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Classification and technical target of water electrolysis for hydrogen production
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作者 Kahyun Ham Sooan Bae Jaeyoung Lee 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期554-576,I0012,共24页
Continuous efforts are underway to reduce carbon emissions worldwide in response to global climate change.Water electrolysis technology,in conjunction with renewable energy,is considered the most feasible hydrogen pro... Continuous efforts are underway to reduce carbon emissions worldwide in response to global climate change.Water electrolysis technology,in conjunction with renewable energy,is considered the most feasible hydrogen production technology based on the viable possibility of large-scale hydrogen production and the zero-carbon-emission nature of the process.However,for hydrogen produced via water electrolysis systems to be utilized in various fields in practice,the unit cost of hydrogen production must be reduced to$1/kg H_(2).To achieve this unit cost,technical targets for water electrolysis have been suggested regarding components in the system.In this paper,the types of water electrolysis systems and the limitations of water electrolysis system components are explained.We suggest guideline with recent trend for achieving this technical target and insights for the potential utilization of water electrolysis technology. 展开更多
关键词 Water electrolysis Hydrogen production technical target ELECTROCHEMISTRY
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Construction of a nomogram model to predict technical difficulty in performing laparoscopic sphincter-preserving radical resection for rectal cancer
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作者 Xiao-Cong Zhou Shi-Wei Guan +3 位作者 Fei-Yue Ke Gaurav Dhamija Qiang Wang Bang-Fei Chen 《World Journal of Gastroenterology》 SCIE CAS 2024年第18期2418-2439,共22页
BACKGROUND Colorectal surgeons are well aware that performing surgery for rectal cancer becomes more challenging in obese patients with narrow and deep pelvic cavities.Therefore,it is essential for colorectal surgeons... BACKGROUND Colorectal surgeons are well aware that performing surgery for rectal cancer becomes more challenging in obese patients with narrow and deep pelvic cavities.Therefore,it is essential for colorectal surgeons to have a comprehensive understanding of pelvic structure prior to surgery and anticipate potential surgical difficulties.AIM To evaluate predictive parameters for technical challenges encountered during laparoscopic radical sphincter-preserving surgery for rectal cancer.METHODS We retrospectively gathered data from 162 consecutive patients who underwent laparoscopic radical sphincterpreserving surgery for rectal cancer.Three-dimensional reconstruction of pelvic bone and soft tissue parameters was conducted using computed tomography(CT)scans.Operative difficulty was categorized as either high or low,and multivariate logistic regression analysis was employed to identify predictors of operative difficulty,ultimately creating a nomogram.RESULTS Out of 162 patients,21(13.0%)were classified in the high surgical difficulty group,while 141(87.0%)were in the low surgical difficulty group.Multivariate logistic regression analysis showed that the surgical approach using laparoscopic intersphincteric dissection,intraoperative preventive ostomy,and the sacrococcygeal distance were independent risk factors for highly difficult laparoscopic radical sphincter-sparing surgery for rectal cancer(P<0.05).Conversely,the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance was identified as a protective factor(P<0.05).A nomogram was subsequently constructed,demonstrating good predictive accuracy(C-index=0.834).CONCLUSION The surgical approach,intraoperative preventive ostomy,the sacrococcygeal distance,and the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance could help to predict the difficulty of laparoscopic radical sphincter-preserving surgery. 展开更多
关键词 NOMOGRAM Rectal cancer Laparoscopic operation Sphincter-preserving surgery technical difficulty
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Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems
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作者 Francis Levi A.DURANO Jon Marx SARMIENTO +1 位作者 Larry N.DIGAL Pedro A.ALVIOLA IV 《Journal of Mountain Science》 SCIE CSCD 2024年第1期33-48,共16页
Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa ... Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation areas. 展开更多
关键词 Cocoa farms Cobb-Douglas production function ELEVATION Philippines Stochastic frontier analysis technical efficiency
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Adhesion of Technical Lignin-Based Non-Isocyanate Polyurethane Adhesives for Wood Bonding
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作者 Jaewook Lee Byung-Dae Park Qinglin Wu 《Journal of Renewable Materials》 EI CAS 2024年第7期1187-1205,共19页
Lignin is the most abundant aromatic natural polymer,and receiving great attention in replacing various petro-leum-based polymers.The aim of this study is to investigate the feasibility of technical lignin as a polyol... Lignin is the most abundant aromatic natural polymer,and receiving great attention in replacing various petro-leum-based polymers.The aim of this study is to investigate the feasibility of technical lignin as a polyol for the synthesis of non-isocyanate polyurethane(NIPU)adhesives to substitute current polyurethane(PU)adhesives that have been synthesized with toxic isocyanate and polyols.Crude hardwood kraft lignin(C-HKL)was extracted from black liquor from a pulp mill followed by acetone fractionation to obtain acetone soluble-HKL(AS-HKL).Then,C-HKL,AS-HKL,and softwood sodium lignosulfonate(LS)were used for the synthesis of technical lignin-based NIPU adhesives through carbonation and polyamination and silane as a cross-linker.Their adhesion per-formance was determined for plywood.FTIR spectra showed the formation of urethane bonds and the reaction between lignin and silane.The NIPU adhesives prepared with C-HKL showed the highest adhesion strength among the three lignin-based NIPU adhesives.As the silane addition level increased,the adhesion strength of NIPU adhesives increased whereas formaldehyde emission decreased for all NIPU adhesives prepared.These results indicate that NIPU adhesives based on technical kraft lignin have a great potential as polyol for the synth-esis of bio-based NIPU adhesives for wood bonding. 展开更多
关键词 technical lignin non-isocyanate polyurethane wood adhesives adhesion strength formaldehyde emission
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Performance in the Fundamentals of Laparoscopic Surgery: Does it reflect global rating scales in the Objective Structured Assessment of Technical Skills in porcine laparoscopic surgery?
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作者 Ho Yee Tiong Wei Zheng So +10 位作者 Jeremy Yuen-Chun Teoh Shuji Isotani Gang Zhu Teng Aik Ong Eddie Shu-Yin Chan Peggy Sau-Kwan Chu Kittinut Kijvikai Ming Liu Bannakji Lojanapiwat Michael Wong Anthony Chi-Fai Ng 《Asian Journal of Urology》 CSCD 2024年第3期443-449,共7页
Objective:To correlate the utility of the Fundamentals of Laparoscopic Surgery(FLS)manual skills program with the Objective Structured Assessment of Technical Skills(OSATS)global rating scale in evaluating operative p... Objective:To correlate the utility of the Fundamentals of Laparoscopic Surgery(FLS)manual skills program with the Objective Structured Assessment of Technical Skills(OSATS)global rating scale in evaluating operative performance.Methods:The Asian Urological Surgery Training and Educational Group(AUSTEG)Laparoscopic Upper Tract Surgery Course implemented and validated the FLS program for its usage in laparoscopic surgical training.Delegates’basic laparoscopic skills were assessed using three different training models(peg transfer,precision cutting,and intra-corporeal suturing).They also performed live porcine laparoscopic surgery at the same workshop.Live surgery skills were assessed by blinded faculty using the OSATS rating scale.Results:From March 2016 to March 2019,a total of 81 certified urologists participated in the course,with a median of 5 years of post-residency experience.Although differences in task time did not reach statistical significance,those with more surgical experience were visibly faster at completing the peg transfer and intra-corporeal suturing FLS tasks.However,they took longer to complete the precision cutting task than participants with less experience.Overall OSATS scores correlated weakly with all three FLS tasks(peg transfer time:r=0.331,r^(2)=0.110;precision cutting time:r=0.240,r^(2)=0.058;suturing with intracorporeal knot time:r=0.451,r^(2)=0.203).Conclusion:FLS task parameters did not correlate strongly with OSATS globing rating scale performance.Although FLS task models demonstrated strong validity,it is important to assimilate the inconsistencies when benchmarking technical proficiency against real-life operative competence,as evaluated by FLS and OSATS,respectively. 展开更多
关键词 TheFundamentalsof Laparoscopic Surgery The Objective Structured Assessment of technical Skills Laparoscopic training Surgical education Surgical training Urological laparoscopic surgery
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Analysis of the Impact of Technical Trade Barriers on the Export of Toys-Based on Analysis of Zhejiang,China
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作者 LIU Ningning CHEN Xiaoxi 《Chinese Business Review》 2024年第1期37-46,共10页
Technical barriers to trade,as a non-tariff barrier,have an increasing impact on the international market.As a major province in toy exports,Zhejiang Province’s toy export trade is therefore greatly hindered.This art... Technical barriers to trade,as a non-tariff barrier,have an increasing impact on the international market.As a major province in toy exports,Zhejiang Province’s toy export trade is therefore greatly hindered.This article aims to explore the impact of technical trade barriers on toy exports in Zhejiang Province and analyze countermeasures.Through literature review and some empirical analysis,it is found that technical trade barriers have greatly promoted the development of Zhejiang’s toy industry;however,they have also subjected it to impacts and pressures such as cost and technology.In response to the impact of technical trade barriers on toy exports,this article proposes corresponding countermeasures to avoid such barriers:firstly,establish a quality management system that complies with export product regulations to ensure that the products produced can meet international requirements and standards;secondly,reduce dependence on overseas markets;then enhance one’s own technology,and strengthen product innovation,in order to enhance the international competitiveness of the product and oneself;in addition,we should also explore diversified markets and expand the sales channels and coverage of our products. 展开更多
关键词 technical trade barriers Zhejiang Province export of toys countermeasure analysis
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Analysis of Technical Intelligence of Tumor Cell Therapy Based on Patent Map
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作者 Liu Yue Zeng Yingying +1 位作者 Li Xue Yuan Hongmei 《Asian Journal of Social Pharmacy》 2024年第2期191-201,共11页
Objective To analyze the technical information in the field of tumor cell therapy in China,and to provide reference for identifying technical trends and predicting technical opportunities.Methods Based on the patent d... Objective To analyze the technical information in the field of tumor cell therapy in China,and to provide reference for identifying technical trends and predicting technical opportunities.Methods Based on the patent data in the field of tumor cell therapy in China,the patent map method was used to construct a scientific technical information analysis model.Then,the technical status of new drug research and development in this field was explored to identify technical opportunities.Results and Conclusion Studies have found that China’s tumor immunotherapy is in the growth stage.The technical innovation regions are mainly distributed in the east and innovative entities are enterprises.Technology hotspots are concentrated in areas such as A61P35,C12N5,and the patented technical efficacy is high.Besides,the technical research and development opportunities identified are closely related to the background in this field.To better promote the development of the industry,enterprises and research institutions should strengthen cooperation in technological innovation Meanwhile,they should pay attention to technical efficacy analysis to identify more technical opportunities,thereby effectively guiding innovation strategic decisions. 展开更多
关键词 patent map tumor immunotherapy technical intelligence analysis technical opportunity
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Analysis of the Gravity-1 Sea Launch System and Technical Features
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作者 ZHANG Tao HUANG Shuai +2 位作者 Ma Ma BU Xiangwei XU Guoguang 《Aerospace China》 2024年第1期18-27,共10页
Sea launch has the characteristics of flexible launching points, high landing area safety, and good economy. In recent years, it has become one of the important launch methods. Since 2019, China has carried out a tota... Sea launch has the characteristics of flexible launching points, high landing area safety, and good economy. In recent years, it has become one of the important launch methods. Since 2019, China has carried out a total of 11 successful sea launches. The Gravity-1(YL-1) sea launch system consists of a launch vehicle system and a sea launch platform. The sea launch program includes roll on/roll off boarding, sea mooring, sea maneuvering, anchoring and positioning, system testing, and formal launch. Through the maiden flight of YL-1, the design and manufacturing technology of large tonnage dedicated launch ship, launch vehicle vertical transfer and roll on/roll off boarding technology, anti-shake technology for sea launch, simple inflatable flexible insulation protective cover technology, and remote wireless measurement and control technology have been fully verified. 展开更多
关键词 YL-1 sea launch system technical features
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ISO Certification and Technical Efficiency in the Banking Sector:An Evidence from WAEMU’s Countries Using the DEA Method
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作者 Gnoleba Martin Zahore 《Economics World》 2024年第2期55-68,共14页
In the view of the international organization of standardization,the introduction of ISO standards is typical of quality management systems oriented towards strengthening the efficiency of enterprises.Business banks a... In the view of the international organization of standardization,the introduction of ISO standards is typical of quality management systems oriented towards strengthening the efficiency of enterprises.Business banks are not excluded from this requirement.The current study aims to evaluate the effect of ISO certification on the technical performance of WAEMU banks.Using BCEAO data(2020),the DEA model and Tobit estimates show that ISO certification has no effect on the efficiency scores of the banks in the sample.It is therefore appropriate for these banks to work on improving their business climate. 展开更多
关键词 business banks DEA technical efficiency ISO WAEMU TOBIT
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Study of The Technical Index of Online Learning Behavior Analysis of Nursing Majors on The Superstar Platform Based on The Kirkpatrick Evaluation Model
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作者 Yi Zhang Xiaohua Zhao Jie Li 《Journal of Clinical and Nursing Research》 2024年第4期284-291,共8页
Objective:To analyze the technical indexes of students’online learning behavior analysis based on Kirkman’s evaluation model,sort out the basic indexes of online learning behavior,and extract scientific and efficien... Objective:To analyze the technical indexes of students’online learning behavior analysis based on Kirkman’s evaluation model,sort out the basic indexes of online learning behavior,and extract scientific and efficient evaluation indexes of online learning effect through statistical analysis.Methods:The online learning behavior data of Physiology of nursing students from 2021-2023 and the first semester of 22 nursing classes(3 and 4)were collected and analyzed.The preset learning behavior indexes were analyzed by multi-dimensional analysis and a correlation analysis was conducted between the indexes and the final examination scores to screen for the dominant important indexes for online learning effect evaluation.Results:The study found that the demand for online learning of nursing students from 2021-2023 increased and the effect was statistically significant.Compared with the stage assessment results,the online learning effect was statistically significant.Conclusion:The main indicators for evaluating and classifying online learning behaviors were summarized.These two indicators can help teachers predict which part of students need learning intervention,optimize the teaching process,and help students improve their learning behavior and academic performance. 展开更多
关键词 Kirkpatrick assessment model Superstar platform Online learning behavior Analyzing technical indicators Research
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The Application of Reinforcement Theory in the Review Stage of English Teaching and Learning in Chinese Higher Vocational and Technical Colleges
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作者 Keren Pan 《Journal of Contemporary Educational Research》 2024年第8期88-94,共7页
Reinforcement theory is a behavioral psychology theory proposed by Skinner,which has been widely applied in various fields such as management and education.Positive reinforcement and negative reinforcement are the two... Reinforcement theory is a behavioral psychology theory proposed by Skinner,which has been widely applied in various fields such as management and education.Positive reinforcement and negative reinforcement are the two types of reinforcement.By adopting these two different reinforcement methods appropriately,human behavior can develop in a positive direction.In the review stage of English teaching and learning in Chinese higher vocational and technical colleges,the use of different reinforcement methods based on various classes,individuals,conditions,and environments can effectively promote or change the behavior of teachers and students,thereby improving the effectiveness of the review. 展开更多
关键词 Reinforcement theory Higher vocational and technical colleges English teaching and learning REVIEW EFFECTIVENESS
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Research on the Path of Cultivating High-Level Technical and Skilled Talents in Vocational Undergraduate Colleges and Universities
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作者 Kan Su Seong Pek Lim Linli Yao 《Journal of Contemporary Educational Research》 2024年第7期150-157,共8页
This paper explores strategies to cultivate high-level technical talents in vocational undergraduate colleges by analyzing their development,the essence of such talents,and proposing several key measures.Strategies in... This paper explores strategies to cultivate high-level technical talents in vocational undergraduate colleges by analyzing their development,the essence of such talents,and proposing several key measures.Strategies include optimizing professional settings and curricula,enhancing school-enterprise cooperation and the integration of industry-university-research,improving teaching staff quality and educational standards,and expanding international cooperation.The importance of policy support and funding and establishing robust quality assurance systems is emphasized for effectively cultivating skilled talents in vocational undergraduate colleges. 展开更多
关键词 Vocational undergraduate colleges High-level technical talents Professional setting Innovation and entrepreneurship education
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Discussion on the Application of Technical and Tactical Skills in Mixed Martial Arts Competitions
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作者 Yu Huang 《Journal of Contemporary Educational Research》 2024年第2期8-13,共6页
This article mainly analyzes the application of technical and tactical skills in mixed martial arts competitions,including mixed martial arts and its competition characteristics,the main application significance of te... This article mainly analyzes the application of technical and tactical skills in mixed martial arts competitions,including mixed martial arts and its competition characteristics,the main application significance of technical and tactical skills in mixed martial arts competitions,and its primary application strategies.It is hoped that this analysis can provide some guidelines for the appropriate application of mixed martial arts athletes’technical and tactical skills to improve their winning rate in mixed martial arts competitions. 展开更多
关键词 Mixed martial arts competition technical and tactical skills Fighting awareness Fighting movements Competition rhythm
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Analysis on Technical Structure and Competitiveness of ICT Manufacturing Industries
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作者 Xiaojie Tu Zhuofang Li +1 位作者 Minlin Wu Rongyi Yan 《China Communications》 SCIE CSCD 2023年第3期361-374,共14页
In order to analyze the technical structure and international comparative advantage of the information and communication technology(ICT)manufacturing industry,a complete set of ICT manufacturing product categories has... In order to analyze the technical structure and international comparative advantage of the information and communication technology(ICT)manufacturing industry,a complete set of ICT manufacturing product categories has been constructed by matching National Economical Industry Classification(GB/T4754-2017)with Harmonized System(HS)Codes,based on the relevant definitions in International Standard Industrial Classification(ISIC).The proposed definition overcomes inherent defects such as inaccurate scopes,lagging data and rough categories,which are characterized by commonly utilized product-level based classification approaches.Within the given framework,this paper has designed the technology content related indicators from the perspective of production distribution,and divided ICT product categories into high-end,medium-end and lowend manufacturing classifications according to respective global shares.Then,we have calculated international market shares(IMS),revealed comparative advantages(RCA),and market penetration rates(MPR)of ICT manufacturing exports for major economies from 2010 to 2021.Finally,development characterizations of ICT manufacturing industries for China’s Mainland are analyzed,and several practical suggestions are provided. 展开更多
关键词 ICT manufacturing industry technical
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Socio-Economic and Technical Characteristics of Beef Cattle Breeding in Ndé Division, West Region of Cameroon
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作者 David Fokom Wauffo Geraud C. Tasse Taboue +10 位作者 Brenda M. Tsana Nantia Gina France Djoumessi Tobou Elvis Ndukong Ndzi Abdou S. Nsangou Mohamed M. F. Ndebé Brice H. T. Fokouong Frank D. K. Wouembe Suzy G. Tsoupou Kuete Kingsley M. Tanyi Kingsley A. Etchu Fernand Tendongkeng 《Open Journal of Animal Sciences》 2023年第3期379-397,共19页
Insight is here provided into the socio-economic and technical characteristics of cattle production in the Ndé Division (West Cameroon region). Using a semi-structured questionnaire, information on the activity w... Insight is here provided into the socio-economic and technical characteristics of cattle production in the Ndé Division (West Cameroon region). Using a semi-structured questionnaire, information on the activity was assessed following onsite visits and interviewing breeders. Through a random sampling scheme, 110 breeders in the four subdivisions of the Ndé Division were shadowed. The majority (98.18%) of breeders were men aged 20 to 40 and married (91.82%). They belong to the Mbororo ethnic group, having cumulated more than 10 years in the activity. Most respondents (50.91%) did not attend school and earn their living mainly from livestock (78.18%). Cattle were raised for sale and to feed the breeder’s family (77.27%). The main mode of acquisition of animals was through inheritance (81.82%). The cattle breeds were mostly made up of white Fulani (70%), living in private farms using a combination of stake and barbed wires (67.27%) as fences. The combination of natural fodder and cooking salt was used by most breeders (59.09%) as a daily ration. Reproduction was by natural mating (97.07%). Parasites (internal and external) and foot-and-mouth disease were the main diseases reported by the majority of farmers. Self-treatment (50%) was the main prophylactic measure taken by farmers in case of disease symptoms. Cattle herders faced several challenges, such as insufficient pasture (67.27%), agro-pastoral conflicts (76.36%) and diseases (90.91%). Cattle breeding was rather a widespread activity with no particular restriction. 展开更多
关键词 Cattle Breeding SOCIO-ECONOMIC BREEDING technical Characteristics CONSTRAINTS Cameroon
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Myth and Digital Fantasy from the Perspective of Technical Aesthetics
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作者 TIAN Miaozi LU Wuyun 《Journal of Landscape Research》 2023年第2期85-88,92,共5页
The surreal space of digital technology development has created an unprecedented utopian mythological world.The virtual reality research started in the 1960s has gradually become a reality with the support of hardware... The surreal space of digital technology development has created an unprecedented utopian mythological world.The virtual reality research started in the 1960s has gradually become a reality with the support of hardware technology.The media mode of observing the world by simulating human eyes with cameras is being replaced by computer simulation technology.The metaverse global vision based on virtual space and sense of time obscures the traditional perspective,and a novel progressive aesthetic category gradual y emerges.Starting with the aesthetic experience of myth brought by digital technology,this paper reviews the history of myth and analyzes the mental image of myth and religion to push the origin of life to a more profound realm.The contemporary“myth”following technological development changes the situation of human cognition of the world,separates the myth from the historical frame and relates it to the contemporary ongoing. 展开更多
关键词 technical aesthetics Metaverse Digital fantasy MYTH Artificial intelligence
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Technical Efficiency of"Master Switch"in Widening the Human Living Space by Fenlong Tillage
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作者 Benhui WEI 《Asian Agricultural Research》 2023年第1期1-3,共3页
This paper reports"the fourth set"of drilling tillage after"ploughing(hoeing)"by manpower,animal power and tractor——Fenlong tillage technology(referred to as"Fenlong technology").It mak... This paper reports"the fourth set"of drilling tillage after"ploughing(hoeing)"by manpower,animal power and tractor——Fenlong tillage technology(referred to as"Fenlong technology").It makes the cultivated land and saline alkali land transformed into"sponge"farmland through"drill bit"vertically digging into the soil,one-time deep cultivation,not disturbing soil layer,and granulating the soil,to bring about the effects of"expanding the land,releasing the natural force,water conservation,disaster reduction,carbon reduction,tillage saving,fertilizer saving and grain increasing",and can broaden the space for human survival and development.It has been applied to more than 50 crops in 28 provinces,including Guangxi,Hebei and Tibet.Without increasing the use of fertilizer and water,the yield of varieties in cultivated land increased by 10%-50%,while that in saline and alkaline land increased by 20%-100%.The storage of natural precipitation increased by 100%,and drought,high temperature and low temperature decreased by 20%-30%,and carbon sequestration and emission reduction reached 20%.It is proposed that China can implement the"dual strategy"platform of farmland,saline alkali land,rivers and water bodies constructing the"incremental""five new warehouses"of grain,water,fish,sugar,etc.and"increased grain return"abroad,to ensure national security. 展开更多
关键词 Fenlong tillage technology Living space Five new warehouses technical efficiency
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The Impact of Fabric Weave and Anisotropy on the Poisson’s Ratio in Technical Fabrics
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作者 DianaŠimićPenava Željko Penava Tea Jovanović 《Journal of Civil Engineering and Architecture》 2023年第8期373-389,共17页
Poisson’s ratio changes during the tensile stress of technical fabric samples due to the anisotropy of technical fabrics.This paper examines the effects of the type of weave and the anisotropic characteristics of the... Poisson’s ratio changes during the tensile stress of technical fabric samples due to the anisotropy of technical fabrics.This paper examines the effects of the type of weave and the anisotropic characteristics of the technical fabric on maximum tensile force,corresponding elongation,work-to-maximum force,elasticity modulus,and Poisson’s ratio when axial tensile forces are applied to samples cut at various angles in the direction of the weft yarns of the technical fabric.In the lab,3 cotton fabric samples of constant warp and weft density with different structural weave types(plain weave,twill weave,atlas weave)were subjected to the tensile force until they broke at the following angles:0°,15°,30°,45°,60°,75°,90°.Based on the different measured values of technical fabric stretching in the longitudinal direction and lateral narrowing,Poisson’s ratio is calculated.The Poisson’s ratio was calculated up to a relative elongation of the fabric of 8%,as the buckling of the fabric occurs according to this elongation value.According to the results presented in this paper,the type of weave of the fabric,the direction of tensile force,and the relative narrowing of the technical fabrics all play important roles in the Poisson’s ratio value.The Poisson’s ratio curve of a technical fabric under tensile stress(i.e.elongation)is primarily determined by its behaviour in the opposite direction of the elongation.The change in the value of the Poisson’s ratio is represented by a graph that first increases nonlinearly and then decreases after reaching its maximum value. 展开更多
关键词 WARP WEFT technical fabric weave type Poisson’s ratio tensile force
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Measuring technical efficiency of Chinese nonferrous metals enterprises on a background of industry consolidation 被引量:5
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作者 危平 唐慧泉 +1 位作者 陈瑶 陈晓红 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第9期2797-2806,共10页
Since 2009, Chinese nonferrous metals industry has been carried out industry consolidation with strong support by the central government. This work examined technical efficiency of Chinese nonferrous metals firms and ... Since 2009, Chinese nonferrous metals industry has been carried out industry consolidation with strong support by the central government. This work examined technical efficiency of Chinese nonferrous metals firms and its change during the period of 2007 and 2011. Based on financial data from nonferrous metals listed companies, technical efficiency of nonferrous metal minerals mining firms and nonferrous metal smelting, pressing and processing firms was estimated respectively using the data envelopment analysis (DEA) method. It was found that, in both sectors, number of pure technical and scale inefficient firms dominated over efficient ones. Overall, their technical and scale efficiency tended to be very low after 2009. In particular, efficiency scores of nonferrous metal smelting, pressing and processing firms fluctuated greatly during the research period. And a limited number of large leading firms were able to maintain 100% efficiency score in the industry, while efficiency of most of other leading firms has declined since 2009. 展开更多
关键词 industry consolidation nonferrous metals finns data envelopment analysis (DEA) technical efficiency scale efficiency CONGLOMERATE
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MODEL OF FLIGHT TECHNICAL ERROR IN SYMMETRICAL PLANE FOR PERFORMANCE BASED NAVIGATION 被引量:2
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作者 赵鸿盛 徐肖豪 +2 位作者 张军 朱衍波 杨传森 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第3期246-254,共9页
In the performance based navigation(PBN),the flight technical error(FTE)and the navigation system error(NSE)are two main parts of total system error(TSE).The implementation of PBN requires pre-flight predictio... In the performance based navigation(PBN),the flight technical error(FTE)and the navigation system error(NSE)are two main parts of total system error(TSE).The implementation of PBN requires pre-flight prediction and en-route short-term dynamical prediction of TSE.Once the sum of predicted FTE and NSE is greater than the specified PBN value,PBN cannot operate.Thus,it requires accurate modeling and thorough analysis of the two main contributors.Multiple-input multiple-output(MIMO)longitudinal flight control system of ARIC model is designed using the linear quadratic Gaussian and loop transfer recovery(LQG/LTR)method,and FTE in symmetrical plane of aircraft is analyzed during the turbulence disturbed approach.The error estimation mapping function of FTE in symmetrical plane and its bound estimation model are proposed based on the singular value theory.The model provides an approach based on the forming mechanism of FTE,rather than the costly flight test and the data fitting.Real-data based simulation validates the theoretical analysis of FTE in symmetrical plane.It also shows that FTE is partially caused by the turbulence fluctuation disturbance when the automatic flight control system(AFCS)is engaged and increases with escalating the environmental turbulence intensity. 展开更多
关键词 flight technical error performance based navigation LQG/LTR air traffic management Kalman filter
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