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Development characteristics and controlling factors of fractures in lacustrine shale and their geological significance for evaluating shale oil sweet spots in the third member of the Shahejie Formation in the Qikou Sag, Bohai Bay Basin
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作者 Xu Zeng Tao Yang +5 位作者 Jian-Wei Feng Cong-Sheng Bian Ming Guan Wei Liu Bing-Cheng Guo Jin Dong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期791-805,共15页
Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fra... Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in these areas when structural fractures are present and the source, and storage spaces are separated. 展开更多
关键词 FRACTURES development characteristics controlling factors Shale oil Sweet spot
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Interaction and coordinated development between desertification control and social economy in Xizang,China
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作者 ZHU Cai-xia ZHENG Yu-jie +1 位作者 LIU Si-yu QIN Tao 《Ecological Economy》 2024年第2期160-177,共18页
Based on the general requirements of the coordinated development of"ecological livable"and"affluent life"in the rural revitalization strategy,the evaluation index system of desertification control ... Based on the general requirements of the coordinated development of"ecological livable"and"affluent life"in the rural revitalization strategy,the evaluation index system of desertification control was constructed,the interaction between desertification control and regional social economy and the internal space-time coordination mechanism were explored,and the quality of desertification control and its coordination degree with regional economic development were quantitatively analyzed.The decoupling mechanism of desertification governance society economy system were analyzed,and the high level for the government to promote desertification governance,constructing ecological economy coordinated development pattern to provide decision basis to Xizang desertification governance-social economic system interaction and coupling coordination development as the research object,introducing the coupling decoupling model to measure the coupling coordination model and system coordination and decoupling decoupling.Desertification control in Xizang shows a trend of gradual improvement,but the overall level is still not high and there is a lot of room for optimization.The coupling coordination degree of desertification control-social and economic system is in a steady fluctuation trend,rising from D value less than 0.55 in 2004 to 0.87 in 2018,in a state of coordinated development(good),and grey prediction analysis shows that D value is in a continuous rise.The coupling coordination degree of the six prefecture-level cities in Xizang and Ngari region is different in time and space,but the overall development trend is coordinated.The development index of desertification control and the socio-economic development index show the interaction of strong decoupling,strong negative decoupling and weak decoupling,and there are interaction effects of desertification control,economic development and social development at different scales. 展开更多
关键词 desertification control coupling coordination model decoupling model economic development
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Camptothecin and 10-Hydroxycamptothecin Accumulate Differentially Under Specific Developmental Control in Camptotheca acuminata 被引量:11
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作者 祖元刚 唐中华 +1 位作者 于景华 赵春建 《Acta Botanica Sinica》 CSCD 2003年第4期494-499,共6页
Camptotheca acuminata Decaisne is a tree unique to China, producing terpenoid indole alkaloid (TIA), camptothecin (CPT), and 10-hydroxycamptothecin (HCPT), which possesses strong anti-cancer bioactivity. The dynamics ... Camptotheca acuminata Decaisne is a tree unique to China, producing terpenoid indole alkaloid (TIA), camptothecin (CPT), and 10-hydroxycamptothecin (HCPT), which possesses strong anti-cancer bioactivity. The dynamics of HCPT and CPT during seed maturation, seed germination, postgerminative development and daily growth were measured by High Performance Liquid Chromatography (HPLC). This article provides some evidence for presenting the theory that each characteristic of HCPT and CPT accumulation is under developmental regulation and then attempt to elucidate the metabolic relationships between them. HCPT accumulates particularly in young tissues and organs and is relatively unstable, while the distribution of CPT is more ubiquitous and stable. Their different distribution properties suggest that HCPT and CPT are differentially regulated and play distinct roles:during development. 展开更多
关键词 Camptotheca acuminata CAMPTOTHECIN 10-HYDROXYCAMPTOTHECIN control development
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Development Characteristics and Control Measures for Semiothisa cineraria Bremer & Grey 被引量:1
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作者 唐浩 李军民 +2 位作者 吴家全 高华清 张松光 《Agricultural Science & Technology》 CAS 2014年第6期933-936,共4页
The development characteristics of Semiothisa cinerearia Bremer & Grey was summarized, and we also put forward the control measures of well completing insect surveys to provide scientific basis for the control and ac... The development characteristics of Semiothisa cinerearia Bremer & Grey was summarized, and we also put forward the control measures of well completing insect surveys to provide scientific basis for the control and actively carrying out comprehensive management to control the pests damage in the economic permissible level. 展开更多
关键词 Semiothisa cinerearia Bremer Grey development characteristics control measures
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Research and Development Trend of Shape Control for Cold Rolling Strip 被引量:22
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作者 Dong-Cheng Wang Hong-Min Liu Jun Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第5期1248-1261,共14页
Shape is an important quality index of cold rolling strip. Up to now, many problems in the shape control domain have not been solved satisfactorily, and a review on the research progress in the shape control domain ca... Shape is an important quality index of cold rolling strip. Up to now, many problems in the shape control domain have not been solved satisfactorily, and a review on the research progress in the shape control domain can help to seek new breakthrough directions. In the past 10 years, researches and applications of shape control models, shape control means, shape detection technology, and shape con- trol system have achieved significant progress. In the aspect of shape control models, the researches in the past improve the accuracy, speed and robustness of the models. The intelligentization of shape control models should be strengthened in the future. In the aspect of the shape control means, the researches in the past focus on the roll opti- mization, mill type selection, process optimization, local strip shape control, edge drop control, and so on. In the future, more attention should be paid to the coordination control of both strip shape and other quality indexes, and the refinement of control objective should be strengthened. In the aspects of shape detection technology and shape control system, some new types of shape detection meters and shape control systems are developed and have successfully indus- trial applications. In the future, the standardization of shape detection technology and shape control system should be promoted to solve the problem of compatibility. In general,the four expected development trends of shape control for cold roiling strip in the future are intelligentization, coordi- nation, refinement, and standardization. The proposed research provides new breakthrough directions for improv- ing shape quality. 展开更多
关键词 Cold rolling strip - Shape control development trend Theory models Shape detectioncontrol system
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A Sand Control and Development Model in Sandy Land Based on Mixed Experiments of Arsenic Sandstone and Sand: A Case Study in Mu Us Sandy Land in China 被引量:13
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作者 WANG Ni XIE Jiancang HAN Jichang 《Chinese Geographical Science》 SCIE CSCD 2013年第6期700-707,共8页
Serious desertification caused by human activity and climate change,in addition to water loss and soil erosion related to arsenic sandstone in the Mu Us Sandy Land,lead to severe scarcity of soil and water resources,w... Serious desertification caused by human activity and climate change,in addition to water loss and soil erosion related to arsenic sandstone in the Mu Us Sandy Land,lead to severe scarcity of soil and water resources,which causes worse local agricultural conditions accordingly.Many physical properties of arsenic sandstone is complementary with that of sand,arsenic sandstone is therefore supposed to be blended to enhance water productivity and arability of sandy land.Container experiments are carried out to study the enhancement of water holding capacity of the mixture,the blending ratio of arsenic sandstone and sand,and the proper size of the arsenic sandstone particles,respectively.The results of the experiments show that particle size of 4 cm with a ratio of 1∶2 between arsenic sandstone and sand are the proper parameters on blending.Both water content and fertility increase after blending.Water use efficiency in the mixture is 2.7 times higher than that in sand by the water release curves from experiments.Therefore,a new sand control and development model,including arsenic sandstone blending with sand,efficient water irrigation management and reasonable farming system,is put forward to control and develop sandy land so that water-saving agriculture could be developed.Demonstration of potato planting about 153.1 ha in area in the Mu Us Sandy Land in China indicates that water consumption is 3018 m3/ha in the whole growth period.It means that about 61%of irrigation water can be saved compared with water use in coarse sand without treatment.Recycle economic mode and positive feedback of sand resource-crop planting-soil resource are constructed,which changes sand into arable soil and make it possible to develop water-saving agriculture on it.The proposed model will be helpful for soil-water resources utilization and management in the Mu Us Sandy Land. 展开更多
关键词 soil-water resource arsenic sandstone sand control and development model water-saving effect Mu Us Sandy Land
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Research on rapid development platform of PLC control system 被引量:3
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作者 Wang Xing Tang Xianwei +1 位作者 Dong Zengshou Zhen Liaomo 《High Technology Letters》 EI CAS 2021年第2期210-217,共8页
In the field of industrial process control,a fast-development platform for programmable logic controller(PLC)systems is designed in order to solve two main problems of rapid development of PLC control system and progr... In the field of industrial process control,a fast-development platform for programmable logic controller(PLC)systems is designed in order to solve two main problems of rapid development of PLC control system and programmability of controlling software.In the aspect of design,the platform is composed of hardware controlling and software monitoring and is taking industrial computer as the core.Under the Windows environment,the platform establishes the control instruction set,develops the configuration function and visual programming function of the monitoring software and it integrates PLC controller based on Visual Basic software.In order to achieve the function of data monitoring,it has realized the serial communication between computer and PLC by using RS-485 and RS-232 serial ports line communication.The platform designs the intelligent instruction scheduling strategy by studying the encoding and decoding rules of the communication instruction set.It proposes a method for rapidly developing control programs by adopting the expert control mode,which enables clients to develop and modify programs conveniently by importing instructions in a non-coded manner.After experimental testing,the platform is proved successful achieving both the rapid development of PLC control system and the rapid modification of monitoring software. 展开更多
关键词 programmable logic controller(PLC) rapid development instruction set instruction scheduling expert control
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Thailand's economic growth and structural development projections in the context of environmental control 被引量:1
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作者 Sompote Kunnoot 《Chinese Journal of Population,Resources and Environment》 2015年第3期272-280,共9页
Projections for 20 years of economic growth and change in the structure of the Thai economy were made for 180 sectors using a computable general equilibrium(CGE) model to compare the following four scenarios:(1) stand... Projections for 20 years of economic growth and change in the structure of the Thai economy were made for 180 sectors using a computable general equilibrium(CGE) model to compare the following four scenarios:(1) standard growth with infinite supply of factors,(2) finite land supply,(3) fixed use of agricultural chemicals,and(4) combined finite land supply with fixed use of agricultural chemicals.The computable projections suggest that the economic cost of hypothetical environmental control in agriculture is small and further weakened by urbanization.The computed structural development points to efficiency improvements specific to sectors to return the economy to balanced growth. 展开更多
关键词 STRUCTURAL development ENVIRONMENTAL control ECONOMIC growth PROJECTION
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Quality Control of Tramadol in Kisangani: Development, Validation, and Application of a UV-Vis Spectroscopic Method 被引量:4
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作者 Marguerite Borive Amani Jérémie Mbinze Kindenge +4 位作者 Emile Tweni Baruti Elodie Nsasi Bakiantima Salomon Batina Agasa Philippe Hubert Roland Marini Djang’eing’a 《American Journal of Analytical Chemistry》 2021年第8期295-309,共15页
<strong>Context:</strong> Substandard and falsified medicines are circulating in low-income countries mostly without any control. We availed a simple and not expensive UV-Vis spectroscopic method to evalua... <strong>Context:</strong> Substandard and falsified medicines are circulating in low-income countries mostly without any control. We availed a simple and not expensive UV-Vis spectroscopic method to evaluate the quality of tramadol in Kisangani before and during the Covid-19 period. <strong>Methods:</strong> For the analytical quantitative method, an experimental design was applied to set up the optimal levels of the selected factors, namely, pH of dissolution medium, type of cuvette, and wavelength. Taking into account the capsule pharmaceutical formulation within 80 - 120 μg&middotmL<sup>-1</sup> concentration range, we analyzed 89 tramadol samples from pharmacies and hospitals of the six Kisangani municipalities. <strong>Results:</strong> pH showed a significant effect on absorbance, whereas quartz cuvette and wavelength did not. A typical 100 μg&middotmL<sup>-1</sup> tramadol solution gave an absorbance of 0.64 at 272 nm. Validation highlighted a matrix effect observed with a 6% bias. A correction factor of 0.9372 allowed to improve the accuracy profile, which were then totally included within the 10% acceptance limits. Quality control revealed that 25 samples out of 89 were not compliant in terms of manufacturing license, registration status in DRC and content as well. <strong>Conclusion:</strong> This study showed that the strengthening of analytical strategy in Kisangani is a need. 展开更多
关键词 TRAMADOL UV-Vis Spectroscopy Method development VALIDATION Quality control
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Gα_s signaling controls intramembranous ossification during cranial bone development by regulating both Hedgehog and Wnt/β-catenin signaling 被引量:7
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作者 Ruoshi Xu Sanjoy Kumar Khan +4 位作者 Taifeng Zhou Bo Gao Yaxing Zhou Xuedong Zhou Yingzi Yang 《Bone Research》 CAS CSCD 2018年第4期340-354,共15页
How osteoblast cells are induced is a central question for understanding skeletal formation. Abnormal osteoblast differentiation leads to a broad range of devastating craniofacial diseases. Here we have investigated i... How osteoblast cells are induced is a central question for understanding skeletal formation. Abnormal osteoblast differentiation leads to a broad range of devastating craniofacial diseases. Here we have investigated intramembranous ossification during cranial bone development in mouse models of skeletal genetic diseases that exhibit craniofacial bone defects. The GNAS gene encodes Gαs that transduces GPCR signaling. GNAS activation or loss-of-function mutations in humans cause fibrous dysplasia(FD) or progressive osseous heteroplasia(POH) that shows craniofacial hyperostosis or craniosynostosis, respectively. We find here that, while Hh ligand-dependent Hh signaling is essential for endochondral ossification, it is dispensable for intramembranous ossification, where Gαsregulates Hh signaling in a ligand-independent manner. We further show that Gαscontrols intramembranous ossification by regulating both Hh and Wnt/β-catenin signaling. In addition, Gαsactivation in the developing cranial bone leads to reduced ossification but increased cartilage presence due to reduced cartilage dissolution, not cell fate switch. Small molecule inhibitors of Hh and Wnt signaling can effectively ameliorate cranial bone phenotypes in mice caused by loss or gain of Gnas function mutations, respectively. Our work shows that studies of genetic diseases provide invaluable insights in both pathological bone defects and normal bone development, understanding both leads to better diagnosis and therapeutic treatment of bone diseases. 展开更多
关键词 s signaling controls intramembranous ossification during cranial bone development by regulating both Hedgehog and Wnt catenin signaling
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Development and Control of Underwater Gliding Robots:A Review 被引量:1
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作者 Jian Wang Zhengxing Wu +2 位作者 Huijie Dong Min Tan Junzhi Yu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第9期1543-1560,共18页
As one of the most effective vehicles for ocean development and exploration,underwater gliding robots(UGRs)have the unique characteristics of low energy consumption and strong endurance.Moreover,by borrowing the motio... As one of the most effective vehicles for ocean development and exploration,underwater gliding robots(UGRs)have the unique characteristics of low energy consumption and strong endurance.Moreover,by borrowing the motion principles of current underwater robots,a variety of novel UGRs have emerged with improving their maneuverability,concealment,and environmental friendliness,which significantly broadens the ocean applications.In this paper,we provide a comprehensive review of underwater gliding robots,including prototype design and their key technologies.From the perspective of motion characteristics,we categorize the underwater gliding robots in terms of traditional underwater gliders(UGs),hybrid-driven UGs,bio-inspired UGs,thermal UGs,and others.Correspondingly,their buoyancy driven system,dynamic and energy model,and motion control are concluded with detailed analysis.Finally,we have discussed the current critical issues and future development.This review offers valuable insight into the development of next-generation underwater robots well-suited for various oceanic applications,and aims to gain more attention of researchers and engineers to this growing field. 展开更多
关键词 Buoyancy driven motion control oceanic applications system development underwater gliding robots
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The control effect of low-amplitude structure on oil-gaswater enrichment and development performance of ultra-low permeability reservoirs 被引量:1
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作者 WANG Jianmin ZHANG San +4 位作者 DU Wei LI Le QIAO Zhen ZHANG Jun DUAN Mengyue 《Petroleum Exploration and Development》 2019年第4期767-778,共12页
Based on drilling, logging, test production and dynamic monitoring data, the control effects of low-amplitude structure on hydrocarbon accumulation and development performance of ultra-low permeability reservoirs were... Based on drilling, logging, test production and dynamic monitoring data, the control effects of low-amplitude structure on hydrocarbon accumulation and development performance of ultra-low permeability reservoirs were discussed by using the methods of dense well pattern, multi-factor geological modeling, macro and micro analysis and static and dynamic analysis. The results show that the low-amplitude structure always had a significant control and influence on the distribution and accumulation of original hydrocarbon and water and the evolution trend of water flooding performance in ultra-low permeability reservoirs, and it was not only the direction of oil and gas migration, but also a favorable place for relative accumulation of oil and gas. The controlling effect of low-amplitude structure on ultra-low permeability reservoir mainly depended on its tectonic amplitude and scale;the larger the tectonic amplitude and scale, and the higher the tectonic position of the low amplitude structure, the better the reservoir characteristic parameters, oil and gas enrichment degree and development effect, and the larger the spatial scope it controlled and influenced;water cut and oil well output always fluctuated orderly with the height of the low-amplitude structure;the dynamic response of waterflooding was closely related to the relative structural position of the injection and production wells;the injected water always advanced to the low-lying area of the structure first and then moved up to the high-lying area of the structure gradually;with the continuous expansion of the flooded area, part of the oil and gas in the low-lying part of the structure was forced to be distributed to the high part of the structure, resulting in a new oil and gas enrichment, so that the dynamic reserves of oil wells in the high part increased, and the production capacity remained stable. 展开更多
关键词 ultra-low PERMEABILITY RESERVOIRS LOW-AMPLITUDE structure OIL-GAS-WATER ENRICHMENT development dynamics control effect
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The Development and Research on the Coordinate Control Strategy Between Turbine and Boiler in Fossil Power Plant
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作者 WEI Shuangying (Management School,Wuhan University of Technology,Wuhan 430070,China) 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S1期363-366,共4页
Based on the research on domestic and international automatic technical development in fossil power plant,the paper analyses the recent situation of the coordinate control system between turbine and boiler of domestic... Based on the research on domestic and international automatic technical development in fossil power plant,the paper analyses the recent situation of the coordinate control system between turbine and boiler of domestic fossil Power Plant,provides the development thought of coordinate control system between turbine and boiler,and describes the application prospect in control system of fossil power plant combining with the application experience. 展开更多
关键词 FOSSIL power PLANT COORDINATE control system BETWEEN TURBINE and BOILER development and research
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THE ROLLING DEVELOPMENT MODEL OF ECOLOGICAL ECONOMY COMBINED WATER CONSERVANCY CONSTRUCTION WITH SCHISTOSOMIASIS CONTROL
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作者 LI HONG FAN WENTAO Wuhan Institute of Mathematical Sciences, Academia Sinica 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1996年第1期109-114,共6页
On the basis of classification of geographical properties a rolling develop-ment goal programming model is formulated in correspondence with the ecopatterngroup in Four-Lake Area. In this model, the control of schisto... On the basis of classification of geographical properties a rolling develop-ment goal programming model is formulated in correspondence with the ecopatterngroup in Four-Lake Area. In this model, the control of schistosomiasis and strengthen-ing of the drainage-storage function are both regarded as ecological measures duringthe process of multi-year(r_0) ecological economic rolling development to make theecoagricultural system in this area ioto a stably operating, ordered, and good cyclicsystem under the support of some controllable factors. 展开更多
关键词 Rolling development goal programming ecological economy schistosomiasis control drainage-storage.
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Software Development for Digital Control of WDW Series Testing Machine and Measurement of K_(IC)
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作者 黄兴 马杭 程昌钧 《Journal of Shanghai University(English Edition)》 CAS 2005年第1期58-61,共4页
Software has been developed for digital control of WDW series testing machine and the measurement of fracture toughness by modularized design. Development of the software makes use of multi-thread and serial communica... Software has been developed for digital control of WDW series testing machine and the measurement of fracture toughness by modularized design. Development of the software makes use of multi-thread and serial communication techniques, which can accurately control the testing machine and measure the fracture toughness in real-time. Three-point bending specimens were used in the measurement. The software operates stably and reliably, expanding the function of WDW series testing machine. 展开更多
关键词 testing machine digital control measurement of fracture toughness software development.
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Transcriptional control of GABAergic neuron development in the dorsal spinal cord
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作者 Huang Jing Wu Shengx 《Journal of Medical Colleges of PLA(China)》 CAS 2008年第3期183-188,共6页
GABAergic neurons are the major inhibitory interneurons that powerfully control the function of spinal neuronal networks.In recent years,tremendous progresses have been made in understanding the transcriptional contro... GABAergic neurons are the major inhibitory interneurons that powerfully control the function of spinal neuronal networks.In recent years,tremendous progresses have been made in understanding the transcriptional control of GABAergic neuron development in the dorsal spinal cord.New experimental approaches provide a relatively high throughput way to study the molecular regulation of subgroup fate determination.Our understanding of the molecular mechanisms on GABAergic neuron development in the dorsal spinal cord is rapidly expanding.Recent studies have defined several transcription factors that play essential roles in GABAergic neuron development in the spinal dorsal horn.Here,we review results of very recent analyses of the mechanisms that specify the GABAergic neuron development in the dorsal spinal cord,especially the progresses in the homeodomain(HD) and basic-helix-loop-helix(bHLH) containing transcription factors. 展开更多
关键词 GABAergic neuron development Transcriptional control Dorsal spinal cord
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Computerised Development Control and Approval System for City Hall of Kuala Lumpur
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作者 Ahris Yaakup Yazid Abu Bakar +2 位作者 Mohd Nuruddin Abdul Kadir Susilawati Sulaiman 《Geo-Spatial Information Science》 2004年第1期39-49,共11页
This paper will discuss the computerised developm en t control and approval system being developed for the Planning and Development C ontrol Department, City Hall of Kuala Lumpur, with stress on the GIS architectur e ... This paper will discuss the computerised developm en t control and approval system being developed for the Planning and Development C ontrol Department, City Hall of Kuala Lumpur, with stress on the GIS architectur e developed within the system. The prospects and challenges towards implementati on of the system are also discussed. 展开更多
关键词 GIS architecture computerised development control and approval system Cityhall of Kuala lumpur
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A Control Theoretical Model of Web Service Value Development
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作者 Anthony S. White Doreen Nielsen Michael Censlive 《Open Journal of Modelling and Simulation》 2019年第2期125-147,共23页
This paper describes a control theoretical model of collaborative value development. This model is designed to assist managers in choosing parameters that are critical to the development process in service design and ... This paper describes a control theoretical model of collaborative value development. This model is designed to assist managers in choosing parameters that are critical to the development process in service design and support their Business Model. This methodology uses control system modelling of web-based service value generation implemented in SIMULINK/MATLAB. An application based on public domain Wikipedia data is used to validate and develop the model. A control theoretic model applied to the creation of Wikipedia articles shows very good agreement with Wikipedia published data for the time dependent growth in articles produced, and editors used, well within the variability of parametric data listed publically justifying the principle equations used in the model. This development and fine tuning of the model has been limited by the publically available data. To obtain a more accurate model in this area would need the co-operation of web service organisations to reveal confidential data. This modelling procedure can produce a decision support process for service design and could, with modification be applied much more widely to other choices in service design/implementation, even allowing for user contribution to be evaluated. This work shows how subjective judgements on value and other intangibles need to be continually re-evaluated. Such methodology has not been applied elsewhere to value generation applications. It could be used to rank contributions from co-creators for reward sharing. 展开更多
关键词 Service VALUE control THEORETICAL Model Simulink Simulation WIKIPEDIA development
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Farmers' Perception of Soil Erosion Control Measures: Implications for Sustainable Development in Agriculture and Environment in South East, Nigeria
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作者 Simeon Okpoto Eze Esther Etenmugonwa Osahon 《Journal of Life Sciences》 2016年第3期161-169,共9页
The study investigated farmers' perception of soil erosion control measures and highlighted implications for sustainable development in agriculture and environment in southeast, Nigeria. Purposive, multistage and ran... The study investigated farmers' perception of soil erosion control measures and highlighted implications for sustainable development in agriculture and environment in southeast, Nigeria. Purposive, multistage and random sampling techniques were employed in selecting a sample size of two hundred and forty (240) respondents. Structured interview schedule was used for data collection, while percentages, mean ratings and factor analysis techniques were employed for analysis. The findings show that majority (64.6%) of farmers were within the ages of 40-59, while majority (67.9%) had either FSLC or WASCE/SSCE/GCE/OL qualifications. The farmers reported that the major soil erosion control measures used were strip cropping (M = 4.8) and making of ridges against slopes (M = 4.7). The study reported that poor group affinity, inadequate institutional support and inadequate technical knowhow were constraints to soil erosion control in southeast, Nigeria. The study highlighted implications for sustainable development in agriculture and environment on organizational overhaul in extension, participatory extension policy on farmers groups and institutional re-orientation and synergy between Universities, Agricultural Development Programme (ADP), Ministry of Agriculture (MOA) and Local Government Councils. In conclusion, success in soil erosion control and sustainable development in agriculture and environment in southeast, Nigeria depends on the extent issues raised and implications highlighted can be addressed. The study recommends improved funding support to extension, participatory extension training and contacts with farmers' groups and groups' resources management. 展开更多
关键词 FARMERS erosion control sustainable development Nigeria.
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Development of a Multi KD~* P Controller
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作者 Y.D.Park 1, U.W.Nam 1, Y. J.Moon 1, H.Y.Kim 2 1 (Korea Astronomy Observatory, Taejon 305 348, KOREA) 2 (Department of Space Science in Kyunghee University, Seoul 449 701, KOREA) 《天文研究与技术》 CSCD 1999年第S1期109-113,共5页
We have developed a new multi KD *P controller which enables us to control the high voltage input and three KD *Ps power supply simultanenously for the Solar Flare Telescope (SOFT) in Bohyunsan Optical Astronomy Obser... We have developed a new multi KD *P controller which enables us to control the high voltage input and three KD *Ps power supply simultanenously for the Solar Flare Telescope (SOFT) in Bohyunsan Optical Astronomy Observatory (BOAO). The new KD *P controller permits a very short switching time as well as a stable of electric power supply, making it possible to obtain multiple frames in a single phase of high voltage. Here we have used a 80C196KC microprocessor and three high voltage modules. The rising and falling time of output pulses generated from the new controller is found to be less than 10 -3 sec and the power supply stability is maintained within accuracy of less than 0 1%. The period of a single phase voltage is controlled by user in the range of 0 03sec to 3 seconds. The number of integrated image frames is also set by user up to 256 frames. The present system can be readily utilized to control a wider range of high voltage power by simply modifying software. 展开更多
关键词 development of a Multi KD P controller
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