and fertilizer application on the content of AOM,NH+4-N and NO-3-N in soil as well as release dynamics of enzyme activities were studied by means of simulation culturing.[Result] In the treatments of combined application of simulation culture experiment,the content of active organic matters,NH+4-N,NO-3-N and soil enzyme activities changed dynamically,which showed a shape of inverted "S" with two or more peaks.Compared with the treatment of fertilization,their peaks were relatively flat and occurred relatively late,while the treatment of fertilization had only one but the highest peak.The content of active organic matter came to top around 10 d in the order of cow5fertilizer5pig5fertilizer5cow manurepig manurefertilizer Ⅰfertilizer Ⅱ;the activity of urease came to top around 10 d in all treatments and in the order of pig manurecow5fertilizer5cow manurefertilizer Ⅰfertilizer Ⅱpig5fertilizer5.The activity of saccharase was in the order of pig5fertilizer5pig manurecow5fertilizer5cow manureCKfertilizer Ⅱfertilizer Ⅰ.[Conclusion] The study could provide the theoretical basis for reasonable application of manure and fertilizer. 展开更多
关键词 MANURE Soil nutrients Soil enzyme activities Dynamic changes
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Analysis on the Essential Characters and Biological Yield Change of Purple-fleshed Sweetpotato Xuzishu 3
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作者 唐维 李强 +3 位作者 张允刚 王欣 后猛 马代夫 《Agricultural Science & Technology》 CAS 2014年第10期1660-1666,共7页
Objective] This study was performed to investigate the trait changes and their correlations as wel as the dynamic changes of biological yield of Xuzishu 3, which wil help to enhance the yield and anthocyanin content o... Objective] This study was performed to investigate the trait changes and their correlations as wel as the dynamic changes of biological yield of Xuzishu 3, which wil help to enhance the yield and anthocyanin content of sweetpotato by cul-tivation. [Method] We systematical y measured the agronomic traits, qualitative char-acters and biological yield of Xuzishu 3 during six growing periods to investigate the dynamic changes of its essential characters and yield accumulation. [Result] The characters of Xuzishu 3 appeared most prosperous after the 90th d except for an-thocyanin content. Extremely significant positive correlations were found between ev-ery two of the dry matter rates of above-ground parts (including leaf petioles, leaves and stems), reducing sugar content and potato weight per plant. Assimilated product distributed more in stems and leaves than in storage roots before the 90th d in growing period. Photosynthetic capacity and net assimilation rate gradual y de-creased after the 90th d, but the assimilated product distributing to storage roots in-creased quickly and maximized in the 135th d. [Conclusion] Xuzishu 3 is a late ma-turing variety requiring more fertilizer, and the accumulation of anthocyanin fluctuates during the growth period of Xuzishu 3. So yield of Xuzishu 3 can be increased by applying more fertilizer and extending the growth period reasonably, meanwhile the anthocyanin content can be increased by means of control ing temperature, light, water and phytohormone within 60 d after planting. 展开更多
关键词 Purple-fleshed sweetpotato CHARACTER CORRELATION Biological yield Dynamic change
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Dynamic Changes of Nitrate Reductase Activity within 24 Hours
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作者 杜瑛 王子龙 《Agricultural Science & Technology》 CAS 2012年第11期2284-2286,共3页
[Objective] The research aimed to study the circadian rhythm of nitrate re- ductase activity (NRA) in plant. [Method] The wheat plants at heading stage were used as the materials for the measurement of dynamic chang... [Objective] The research aimed to study the circadian rhythm of nitrate re- ductase activity (NRA) in plant. [Method] The wheat plants at heading stage were used as the materials for the measurement of dynamic changes of nitrate reductase activity (NRA) within 24 h under the conditions of constant high temperature. [Resulti The fluctuation of NRA in wheat changed greatly from 20:00 pm to 11:00 am. The enzyme activity remained constant, but at 14:00 the enzyme activity was the high- est, higher than all the other time points except the enzyme activity measured at11:00. The enzyme activity was the lowest of 17:00, which was lower than all the other time points except the enzyme activity measured at 2:00. [Conclusion] There were autonomous rhythm changes of NRA in wheat in a certain degree. 展开更多
关键词 WHEAT 24 h Nitrate reductase ACTIVITY Solution culture
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Dynamic changes and surveillance function of prion protein expression in gastric cancer drug resistance 被引量:9
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作者 Ji-Heng Wang Jing-Ping Du +5 位作者 Ying-Hai Zhang Xiao-Jun Zhao Ru-Ying Fan Zhi-Hong Wang Zi-Tao Wu Ying Han 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第35期3986-3993,共8页
AIM:To explore the dynamic changes of prion protein (PrPc) in the process of gastric cancer drug resistance and the role of PrPc expression in the prognosis of gastric cancer patients receiving chemotherapy.METHODS:A ... AIM:To explore the dynamic changes of prion protein (PrPc) in the process of gastric cancer drug resistance and the role of PrPc expression in the prognosis of gastric cancer patients receiving chemotherapy.METHODS:A series of gastric cancer cell lines resistant to different concentrations of adriamycin was established,and the expression of PrPc,Bcl-2 and Bax was detected in these cells.Apoptosis was determined using Annexin V staining.Western blotting and immunohisto-chemistry were performed to detect the expression of PrPc in patients receiving chemotherapy and to explore the role of PrPc expression in predicting the chemosensitivity and the outcome of gastric cancer patients receiving chemotherapy.Follow-up was performed for 2 years.RESULTS:PrPc expression was increased with the increase in drug resistance.Bcl-2,together with PrPc,increased the level of anti-apoptosis of cancer cells.Increased PrPc expression predicted the enhanced level of anti-apoptosis and resistance to anticancer drugs.PrPc expression could be used as a marker for predicting the efficacy of chemotherapy and the prognosis of gastric cancer.Increased PrPc expression predicted both poor chemosensitivity and a low 2-year survival rate.Contrarily,low PrPc expression predicted favorable chemosensitivity and a relatively high 2-year survival rate.CONCLUSION:PrPc expression is associated with histological types and differentiation of gastric cancer cells;The PrPc expression level might be a valuable marker in predicting the efficacy of chemotherapy and the prognosis of gastric cancer patients receiving chemotherapy. 展开更多
关键词 Prion protein Gastric cancer Drug resistance CHEMOTHERAPY APOPTOSIS
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The Influence of Seasonal Snow on Soil Thermal and Water Dynamics under Different Vegetation Covers in a Permafrost Region 被引量:8
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作者 HANG Juan WANG Gen-xu +1 位作者 GAO Yong-heng WANG Yi-bo 《Journal of Mountain Science》 SCIE CSCD 2014年第3期727-745,共19页
Seasonal snow is one of the most important influences on the development and distribution of permafrost and the hydrothermal regime in surface soil. Alpine meadow, which constitutes the main land type in permafrost re... Seasonal snow is one of the most important influences on the development and distribution of permafrost and the hydrothermal regime in surface soil. Alpine meadow, which constitutes the main land type in permafrost regions of the Qinghai-Tibet Plateau, was selected to study the influence of seasonal snow on the temperature and moisture in active soil layers under different vegetation coverage. Monitoring sites for soil moisture and temperature were constructed to observe the hydrothermal processes in active soil layers under different vegetation cover with seasonal snow cover variation for three years from 2010 to 2012. Differences in soil temperature and moisture in areas of diverse vegetation coverage with varying levels of snow cover were analyzed using active soil layer water and temperature indices. The results indicated that snow cover greatly influenced the hydrothermal dynamics of the active soil layer in alpine meadows. In the snow manipulation experiment with a snow depth greater than 15 cm, the snow cover postponed both the freeze-fall and thawrise onset times of soil temperature and moisture in alpine LC(lower vegetation coverage) meadows and of soil moisture in alpine HC(higher vegetation coverage) meadows; however, the opposite response occurred for soil temperatures of alpine HC meadows,where the entire melting period was extended by advancing the thaw-rise and delaying the freeze-fall onset time of the soil temperature. Snow cover resulted in a decreased amplitude and rate of variation in soil temperature, for both alpine HC meadows and alpine LC meadows, whereas the distinct influence of snow cover on the amplitude and rate of soil moisture variation occurred at different soil layers with different vegetation coverages. Snow cover increased the soil moisture of alpine grasslands during thawing periods. The results confirmed that the annual hydrothermal dynamics of active layers in permafrost were subject to the synergistic actions of both snow cover and vegetation coverage. 展开更多
关键词 PERMAFROST Snow cover Vegetationcover Active soil layer Hydrothermal dynamics Synergistic action
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Environmental Factors Affecting Temporal and Spatial Dynamics of Soil Erosion in Xingguo County, South China 被引量:12
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作者 WANG Ku SHI Xue-Zheng +5 位作者 YU Dong-Sheng SHI De-Ming CHEN Jing-Ming XU Bin-Bin LIANG Yin LI De-Cheng 《Pedosphere》 SCIE CAS CSCD 2005年第5期620-627,共8页
By using soil erosion maps of four different time periods and a digital elevation model (DEM), in combination withthe remote sensing and GIS technologies, soil erosion dynamics in Xingguo County of Jiangxi Province in... By using soil erosion maps of four different time periods and a digital elevation model (DEM), in combination withthe remote sensing and GIS technologies, soil erosion dynamics in Xingguo County of Jiangxi Province in South Chinawere analyzed on both temporal and spatial scales in soils of different parent materials, altitudes and slopes. The resultsshowed that from 1958 to 2000 severe soil erosion was coming under control with a decreasing percentage of the land undersevere erosion. It was also found that the soils developed from Quaternary red clay, granite and purple shale were moresusceptible to soil erosion and that areas sitting between 200 to 500 m in altitude with a slope less than 3° or between7° to 20° where human activities were frequent remained to be zones where soil erosion was most likely to occur. Theseareas deserve special attention in monitoring and controlling. 展开更多
关键词 GIS remote sensing soil erosion South China Xingguo County
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Three-Step Damage Identification Method Based on Dynamic Characteristics
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作者 孙国帅 柳春光 +1 位作者 张士博 郝二通 《Transactions of Tianjin University》 EI CAS 2014年第5期379-384,共6页
A three-step damage identification method based on dynamic characteristics is proposed to improve the structure reliability and security and avoid serious accident. In the proposed method, the frequency and difference... A three-step damage identification method based on dynamic characteristics is proposed to improve the structure reliability and security and avoid serious accident. In the proposed method, the frequency and difference of modal curvature(DMC) are used as damage indexes. Firstly, the detection of the occurrence of damage is addressed by the frequency or the square of frequency change. Then the damage location inside the structure is measured by the DMC. Finally, with the stiffness reduction rate as a damage factor, the amount of damage is estimated by the optimization algorithm. The three-step damage identification method has been validated by conducting the simulation on a cantilever beam and the shaking table test on a submerged bridge. The results show that the method proposed in this paper can effectively solve the damage identification problem in theory and engineering practice. 展开更多
关键词 damage identification dynamic characteristics FREQUENCY difference of modal curvature optimization algorithm shaking table test
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Effects of Bearing Type on Seismic Response of Small Base Isolation System Using Friction Bearings
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作者 Katsumi Kurita Mikito Kezuka +3 位作者 Shigeru Aoki Yuuj i Nakanishi Kazutoshi Tominaga Mitsuo Kanazawa 《Journal of Civil Engineering and Architecture》 2014年第3期261-267,共7页
In this study, dynamic characteristics of the small base isolation system using new friction bearings are investigated by excitation experiment, and compared to other one using previous bearings. Peak amplitude of the... In this study, dynamic characteristics of the small base isolation system using new friction bearings are investigated by excitation experiment, and compared to other one using previous bearings. Peak amplitude of the acceleration response waves on the small base isolation system is decreased to about 10%-25% compared to the input waves. Also root mean square amplitude is decreased to about 10%-40%. In case of the ball embedded a cylindrical sponge, the new bearing, the damping ratio increases with increasing width of the cylindrical sponge. The natural frequency does not change. On the other hand, in case of the marble plate that is previous bearing, the damping ratio increases with increasing curvature radius of the marble plate, the natural frequency also increases. Therefore, the small base isolation system using new friction bearing provides better performance. The responses of the base isolation system indicate nonlinier effects by friction force. 展开更多
关键词 Small base isolation system friction bearing peak amplitude natural frequency damping ratio.
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Consistent Distribution of Stress before Strong Earthquake from Focal Mechanisms
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作者 Zeren Zhima Diao Guiling Li Zhixiong 《Earthquake Research in China》 2010年第4期415-422,共8页
At some stage of a strong earthquake preparation, the focal mechanisms of small earthquakes have roughly the same direction with the tectonic stress field. According to this feature, we define the angle between P, B a... At some stage of a strong earthquake preparation, the focal mechanisms of small earthquakes have roughly the same direction with the tectonic stress field. According to this feature, we define the angle between P, B and T axis of focal mechanisms and the three stress axes of tectonic stress field as the consistency parameter a in studying the dynamic changes of stress fields in earthquake preparation areas. We mainly analyze the changes of the consistency parameter a of the Mw8. 3 Knril island arc earthquake and the Mw8. 4 Peru earthquake. Our study shows that before the strong earthquakes, the earthquake area saw a low consistency, and the focal mechanisms of a series of small earthquakes had small differences in the directions with the tectonic stress field, which means the foreshocks were under the control of the stress field. On the other hand, a higher consistency means the focal mechanisms of their aftershocks are scattered and have big differences in the directions with the tectonic field, which indicate that the control of background stress field starts weakening. 展开更多
关键词 Focal mechanisms The consistency Kuril Island Peru Stress field
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Dynamic change of xylanase activity and gene expression during wheat germination on As(III) stress
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作者 LI Chun-xi LI Dan-dan SHAO Yun FENG Shu-li ZHANG Dai-jing ZHANG Bei-bei JIANG Li-na 《Journal of Life Sciences》 2008年第5期45-50,共6页
Through water cultivating method, the dynamic changes of xylanase activity in seed, root and plumule of wheat with different As (III) concentration treatment were studied. The results indicated that the order of ave... Through water cultivating method, the dynamic changes of xylanase activity in seed, root and plumule of wheat with different As (III) concentration treatment were studied. The results indicated that the order of average xylanase activity was seed〉plumule〉root. With the increasing concentration of As (III), the xylanase activity elevated first then dropped in seed, but it descended first then ascended in root and plumule. As the sampling time prolonged, the xylanase activity of seeds climbed first then dropped on the four as (III) concentration, the same trend also appeared in pulume, as the as (Ill) concentration went up, the xylanase activity moved up simultaneity. Semi-quantity Reverse Transcription Polymerase Chain Reaction was used in the study, the results indicated that, the xylanase gene began to express at 132 h on 0 mg/L As (III) concentration and at 120h on other concentration in the leaves of wheat. 展开更多
关键词 As(III) stress wheat xylanase xylanase gene actingene semi-quantity reverse transcription polymerase chainreaction
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An Opinion Mining Task in Turkish Language: A Model for Assigning Opinions in Turkish Blogs to the Polarities
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作者 Cigdem Aytekin 《Journalism and Mass Communication》 2013年第3期179-198,共20页
Global changes took place at a neck-breaking speed in lots of fields along with the Web 2.0 era, which can be stated as the new Internet trend. Web pages which once were a statical structure that can be said to become... Global changes took place at a neck-breaking speed in lots of fields along with the Web 2.0 era, which can be stated as the new Internet trend. Web pages which once were a statical structure that can be said to become dynamic pages created by users, and in this regard they can be said to have been democratized by evolving. Social media, which were structured alongside with this era, by providing a large data flow for businesses, present new and improvable opportunities in the field of creating effective strategies. There are lots of blogs in today's Internet environment which includes customer ideas regarding the products/services that they possess. This environment, which in a way globalizes the customer ideas, is a new medium suitable for examination in terms of its increasing the business-customer interaction and due to its transporter nature; it provides the text data that may be analyzed in the field of Customer Relationship Management to businesses. Thus, businesses should follow blog environments to see how the product/service they provide is greeted in terms of the customer focus and it should be seen as an important job on which they can conduct effective analyses. For this purpose, a model proposal that will assign the ideas to the Turkish blogs was given in the study. Opinion mining methods were used in the model, and so to perceive a general look-on about products/services, a methodology was devised, which will assign the text based opinion data on the Turkish blogs to the poles. Success of the pole assignment of the model is evaluated with the precision measure. 展开更多
关键词 opinion mining text classification sentiment classification semantic orientation positive/negative polarity
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Effect of Ultraviolet Aging on Asphalt Rheological Properties
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作者 Wang Jiani Xue Zhongjun +1 位作者 Tan Yiqiu Zhang Lei 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2013年第4期26-32,共7页
This paper simulated the ultraviolet aging process of asphalt and used dynamic mechanic analysis (DMA) method to evaluate the effect of ultraviolet aging on the asphalt theological properties. After having experienc... This paper simulated the ultraviolet aging process of asphalt and used dynamic mechanic analysis (DMA) method to evaluate the effect of ultraviolet aging on the asphalt theological properties. After having experienced ultravio- let aging, the low temperature performance of asphalt binder decreased significantly, with its complex modulus increased and phase angle decreased along with changing rheological properties as compared to the performance of original asphalt binder. The ultraviolet aging process would make asphalt binder more sensitive to brittle and fatigue failure. On the basis of the time-temperature superposition principle (TTSP), the viscoelastic transition frequency (coT) is proposed to evaluate the effect of ultraviolet aging. It is found that with the increase in ultraviolet aging time, the cox moves to the lower frequency range gradually. Since the viscoelastic transition frequency is sensitive to the effect of aging, it can be used as an indicator of ultraviolet aging. 展开更多
关键词 ASPHALT ultraviolet aging rheological properties viscoelastic transition frequency
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论自然环境变化的记述和意义——以第二轮《铅山县志》为例
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作者 郑冬香 曾健雄 《中国地方志》 2015年第7期17-20,共4页
志书对自然环境的记述,应该充分认识自然环境自身发展规律,了解地貌、气候、水文、土壤、植被等各要素的关系,记述好动态性交化。自然环境记述要遵循动态性、等级性、整体性原则,记述方法多种多样,可根据自然环境变化关系选择递进、转... 志书对自然环境的记述,应该充分认识自然环境自身发展规律,了解地貌、气候、水文、土壤、植被等各要素的关系,记述好动态性交化。自然环境记述要遵循动态性、等级性、整体性原则,记述方法多种多样,可根据自然环境变化关系选择递进、转折、平列、顺延等记述方法,充分发挥志书记述自然环境的作用。 展开更多
关键词 自然环境 动态性变化 《铅山县志》
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服务外包伙伴关系治理匹配机制研究 被引量:3
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作者 苏娜 刘东 《上海经济研究》 CSSCI 北大核心 2018年第2期117-128,共12页
近些年来,随着服务外包项目从ITO向BPO、KPO转型升级,外包的动机已经从最初的降低交易成本转向战略合作,双方之间伙伴关系管理的成败对双方企业的绩效和持续竞争优势的发挥起着关键作用。该文正是基于对服务外包伙伴关系动态性变化的认... 近些年来,随着服务外包项目从ITO向BPO、KPO转型升级,外包的动机已经从最初的降低交易成本转向战略合作,双方之间伙伴关系管理的成败对双方企业的绩效和持续竞争优势的发挥起着关键作用。该文正是基于对服务外包伙伴关系动态性变化的认识,找寻并设计匹配的治理机制,为企业制定相应的决策。研究发现:以支持型为代表的短期伙伴关系匹配于较完善的正式契约治理,以依赖型和结盟型为代表的中期伙伴关系匹配于有一定弹性的关系契约治理,而以联盟型为代表的长期伙伴关系则匹配于心理契约和超市场契约治理。 展开更多
关键词 服务外包 伙伴关系 治理机制 动态性变化 匹配机制
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Delimiting Ecological Space and Simulating Spatial-temporal Changes in Its Ecosystem Service Functions based on a Dynamic Perspective: A Case Study on Qionglai City of Sichuan Province, China 被引量:1
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作者 OU Dinghua WU Nengjun +6 位作者 LI Yuanxi MA Qing ZHENG Siyuan LI Shiqi YU Dongrui TANG Haolun GAO Xuesong 《Journal of Resources and Ecology》 CSCD 2022年第6期1128-1142,共15页
Delimiting ecological space scientifically and making reasonable predictions of the spatial-temporal trend of changes in the dominant ecosystem service functions(ESFs) are the basis of constructing an ecological prote... Delimiting ecological space scientifically and making reasonable predictions of the spatial-temporal trend of changes in the dominant ecosystem service functions(ESFs) are the basis of constructing an ecological protection pattern of territorial space, which has important theoretical significance and application value. At present, most research on the identification, functional partitioning and pattern reconstruction of ecological space refers to the current ESFs and their structural information, which ignores the spatial-temporal dynamic nature of the comprehensive and dominant ESFs, and does not seriously consider the change simulation in the dominant ESFs of the future ecological space. This affects the rationality of constructing an ecological space protection pattern to some extent. In this study, we propose an ecological space delimitation method based on the dynamic change characteristics of the ESFs, realize the identification of the ecological space range in Qionglai City and solve the problem of ignoring the spatial-temporal changes of ESFs in current research. On this basis, we also apply the Markov-CA model to integrate the spatial-temporal change characteristics of the dominant ESFs, successfully realize the simulation of the spatial-temporal changes in the dominant ESFs in Qionglai City’s ecological space in 2025, find a suitable method for simulating ecological spatial-temporal changes and also provide a basis for constructing a reasonable ecological space protection pattern. This study finds that the comprehensive quantity of ESF and its annual rate of change in Qionglai City show obvious dynamics, which confirms the necessity of considering the dynamic characteristics of ESFs when identifying ecological space. The areas of ecological space in Qionglai city represent 98307 ha by using the ecological space identification method proposed in this study, which is consistent with the ecological spatial distribution in the local ecological civilization construction plan. This confirms the reliability of the ecological space identification method based on the dynamic characteristics of the ESFs. The results also show that the dominant ESFs in Qionglai City represented strong non-stationary characteristics during 2003–2019,which showed that we should fully consider the influence of the dynamics in the dominant ESFs on the future ESF pattern during the process of constructing the ecological spatial protection pattern. The Markov-CA model realized the simulation of spatial-temporal changes in the dominant ESFs with a high precision Kappa coefficient of above 0.95, which illustrated the feasibility of using this model to simulate the future dominant ESF spatial pattern. The simulation results showed that the dominant ESFs in Qionglai will still undergo mutual conversions during 2019–2025 due to the effect of the their non-stationary nature. The ecological space will still maintain the three dominant ESFs of primary product production, climate regulation and hydrological regulation in 2025, but their areas will change to 32793 ha, 52490 ha and 13024 ha, respectively. This study can serve as a scientific reference for the delimitation of the ecological conservation redline, ecological function regionalization and the construction of an ecological spatial protection pattern. 展开更多
关键词 ecological space dominant ecosystem service functions(ESFs) dynamicity spatial-temporal change simulation Markov-CA model
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The Bargmann Symmetry Constraint and Binary Nonlinearization of the Super Dirac Systems 被引量:7
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作者 Jing YU Jingsong HE +1 位作者 Wenxiu MA Yi CHENG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2010年第3期361-372,共12页
An explicit Bargmann symmetry constraint is computed and its associated binary nonlinearization of Lax pairs is carried out for the super Dirac systems. Under the obtained symmetry constraint, the n-th flow of the sup... An explicit Bargmann symmetry constraint is computed and its associated binary nonlinearization of Lax pairs is carried out for the super Dirac systems. Under the obtained symmetry constraint, the n-th flow of the super Dirac hierarchy is decomposed into two super finite-diinensional integrable Hamiltonian systems, defined over the super- symmetry manifold R^4N{2N with the corresponding dynamical variables x and tn. The integrals of motion required for Liouville integrability are explicitly given. 展开更多
关键词 Symmetry constraints Binary nonlinearization Super Dirac systems Super finite-dimensional integrable Hamiltonian systems
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Changes in Soil Organic Carbon Dynamics in a Native C4 Plant-Dominated Tidal Marsh Following Spartina alterniflora Invasion 被引量:10
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作者 jin baoshi lai derrick yuk fo +2 位作者 gao dengzhou tong chuan zeng congsheng 《Pedosphere》 SCIE CAS CSCD 2017年第5期856-867,共12页
Invasion of an exotic C4 plant Spartina alterniflora has been shown to increase soil organic carbon (SOC) concentrations in native C3 plant-dominated coastal wetlands of China. However, little is known about the eff... Invasion of an exotic C4 plant Spartina alterniflora has been shown to increase soil organic carbon (SOC) concentrations in native C3 plant-dominated coastal wetlands of China. However, little is known about the effects of S. alterniflora invasion on SOC concentrations and fractions in tidal marshes dominated by native C4 plants. In this study, a field experiment was conducted in a tidal marsh dominated by the native C4 plant Cyperus malaccensis in the Minjiang River estuary, China. Concentrations of SOC and liable SOC fractions, dissolved organic carbon (DOG), microbial biomass carbon (MBC), and easily oxidizable carbon (EOC), were measured in the top 50-cm soils of the C. malaccensis community, as well as those of three S. alterniflova communities with an invasion duration of 0-4 years (SA-4), 4-8 years (SA-8), and 8-12 years (SA-12), respectively. Results showed that both SOC stocks in the 50-cm soils and mean SOC concentrations in the surface soils (0-10 cm) of the C. malaccensis community increased with the duration of S. alterniflora invasion, whereas SOC concentrations in the 10-50-cm soils decreased slightly during the initial period of S. alterniflora invasion, before increasing again. The pattern of changes in labile SOC fractions (DOC, MBC, and EOC) with invasion duration was generally similar to that of SOC, while the ratios of labile SOC fractions to total SOC (DOC:SOC, MBC:SOC, and EOC:SOC) decreased significantly with the duration of S. alterniflora invasion. The findings of this study suggest that invasion of the exotic C4 plant S. alternifora into a marsh dominated by the native C4 plant C. malaecensis would enhance SOC sequestration owing to the greater amount of biomass and lower proportion of labile SOC fractions present in the S. alterniflora communities. 展开更多
关键词 carbon sequestration carbon stock coastal wetland labile organic carbon fractions plant invasion redundancy analyses river estuary
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L_1 adaptive controller design for hypersonic formation flight 被引量:5
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作者 CHEN Qi WAN Jing AI JianLiang 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第10期1597-1608,共12页
The design of an L_1 adaptive controller for hypersonic formation flight is presented. The traditional leader/wingman formation control problem is considered, with focused attention on dealing with the input disturban... The design of an L_1 adaptive controller for hypersonic formation flight is presented. The traditional leader/wingman formation control problem is considered, with focused attention on dealing with the input disturbance and parametric variations, both of which are intrinsic properties of the system that result in undesired control performance. A proportional-derivative control scheme based on nonlinear dynamic inversion is implemented as the baseline controller, and an L_1 adaptive controller is augmented to the baseline controller to attenuate the effects of input disturbance and parametric variations. Simulation results illustrate the effectiveness of the proposed control scheme. 展开更多
关键词 hypersonic flight control nonlinear dynamic inversion L1 adaptive control input disturbance parametric variation
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