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Better use of experience from other reservoirs for accurate production forecasting by learn-to-learn method
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作者 Hao-Chen Wang Kai Zhang +7 位作者 Nancy Chen Wen-Sheng Zhou Chen Liu Ji-Fu Wang Li-Ming Zhang Zhi-Gang Yu Shi-Ti Cui Mei-Chun Yang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期716-728,共13页
To assess whether a development strategy will be profitable enough,production forecasting is a crucial and difficult step in the process.The development history of other reservoirs in the same class tends to be studie... To assess whether a development strategy will be profitable enough,production forecasting is a crucial and difficult step in the process.The development history of other reservoirs in the same class tends to be studied to make predictions accurate.However,the permeability field,well patterns,and development regime must all be similar for two reservoirs to be considered in the same class.This results in very few available experiences from other reservoirs even though there is a lot of historical information on numerous reservoirs because it is difficult to find such similar reservoirs.This paper proposes a learn-to-learn method,which can better utilize a vast amount of historical data from various reservoirs.Intuitively,the proposed method first learns how to learn samples before directly learning rules in samples.Technically,by utilizing gradients from networks with independent parameters and copied structure in each class of reservoirs,the proposed network obtains the optimal shared initial parameters which are regarded as transferable information across different classes.Based on that,the network is able to predict future production indices for the target reservoir by only training with very limited samples collected from reservoirs in the same class.Two cases further demonstrate its superiority in accuracy to other widely-used network methods. 展开更多
关键词 production forecasting Multiple patterns Few-shot learning Transfer learning
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Effect of perforation density distribution on production of perforated horizontal wellbore
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作者 KAREEM Hasanain J. HASINI Hasril ABDULWAHID Mohammed A. 《Petroleum Exploration and Development》 SCIE 2024年第2期464-475,共12页
To address the issue of horizontal well production affected by the distribution of perforation density in the wellbore,a numerical model for simulating two-phase flow in a horizontal well is established under two perf... To address the issue of horizontal well production affected by the distribution of perforation density in the wellbore,a numerical model for simulating two-phase flow in a horizontal well is established under two perforation density distribution conditions(i.e.increasing the perforation density at inlet and outlet sections respectively).The simulation results are compared with experimental results to verify the reliability of the numerical simulation method.The behaviors of the total pressure drop,superficial velocity of air-water two-phase flow,void fraction,liquid film thickness,air production and liquid production that occur with various flow patterns are investigated under two perforation density distribution conditions based on the numerical model.The total pressure drop,superficial velocity of the mixture and void fraction increase with the air flow rate when the water flow rate is constant.The liquid film thickness decreases when the air flow rate increases.The liquid and air productions increase when the perforation density increases at the inlet section compared with increasing the perforation density at the outlet section of the perforated horizontal wellbore.It is noted that the air production increases with the air flow rate.Liquid production increases with the bubble flow and begins to decrease at the transition point of the slug-stratified flow,then increases through the stratified wave flow.The normalized liquid flux is higher when the perforation density increases at the inlet section,and increases with the radial air flow rate. 展开更多
关键词 horizontal wellbore two-phase flow pattern perforation density wellbore pressure drop void fraction production performance
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An Analysis of Innovative Contributions to the Important Discourse on the Development of New Quality Productivity
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作者 Yao Hao Jie Wu 《Journal of Contemporary Educational Research》 2024年第6期135-141,共7页
The discourse on developing high-quality productivity marks a significant theoretical innovation,which is conducive to the modernization and sinicization of Marxism.It refines our understanding of“new quality product... The discourse on developing high-quality productivity marks a significant theoretical innovation,which is conducive to the modernization and sinicization of Marxism.It refines our understanding of“new quality productivity,”defining it as an advanced form driven by innovation,embodying“high technology,efficiency,and quality,”with the aim of comprehensively enhancing productivity.It elucidates the necessity of cultivating such forces,asserting that they are crucial for achieving high-quality development,securing a leading position in global technology,and fulfilling the aspirations for a better life.Moreover,it outlines a new implementation route,emphasizing strategies such as fostering technological autonomy,nurturing emerging industries,integrating education and talent in technology,adopting a“build through challenges”approach,adjusting solutions locally,and providing categorized guidance,all of which are based on the ongoing comprehensive reforms. 展开更多
关键词 New quality productivity Basic connotation Important discourse Realistic approach Innovative contributions
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Semi-tensor product approach to controllability and stabilizability of finite automata 被引量:12
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作者 Yongyi Yan Zengqiang Chen Zhongxin Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第1期134-141,共8页
Using semi-tensor product of matrices, the controllability and stabilizability of finite automata are investigated. By expressing the states, inputs, and outputs in vector forms, the transition and output functions ar... Using semi-tensor product of matrices, the controllability and stabilizability of finite automata are investigated. By expressing the states, inputs, and outputs in vector forms, the transition and output functions are represented in matrix forms.Based on this algebraic description, a necessary and sufficient condition is proposed for checking whether a state is controllable to another one. By this condition, an algorithm is established to find all the control sequences of an arbitrary length. Moreover, the stabilizability of finite automata is considered, and a necessary and sufficient condition is presented to examine whether some states can be stabilized. Finally, the study of illustrative examples verifies the correctness of the presented results/algorithms. 展开更多
关键词 finite automata CONTROLLABILITY STABILIZABILITY semitensor product of matrices matrix approach
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Classification and Net Primary Productivity of the Southern China's Grasslands Ecosystem Based on Improved Comprehensive and Sequential Classification System(CSCS) Approach 被引量:6
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作者 SUN Zheng-guo SUN Cheng-ming +2 位作者 ZHOU Wei JU Wei-min LI Jian-long 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第4期893-903,共11页
This research classified vegetation types and evaluated net primary productivity (NPP) of southern China's grasslands based on the improved comprehensive and sequential classification system (CSCS), and proposed ... This research classified vegetation types and evaluated net primary productivity (NPP) of southern China's grasslands based on the improved comprehensive and sequential classification system (CSCS), and proposed 5 thermal grades and 6 humidity grades. Four classes of grasslands vegetation were recognized by improved CSCS, namely, tundra grassland class, typical grassland class, mixed grassland class and alpine grassland class. At the type level, 14 types of vegetations (9 grasslands and 5 forests) were classified. The NPP had a trend to decrease from east to west and south to north, and the annual mean NPP was estimated to be 656.3 g C m-2 yr-1. The NPP value of alpine grassland class was relatively high, generally more than 1200 g C m2 yr-1. The NPP value of mixed grassland class was in a range from 1 000 to 1200 g C m-2 yr-1. Tundra grassland class was located in southeastern Tibet with high elevation, and its NPP value was the lowest (〈600 g C m'2yrl). The typical grassland class distributed in most of the area, and its NPP value was generally from 600 to 1000 g C m-2 yr-1. The total NPP value in the study area was 68.46 Tg C. The NPP value of typical grassland class was the highest (48.44 Tg C), and mixed grassland class was the second (16.54 Tg C), followed by alpine grassland class (3.22 Tg C), with tundra grassland class being the lowest (0.25 Tg C). For all the grasslands types, the total NPP of forest meadow was the highest (34.81 Tg C), followed by sparse forest brush (16.54 Tg C), and montane meadow was the lowest (0.01 Tg C). 展开更多
关键词 improved CSCS hydro-thermal pattern southem China grasslands classes and types net primary productivity (NPP)
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System Approach to the Integration of Military and Civilian Productions in China 被引量:1
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作者 Chai Benliang China Defense Science & Technology Information Center, P.O. Box 190, Beijing 100036, China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1992年第3期1-10,共10页
The author uses system analysis to provide system thinkings of the deepening reform of the management of defence science, technology and industry (DSTI) and investigate the system definition of DSTI, the system reform... The author uses system analysis to provide system thinkings of the deepening reform of the management of defence science, technology and industry (DSTI) and investigate the system definition of DSTI, the system reform target, system operational mechanism, institutional structure, coordination and control functions and the orientation of conversion in China. 展开更多
关键词 Economic conversion Military production management System approach
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Changes and Influencing Factors of Maize Production Pattern in China 被引量:1
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作者 Haiyang TANG Jin ZHOU 《Asian Agricultural Research》 2016年第3期47-53,共7页
Since the founding of new China,the maize production pattern took on characteristic of " northern expansion and western movement" : there were great changes in ranking of main producing provinces; southern p... Since the founding of new China,the maize production pattern took on characteristic of " northern expansion and western movement" : there were great changes in ranking of main producing provinces; southern planting area gradually shrank,while central and northern planting area gradually expanded; apart from traditional main producing regions such as northeastern,north China,and southwestern regions,Shanxi- Shaanxi region and northwest region are gradually forming. To further analyze factors promoting changes in maize production pattern,based on 1987- 2013 panel data,we carried our empirical study and obtained five influencing factors: resource endowment,economic environment,market environment,technical conditions,and policies. Per capita farmland,multiple cropping index,water conservancy and irrigation,and benefit cost ratio,and traffic and transportation policies exert positive effect,non-agricultural employment level exerts negative effect,and the significance of natural disasters,market price,and science and technology are inadequate. 展开更多
关键词 MAIZE productION pattern Influencing FACTORS
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Patterns of local recurrence in rectal cancer after a multidisciplinary approach 被引量:14
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作者 Jose M Enríquez-Navascués Nerea Borda +5 位作者 Aintzane Liz-erazu Carlos Placer Jose L Elosegui Juan P Ciria Adelaida Lacasta Luis Bujanda 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第13期1674-1684,共11页
Improvements in surgery and the application of combined approaches to fight rectal cancer have succeeded in reducing the local recurrence (LR) rate and when there is LR it tends to appear later and less often in isola... Improvements in surgery and the application of combined approaches to fight rectal cancer have succeeded in reducing the local recurrence (LR) rate and when there is LR it tends to appear later and less often in isolation. Moreover, a subtle change in the distribution of LRs with respect to the pelvis has been observed. In general terms, prior to total mesorectal excision the most common LRs were central types (perianastomotic and anterior) while lateral and posterior forms (presa-cral) have become more common since the growth in the use of combined treatments. No differences have been reported in the current pattern of LRs as a function of the type of approach used, that is, neo-adjuvant therapies (short-term or long-course radiotherapy, orchemoradiotherapy versus extended lymphadenectomy, though there is a trend towards posterior or presacral LR in patients in the Western world and lateral LR in Asia. Nevertheless, both may arise from the same mechanism. Moreover, as well as the mode of treatment, the type of LR is related to the height of the initial tumor. Nowadays most LRs are related to the advanced nature of the disease. Involvement of the circumferential radial margin and spillage of residual tumor cells from lymphatic leakage in the pelvic side wall are two plausible mechanisms for the genesis of LR. The patterns of pelvic recurrence itself (pelvic subsites) also have important implications for prognosis and are related to the potential success of salvage curative approach. The re-operability for cure and prognosis are generally better for anastomotic and anterior types than for presacral and lateral recurrences. Overall survival after LR diagnosis is lower with radio or chemoradiotherapy plus optimal surgery approaches, compared to optimal surgery alone. 展开更多
关键词 复发率 直肠癌 多学科 联合治疗 手术方法 肿瘤细胞 LRS 辅助疗法
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Application of vertically integrated sampling approach to study of new production via ^(234)Th -^(238)U disequilibria 被引量:1
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作者 Chen Feizhou1 Huang Yipu2 Chen Min2 (1. College of Fishery Science, Shanghai Fisheries University, Shanghai 200090, China 2. Department of Oceanography, Xiamen University, Xiamen 361005, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2000年第2期37-44,共8页
The spatial and temporal distributions of new production vary largely in different sea areas. To understand the level of new production in the sea area studied better, an estimate of new production must be obtained in... The spatial and temporal distributions of new production vary largely in different sea areas. To understand the level of new production in the sea area studied better, an estimate of new production must be obtained in large spatial and temporal scales. The ~234Th/ ~238U disequilibrium is an effective method for the study of new production. Two sampling strategies, vertically integrated sampling ap proach based on trapezoidal integration principle and discrete layer sampling approach, were compared in the studies of the xiamen Bay and the northern South China Sea. The scavenging fluxes and removal fluxes of ~234Th and the residence times for dissolved and particulate ~234Th were calculated. The coinci dent results from two Sampling approach suggest that vertically integrated sampling approach is not only effective and reliable, but also significantly reduces the number and volume of samples. It allows us to study new production by ba ^(234)Th - ^(238)U disequilibria in large spatial scale. 展开更多
关键词 New production vertically integrated Sampling approach ^(234)Th - ^(238)U disequilibria Xia men Bay northern South China Sea
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Productivity Growth, Technological Progress, and Efficiency Change in Vietnamese Manufacturing Industries: A Stochastic Frontier Approach 被引量:1
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作者 Nguyen Khac Minh Pham Van Khanh +1 位作者 Nguyen Thi Minh Nguyen Thi Phuong Anh 《Open Journal of Statistics》 2012年第2期224-235,共12页
This study applies a stochastic frontier production approach to decompose the sources of total productivity (TFP) growth into technical progress and changes in technical efficiency of 8057 firms in Vietnamese manufact... This study applies a stochastic frontier production approach to decompose the sources of total productivity (TFP) growth into technical progress and changes in technical efficiency of 8057 firms in Vietnamese manufacturing industries during 2003-2007. Using both total manufacturing industry and sub-manufacturing industrial regressions, the analysis focuses on the trend of technological progress (TP) and technical efficiency change (TEC), and the role of productivity change in economic growth. According to the estimated results, the annual technical progress for the manufacturing industry and sub-manufacturing industries are calculated directly from the estimated parameters of the translog stochastic frontier production function by taking a partial derivative of output with respect to time t. The average technical changes in manufacturing industry and sub-manufacturing industries are positive, with an average technical change about 5.2%, 5.8%, 5.4%, 11.8%, 4.6%, 4.1%, 7.3%, 4.8%, 4.8% and 4.8% for total sample, food products & beverages, textile & wearing apparel, footwear, paper & products, industrial chemicals, rubber & plastic products, non- metallic mineral, basic & fabricated metal and other sub-industries, respectively. Total TFP in the manufacturing sector has grown at the annual rate of 0.052, although the rate of growth decreased continuously during the sample period. For the sub-industry estimates during the sample period, TFP grew fastest in the footwear sub-industry, with annual average growth rate of 11.8%, followed by the rubber & plastic products with a rate of 7.3%, and the food products & beverages with a rate of 5.8% per annum. 展开更多
关键词 TOTAL Factor productIVITY Technical Efficiency Change TECHNOLOGICAL Progress STOCHASTIC FRONTIER approach VIETNAMESE Manufacturing Industry
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Parametric Design Techniques Applied to Creative Hollow out Product Design with 3D Voronoi Patterns 被引量:2
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作者 Hui-Chin Chang 《Journal of Computer and Communications》 2021年第8期32-47,共16页
The creation of hollow out art includes a variety of materials, techniques and categories, its content mostly emphasizes the ancient philosophy performance of the alternation of virtual and real, and Yin-Yang depends ... The creation of hollow out art includes a variety of materials, techniques and categories, its content mostly emphasizes the ancient philosophy performance of the alternation of virtual and real, and Yin-Yang depends on the essence of Chinese culture deduction. If this feature is applied to product design, in addition to emphasizing functional orientation, this traditional arts integration with the new media, will give users a different visual inspire. This thesis is mainly in view of the importance of hollow out art in Chinese cultural heritage, and the 3D hollow out production craft has gradually lost. Therefore, the Delaunay triangle is constructed based on the Convex Hull interpolation algorithm, and the Voronoi Diagram feature is constructed based on the Divide and Conquer algorithm. And with Rhino modeling software as the main body, combined with the application of the parametric plug-in design program (GH), the 3D models of the parametric creative hollow pen holder and the parametric creative hollow lampshade were respectively completed. The traditional craftsmanship is integrated into the modern manufacturing process with innovative techniques, and the Chinese cultural spirit and beauty of nature are successfully connected. 展开更多
关键词 Parametric Design Hollow Out product 3D Voronoi patterns
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Spatio-temporal Pattern of Net Primary Productivity in Hengduan Mountains area, China: Impacts of Climate Change and Human Activities 被引量:11
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作者 CHEN Tiantian PENG Li +1 位作者 LIU Shaoquan WANG Qiang 《Chinese Geographical Science》 SCIE CSCD 2017年第6期948-962,共15页
Net primary productivity(NPP), a metric used to define and identify changes in plant communities, is greatly affected by climate change, human activities and other factors. Here, we used the Carnegie-Ames-Stanford App... Net primary productivity(NPP), a metric used to define and identify changes in plant communities, is greatly affected by climate change, human activities and other factors. Here, we used the Carnegie-Ames-Stanford Approach(CASA) model to estimate the NPP of plant communities in Hengduan Mountains area of China, and to explore the relationship between NPP and altitude in this region. We examined the mechanisms underlying vegetation growth responses to climate change and quantitatively assessed the effects of ecological protection measures by partitioning the contributions of climate change and human activities to NPP changes. The results demonstrated that: 1) the average total and annual NPP values over the years were 209.15 Tg C and 468.06 g C/(m2·yr), respectively. Their trend increasingly fluctuated, with spatial distribution strongly linked to altitude(i.e., lower and higher NPP in high altitude and low altitude areas, respectively) and 2400 m represented the marginal altitude for vegetation differentiation; 2) areas where climate was the main factor affecting NPP accounted for 18.2% of the total research area, whereas human activities were the primary factor influencing NPP in 81.8% of the total research area, which indicated that human activity was the main force driving changes in NPP. Areas where climatic factors(i.e., temperature and precipitation) were the main driving factors occupied 13.6%(temperature) and 6.0%(precipitation) of the total research area, respectively. Therefore, the effect of temperature on NPP changes was stronger than that of precipitation; and 3) the majority of NPP residuals from 2001 to 2014 were positive, with human activities playing an active role in determining regional vegetation growth, possibly due to the return of farmland back to forest and natural forest protection. However, this positive trend is decreasing. This clearly shows the periodical nature of ecological projects and a lack of long-term effectiveness. 展开更多
关键词 净初级生产力 人类活动 气候变化 时空格局 中国 低海拔地区 植被生长 NPP
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Product Family Design Methodology Using Object-Oriented Approach
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作者 WANG Ai-min, MENG Ming-chen, HUANG Jing-yuan (Department. of Precision Instruments and Mechanology, Tsinghua Univers ity, Beijing 100084, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期141-142,共2页
The serious competition environment of global marke t requests the enterprise to change traditional product development strategy and a dopt new theory in order to meet diverse customer needs while maintaining near m a... The serious competition environment of global marke t requests the enterprise to change traditional product development strategy and a dopt new theory in order to meet diverse customer needs while maintaining near m ass production efficiency, which is the main philosophy of mass customization. P roduct family design is research focus at present and also is the core technolog y of DFMC (design for mass customization). Firstly, this paper explores the fund amental issues of product family, such as concepts of modularity, commonality/di versity, product platform and product family architecture etc. We compare the te rminology between product family and object-oriented approach in the next step. Thirdly, this paper puts forwards one product family design methodology based o n product platform and under different phase of product life cycle constrains, f or example, functional, assembly and service etc. At the end section of this pap er, we applied, the object-oriented approach in above mentioned product family design methodology to realize the design process. In one word, this paper propos ed one product family design methodology based on object oriented approach and p roduct life cycle consideration, especially the conjointness of characteristic o f OOA and concepts of product family. The main property of OOA are encapsulation , inherence and polymorphism. Encapsulation can represent the module or building blocks of product family. Inherence can be extended to describe the modularity and commonality, and also be used to construct variant space. Alternative specif ic of product family architecture can be embodied with polymorphism. And fin aly, we give the future work contents. In order to derive the product platform a nd achieve modularity and commonality/diversity, interface management between bu ilding block is necessary. The question is how the OOA can be applied in interfa ce management to get our aim OOA is the basis of many information management sy stem, then the question is how to build one system to manage the information of product family and support mass customization The third question is how to deve lop one computer aided tool to facilitate the application of OOA for product fam ily design, even be used to category of design for mass customization. 展开更多
关键词 product family design product platform object- oriented approach (OOA) product life cycle
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Analysis of the Southern China Tilapia Production and Economic Benefits of Different Breeding Patterns in 2018
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作者 Lirong BAI Dahui YU 《Agricultural Biotechnology》 CAS 2019年第5期65-69,共5页
Cost-benefit analysis and breakeven point were used to analyze the production cost and economic benefit of tilapia pond monoculture and polyculture.From the aspects of tilapia production and economic benefit,this pape... Cost-benefit analysis and breakeven point were used to analyze the production cost and economic benefit of tilapia pond monoculture and polyculture.From the aspects of tilapia production and economic benefit,this paper summarized the current production status and the characteristics of tilapia industry development and analyzed its developing trend.The results indicated that feed cost,pond rates and labor cost are the main production costs,and the production cost of polyculture is significantly lower than that of monoculture.Through comparative analysis,it is proposed that the tilapia industry should be reasonably guided to the intensive,standardized and pollution-free direction.Specifically,it is necessary to improve the coverage of improved varieties,strengthen disease prevention and control and promote the healthy farming model of tilapia.We also should strengthen the training of tilapia production techniques and the quality and safety testing of tilapia products,and accelerate the development of tilapia industrialization,so as to promote the sustainable and healthy development of tilapia industry. 展开更多
关键词 TILAPIA BREEDING pattern productION status Economic BENEFIT Development TREND
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Patterns of international governance in the Arctic and China's approach
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作者 ZHAO Long 《Advances in Polar Science》 2016年第3期170-179,共10页
The process of rapid change in the Arctic is creating both opportunities and challenges. This paper highlights interactions between different actors in the Arctic in response to multidimensional environmental, politic... The process of rapid change in the Arctic is creating both opportunities and challenges. This paper highlights interactions between different actors in the Arctic in response to multidimensional environmental, political, commercial, and human challenges. It shows that international governance in the Arctic can be characterized by global, multilateral, and regional patterns derived from different mechanisms such as the Arctic Council or the Ilulissat declaration platform, and these interactions are based on common acknowledgment of challenges, mutual interests, and coordinated actions. The paper also examines China's participation in international governance in the Arctic. Distinguish from non-Arctic states in a general sense, China as an important stakeholder has both the rights and the capacity to be engaged in multilevel governance patterns. The substantive contribution of China's participation--an explorer in scientific cooperation, a pioneer promoting environmental protection, a potential consumer and investor in relation to economic opportunities, and a promoter of local development^are deeply interdepended with the future of development of three ~overnance patterns relatin~ to international ~overnance in the Arctic. 展开更多
关键词 ARCTIC governance patterns China's approach
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Regional Carbon Emission Performance of Pig Production in China according to Malmquist-DEA Approach
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作者 Wenbin WANG Zhenhong QI +1 位作者 Xinrui LI Lanya WU 《Asian Agricultural Research》 2017年第6期55-60,66,共7页
As pig production is a main contributor of greenhouse gas(GHG) emissions from livestock sector,the carbon emissions of pig production are attracting increasing attention,especially in the developing countries. Based o... As pig production is a main contributor of greenhouse gas(GHG) emissions from livestock sector,the carbon emissions of pig production are attracting increasing attention,especially in the developing countries. Based on the panel data of 30 provinces in China from 2001 to 2012,this paper measures the provincial carbon emission performance(CEP) of pig production and we use a Malmquist DEA approach to analyze the decomposition which includes desirable and undesirable output. Furthermore,the regional disparity in carbon emission performance of pig production is also analyzed and finally the convergence is tested. The main results are as follows:(i) there are provincial differences in carbon emission performance changing of pig production in China,and the carbon emission performance of pig production in 30 provinces has a downward trend during this period;(ii) among China’s three major economic regions,in terms of carbon emission performance of pig production,they are ranked in descending order as follows: Western China,Central China and Eastern China;(iii) convergence testing shows that there is a convergence trend for carbon emission performance both nationally and for the three regions. 展开更多
关键词 Carbon emission performance Pig production Malmquist DEA approach CONVERGENCE
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<i>PP</i>and <i>P<span style='text-decoration:overline;'>P</span></i>Multi-Particles Production Investigation Based on CCNN Black-Box Approach
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作者 El-Sayed A. El-Dahshan 《Journal of Applied Mathematics and Physics》 2017年第6期1398-1409,共12页
The multiplicity distribution (P(nch)) of charged particles produced in a high energy collision is a key quantity to understand the mechanism of multiparticle production. This paper describes the novel application of ... The multiplicity distribution (P(nch)) of charged particles produced in a high energy collision is a key quantity to understand the mechanism of multiparticle production. This paper describes the novel application of an artificial neural network (ANN) black-box modeling approach based on the cascade correlation (CC) algorithm formulated to calculate and predict multiplicity distribution of proton-proton (antiproton) (PP and PP ) inelastic interactions full phase space at a wide range of center-mass of energy . In addition, the formulated cascade correlation neural network (CCNN) model is used to empirically calculate the average multiplicity distribution nch> as a function of . The CCNN model was designed based on available experimental data for = 30.4 GeV, 44.5 GeV, 52.6 GeV, 62.2 GeV, 200 GeV, 300 GeV, 540 GeV, 900 GeV, 1000 GeV, 1800 GeV, and 7 TeV. Our obtained empirical results for P(nch), as well as nch> for (PP and PP) collisions are compared with the corresponding theoretical ones which obtained from other models. This comparison shows a good agreement with the available experimental data (up to 7 TeV) and other theoretical ones. At full large hadron collider (LHC) energy ( = 14 TeV) we have predicted P(nch) and nch> which also, show a good agreement with different theoretical models. 展开更多
关键词 Proton-Proton and Proton-Antiproton Collisions Multiparticle productION Multiplicity Distributions Intelligent Computational Techniques CCNN-Neural Networks BLACK-BOX Modeling approach
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Spatio-temporal Pattern and Driving Forces of Comprehensive Agricultural Productivity in Jilin Province,China
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作者 LIU Yunda TONG Lianjun 《Chinese Geographical Science》 SCIE CSCD 2020年第3期493-504,共12页
Improving comprehensive agricultural productivity is an important measure to realize agricultural modernization.Based on the data from Jilin Statistical Yearbook,this study analyzed the spatial and temporal characteri... Improving comprehensive agricultural productivity is an important measure to realize agricultural modernization.Based on the data from Jilin Statistical Yearbook,this study analyzed the spatial and temporal characteristics of comprehensive agricultural productivity discrepancy in the main agricultural production areas of Jilin Province,China.The comprehensive agricultural productivity of 25 county-level administrative units were evaluated by a comprehensive index system based on five aspects which included 20 indicators from 2004 to 2017.The pattern of the discrepancy was analyzed by the spatial differentiation indices and spatial convergence theory.The results were as follows:1) the overall comprehensive agricultural productivity was in a ’W-type’ rising trend;2) the discrepancy was in’inverted W-type’ trend;3) the spatial distribution characteristics were mainly discrete plaque and ’inverted V-type’;4) the formation of differences was forced by a combination of internal and external driving forces.Our study demonstrates the effectiveness of rising agricultural productivity and the level of economic and social developments in different counties in Jilin Province. 展开更多
关键词 spatio-temporal pattern comprehensive agricultural productivity spatial convergence/divergence driving forces Jilin Province China
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Current Situation and Approaches Relating to Construction of Agricultural Production and Operation Development Capacity for Rural Households in Hubei Province
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作者 Jing ZENG 《Asian Agricultural Research》 2018年第6期18-22,共5页
The main body of household operation in the rural household contract responsibility system of our country has developed to the present stage,and has formed the situation that three kinds of rural households coexist,na... The main body of household operation in the rural household contract responsibility system of our country has developed to the present stage,and has formed the situation that three kinds of rural households coexist,namely,ordinary rural households,major professional households and family farms. The agricultural production and operation of three kinds of household plays an important role in supporting the rapid development of modern agriculture in China. Under the new situation of deepening the rural reform and realizing the goal of well-off society in an all-round way,it is of great practical significance to make a thorough investigation and study on the present situation and approaches relating to the construction of the agricultural production and operation capacity for the three kinds of rural households. 展开更多
关键词 Rural households Agricultural production and operation development capacity Analysis of current situation Construction approaches
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Research on the Significance and Approaches of Productive Landscape Introduced in Residential Districts
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作者 Kai WANG 《Agricultural Science & Technology》 CAS 2017年第2期199-200,218,共3页
With the urbanization increasingly advancing at a high speed, a large number of farmlands have been turned into building lands, which leads the urban-rural conflicts more and more evident than before. Introducing the ... With the urbanization increasingly advancing at a high speed, a large number of farmlands have been turned into building lands, which leads the urban-rural conflicts more and more evident than before. Introducing the concept of productive landscape into residential districts, could relieve the contradiction between agricultural land and urban construction land, improve the modern lifestyle, provide a new perspective of landscape design philosophy. In this paper, based on the analysis of the present situation of residential green space, the significance and approaches of productive landscape in residential areas have been put forward, and suggestions of daily management and countermeasures about agricultural pollution problem have also been given. 展开更多
关键词 居住区景观 生产性 住宅区 城市建设用地 居住区绿地 农业用地 城市化进程 生活方式
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