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Experimental Investigation of Laser Surface Hardening of AISI 4340 Steel Using Different Laser Scanning Patterns 被引量:1
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作者 Baha Tarchoun Abderrazak El Ouafi Ahmed Chebak 《Journal of Minerals and Materials Characterization and Engineering》 2020年第2期9-26,共18页
Laser surface transformation hardening becomes one of the most modern processes used to improve fatigue and wear properties of steel surfaces. In this process, the material properties and the heating parameters are th... Laser surface transformation hardening becomes one of the most modern processes used to improve fatigue and wear properties of steel surfaces. In this process, the material properties and the heating parameters are the factors that present the most significant effects on the hardened surface attributes. The control of these factors using predictive modeling approaches to achieve desired surface properties leads to conclusive results. However, when the dimensions of the surface to be treated are larger than the cross-section of the laser beam, various laser-scanning patterns are involved. This paper presents an experimental investigation of laser surface hardening of AISI 4340 steel using different laser scanning patterns. This investigation is based on a structured experimental design using the Taguchi method and improved statistical analysis tools. Experiments are carried out using a 3 kW Nd: YAG laser source in order to evaluate the effects of the heating parameters and patterns design parameters on the physical and geometrical characteristics of the hardened surface. Laser power, scanning speed and scanning patterns (linear, sinusoidal, triangular and trochoid) are the factors used to evaluate the hardened depth and the hardened width variations and to identify the possible relationship between these factors and the hardened zone attributes. Various statistical tools such as ANOVA, correlations analysis and response surfaces are applied in order to examine the effects of the experimental factors on the hardened surface characteristics. The results reveal that the scanning patterns do not modify the nature of the laser parameters’ effects on the hardened depth and the hardened width. But they can accentuate or reduce these effects depending on the type of the considered pattern. The results show also that the sinusoidal and the triangular patterns are relevant when a maximum hardened width with an acceptable hardened depth is desired. 展开更多
关键词 LASER Surface HARDENING Process Experimental Investigation LASER Scanning patternS AISI 4340 STEEL Hardness Profile Hardened Depth Hardened WIDTH Design of Experiment Analysis of Variance
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Pattern of disharmony between the heart and kidney: Theoretical basis, identification and treatment
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作者 Jian Dong Tianfang Wang +1 位作者 Lihong Zhao Xinran Chen 《Journal of Traditional Chinese Medical Sciences》 2017年第4期317-321,共5页
'Harmony between the heart and kidney' refers to the physiological relationship between these two zang organs in Chinese medicine,while 'disharmony between the heart and kidney' (also called disharmony... 'Harmony between the heart and kidney' refers to the physiological relationship between these two zang organs in Chinese medicine,while 'disharmony between the heart and kidney' (also called disharmony between fire and water) refers to the pathological state.The pattern of disharmony between the heart and kidney is widely observed in patients with insomnia,anxiety disorder and menopausal syndrome,etc..In order to gain a full and systematical understanding of this pattern,from the perspective of ancient Chinese philosophy and zang-fu theory in Chinese medicine,we systematically reviewed and discussed the functions and physiological characteristics of the heart and kidney,the origin and development of theories relating to heart-kidney relationship,the pathogenesis and identification of the pattern,as well as the commonly used classical formulas for its treatment,including Coptis and DonkeyHide Gelatin Decoction (Huánglián (E)jiāo Tāng) and Grand Communication Pill (Jiāotài Wán).Two examples of clinical modifications of these formulas in the treatment of insomnia and menopausal syndrome are provided in this article.It should be noted that in clinical practice,these formulas should be used flexibly,and modified in accordance to the condition of the patient. 展开更多
关键词 Harmony BETWEEN the HEART and KIDNEY Disharmony BETWEEN the HEART and KIDNEY pattern of disharmony BETWEEN the HEART and KIDNEY Coptis and Donkey-Hide Gelatin Decoction (Huánglián (E)jiāo Tāng) Grand Communication Pill (Jiāotài Wán)
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Quantifying the vertical distribution pattern of land-use conversion in the loess hilly region of northern Shaanxi Province 1995–2015 被引量:4
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作者 曹智 李裕瑞 +1 位作者 刘正佳 杨凌帆 《Journal of Geographical Sciences》 SCIE CSCD 2019年第5期730-748,共19页
The mountainous and hilly region plays an important role in ecological safety and production in China. However, recent studies have poorly characterized the parallel structure of land use in the valleys of the mountai... The mountainous and hilly region plays an important role in ecological safety and production in China. However, recent studies have poorly characterized the parallel structure of land use in the valleys of the mountainous and hilly region using topographic factors(e.g.elevation, slope, aspect). Here, the loess hilly region of northern Shaanxi Province is used as a representative case area to analyze the vertical distribution pattern of land-use conversion using the relative elevation concept and the HAND index. The differences in the vertical structure of land-use conversion between absolute elevation and relative elevation were compared. We found that the classifications of absolute and relative elevation had similar proportions of each relative elevation grade in each absolute elevation grade. Cropland,woodland, and grassland were distributed evenly in each grade of absolute/relative elevation,while water body, built-up land and unused land were more likely to spread in low grades of relative elevation than those of absolute elevation. The land-use conversion(i.e. loss of cropland and gain in woodland and built-up land) showed an apparently stepped distribution with relative elevation classification, suitable for revealing vertical distributions of land-use conversion in the loess hilly region. Cropland transformed to woodland was mainly distributed in high grade of relative elevation, decreasing with a decrease in grades, while built-up land transformed from cropland and grassland was mainly distributed in low grade of relative elevation, decreasing with increases in grades. The grade of relative elevation where cropland transformed to woodland descended with the implementation of the Grain for Green Project. Our results suggest that it is better to analyze the vertical distribution of land-use conversion with relative elevation classification in hilly regions. 展开更多
关键词 land use change VERTICAL distribution pattern topographic factors HAND(Height ABOVE the Nearest Drainage) LOESS HILLY region northern SHAANXI PROVINCE
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Human dermal reticular fibroblasts at confluence display a signature micro pattern <i>in vitro</i>
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作者 Denis E. Solomon 《Open Journal of Regenerative Medicine》 2013年第4期99-105,共7页
This paper sets out to demonstrate that scraping of the flat dorsal surface of human dermis with a scalpel blade and cell plating without centrifugation can lead to the recognition and identification of the individual... This paper sets out to demonstrate that scraping of the flat dorsal surface of human dermis with a scalpel blade and cell plating without centrifugation can lead to the recognition and identification of the individual packing micro pattern of dermal reticular fibroblasts at confluence. The characteristic alignment of papillary and reticular fibroblasts at right angles to each other led to the positive identification of reticular fibroblasts. A non-enzymatic means of sub-culturing (passaging), which yields fully functional, healthy cells with normal, phenotypic morphology is also described. Implications for published subcutaneous wound healing studies are discussed as well as the confluent reticular fibroblast configuration, interpreted as ananatomic site identity code,which may be the address of a specific fibroblast gene pattern expression. 展开更多
关键词 Papillary and RETICULAR FIBROBLASTS Cell Culture of HUMAN DERMAL FIBROBLASTS DERMAL Filler DERMAL RETICULAR Fibroblast Micro pattern Wound Healing Anatomic Site Identity Code
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Antibiotic sensitivity pattern of bacterial pathogens in the intensive care unit of Fatmawati Hospital,Indonesia 被引量:7
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作者 Maksum Radji Siti Fauziah Nurgani Aribinuko 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2011年第1期39-42,共4页
Objective:To evaluate the sensitivity pattern of bacterial pathogens in the intensive care unit(ICU) of a tertiary care of Falmawati Hospital Jakarta Indonesia.Methods:A cross sectional retrospective study of bacteria... Objective:To evaluate the sensitivity pattern of bacterial pathogens in the intensive care unit(ICU) of a tertiary care of Falmawati Hospital Jakarta Indonesia.Methods:A cross sectional retrospective study of bacterial pathogen was carried out on a total of 722 patients that were admitted to the ICU of Fatmawati Hospital Jakarta Indonesia during January 2009 to March 2010. All bacteria were identified by standard microbiologic methods,and(heir antibiotic susceptibility testing was performed using disk diffusion method.Results:Specimens were collected from 385 patients who were given antimicrobial treatment,of which 249(64.68%) were cultured positive and 136(35.32%) were negative.The most predominant isolate was Pseudomonas aeruginosa(P.aeruginosa)(26.5%) followed by Klebsiella pneumoniae(K.pneumoniae)(15.3%) and Staphylococcus epidermidis(14.9%).P.aeruginosa isolates showed high rate of resistance to cephalexin(95.3%),cefotaxime(64.1%),and ceftriaxone(60.9%).Amikacin was the most effective(84.4%) antibiotic against P.aeruginosa followed by imipenem(81.2%),and meropenem(75.0%).K.pneumoniae showed resistance to cephalexin(86.5%),ceftriaxone(75.7%),ceftazidime(73.0%),cefpirome(73.0%) and cefotaxime(67.9%),respectively.Conclusions:Most bacteria isolated from ICU of Fatmawati Hospital Jakarta Indonesia were resistant to the third generation of cephalosporins,and quinolone antibiotics.Regular surveillance of antibiotic susceptibility pallerns is very important for setting orders to guide the clinician in choosing empirical or directed therapy of infected patients. 展开更多
关键词 Antibiotic susceptibility Intensive care unit BACTERIAL RESISTANCE BACTERIAL pathogen Sensitivity pattern Antimicrobial RESISTANCE Pseudomonas AERUGINOSA KLEBSIELLA PNEUMONIAE Isolate Specimen
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Remaining Oil Distribution Law and Potential Tapping Strategy of Horizontal Well Pattern in Narrow Oil Rim Reservoir with Gas Cap and Edge Water
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作者 Xiaolin Zhu Zongbin Liu +2 位作者 Xinran Wang Zhiqiang Meng Qin Zhu 《World Journal of Engineering and Technology》 2019年第3期355-364,共10页
For thin oil rim reservoir with gas cap and edge water, it is helpful to improve the development effect to find out the distribution law of remaining oil in this kind of reservoirs. For this reason, taking the narrow ... For thin oil rim reservoir with gas cap and edge water, it is helpful to improve the development effect to find out the distribution law of remaining oil in this kind of reservoirs. For this reason, taking the narrow oil rim reservoir with gas cap and edge water of Oilfield A in Bohai Sea as a case, the main controlling factors, including reservoir structure, fault, gas cap energy, edge water energy and well pattern, affecting the distribution of residual oil in this kind of reservoir were analyzed by using the data of core, logging, paleogeomorphology and production. Then, the distribution law of remaining oil was summarized. Generally, the remaining oil distribution is mainly potato-shaped or strip-shaped in plane. Vertically, it depends on the energy of gas cap and edge water. For the reservoir with big gas gap and weak edge water, the remaining oil mainly lies in the bottom of oil column. And for the reservoir with small gas gap and strong edge water, the remaining oil mainly locates at the top of oil column. Aiming at different distribution modes of remaining oil, the corresponding potential tapping strategies of horizontal wells are put forward: in the late stage of development, for the reservoir with big gas gap and weak edge water, the remaining oil concentrates at the bottom of the oil column, and the position of horizontal well should be placed at the lower 1/3 to the lower 1/5 of the oil column;for the reservoir with small gas cap and strong edge water, the remaining oil locates at the top of the oil column, and the position of horizontal well should be put at the upper 1/5 to the upper 1/3 of the oil column height, vertically. Based on the study on remaining oil of Oilfield A, a potential tapping strategy of well pattern thickening and vertical position optimization of horizontal well was proposed. This strategy guided the efficient implementation of the comprehensive adjustment plan of the oilfield. Moreover, 18 infill development wells were implemented in Oilfield A, and the average production of the infill wells is 2.1 times that of the surrounding old wells. It is estimated that the ultimate recovery factor of the oilfield will reach 33.9%, which is 2.3% higher than that before infilling wells. This study can be used for reference in the development of similar reservoirs. 展开更多
关键词 Thin OIL RIM RESERVOIR with Gas Cap and Edge Water Horizontal WELL pattern Remaining OIL Vertical Position Optimization WELL pattern THICKENING
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Integration of InVEST-habitat quality model with landscape pattern indexes to assess mountain plant biodiversity change: A case study of Bailongjiang watershed in Gansu Province 被引量:47
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作者 GONG Jie XIE Yuchu +2 位作者 CAO Erjia Huang Qiuyan LI Hongying 《Journal of Geographical Sciences》 SCIE CSCD 2019年第7期1193-1210,共18页
Mountains in western China, hosted rich biodiversity and millions of people and inhabitant with vital ecosystem services, had experienced the most serious biodiversity loss with fragile ecological problems. Even thoug... Mountains in western China, hosted rich biodiversity and millions of people and inhabitant with vital ecosystem services, had experienced the most serious biodiversity loss with fragile ecological problems. Even though increasing attentions had been paid to this issue, we still lacked efficient methods to assess the change of plant biodiversity at medium/large scale due to the poor data and co-existing multiple habitat types. This study proposed an integrated method combining InVEST-habitat quality model, NPP and landscape pattern indexes to analyze the spatial heterogeneity of plant biodiversity and its spatiotemporal change on raster cell scale. The results indicated that plant biodiversity service was high in Bailongjiang watershed with obvious spatial pattern variations. The land area containing higher plant biodiversity were 3161 km2, which mainly distributed in the National Nature Reserve and forestry area. While the areas with lower plant biodiversity accounted for 37.67% and mainly distributed in the valleys between Zhouqu-Wudu-Wenxian County, the valley of Minjiang in Tanchang County and alpine mountain snow-covered regions. During 1990–2010, plant biodiversity level tended to increase and the higher plant biodiversity area increased from 14.13% to 17.15% due to ecological restoration and afforestation, while plant biodiversity decreased in the area with intensive human activities, such as cultivated land, urban and rural land. The results showed that combining InVEST-habitat quality model, NPP and landscape pattern indexes can effective reveal mountain plant biodiversity change. The study was useful for plant biodiversity conservation policy-making and human activity management for the disaster-impacted mountainous areas in China. 展开更多
关键词 spatial CHANGE HABITAT quality landscape pattern plant BIODIVERSITY conservation: INVEST model Bailongjiang WATERSHED in GANSU Province
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A quantitative evaluation for well pattern adaptability in ultra-low permeability oil reservoirs:A case study of Triassic Chang 6 and Chang 8 reservoirs in Ordos Basin 被引量:1
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作者 ZHAO Jiyong AN Xiaoping +4 位作者 WANG Jing FAN Jianming KANG Xingmei TAN Xiqun LI Wenqing 《Petroleum Exploration and Development》 2018年第3期499-506,共8页
Based on the previous studies and development practice in recent 10 years, a quantitative evaluation method for the adaptability of well patterns to ultra-low permeability reservoirs was established using cluster anal... Based on the previous studies and development practice in recent 10 years, a quantitative evaluation method for the adaptability of well patterns to ultra-low permeability reservoirs was established using cluster analysis and gray correlation method, and it includes 10 evaluation parameters in the four aspects of optimal evaluation parameters, determination of weights for evaluation parameters, development stage division, and determination of classification coefficients. This evaluation method was used to evaluate the well pattern adaptability of 13 main ultra-low permeability reservoirs in Triassic Chang 6 and Chang 8 of Ordos Basin. Three basic understandings were obtained: Firstly, the well pattern for ultra-low permeability type-I reservoirs has generally good adaptability, with proper well pattern forms and well pattern parameters. Secondly, square inverted nine-spot well pattern is suitable for reservoirs with no fractures; rhombic inverted nine-spot injection pattern is suitable for reservoirs with some fractures; and rectangular well pattern is suitable for reservoirs with rich fractures. Thirdly, for the ultra-low permeability type-Ⅱ and type-Ⅲ reservoirs, with the principles of well pattern form determination, the row spacing needs to be optimized further to improve the level of development of such reservoirs. 展开更多
关键词 ultra-low permeability oil reservoir well pattern adaptability comprehensive evaluation parameter ORDOS Basin TRIASSIC CHANG 6 FORMATION CHANG 8 FORMATION
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Identification of SNPs and expression patterns of FZD3 gene and its effect on wool traits in Chinese Merino sheep(Xinjiang Type) 被引量:4
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作者 ZHAO Bing-ru FU Xue-feng +9 位作者 TIAN Ke-chuan HUANG Xi-xia DI Jiang BAI Yan XU Xin-ming TIAN Yue-zhen WU Wei-wei ABLAT Sulayman ZENG Wei-dan HANIKEZI Tulafu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第10期2351-2360,共10页
As a member of the Frizzled family, Frizzled3 (FZD3) is a receptor of the canonical Wnt signaling pathway and plays a vital role in mammalian hair follicle developmental processes. However, its effects on wool traits ... As a member of the Frizzled family, Frizzled3 (FZD3) is a receptor of the canonical Wnt signaling pathway and plays a vital role in mammalian hair follicle developmental processes. However, its effects on wool traits are not clear. The objectives of this study were to identify the single nucleotide polymorphisms (SNPs) and the expression patterns of FZD3 gene, and then to determine whether it affected wool traits of Chinese Merino sheep (Xinjiang Type) or not. PCR-single stranded conformational polymorphism (PCR-SSCP) and sequencing were used to identify mutation loci, and general linear model (GLM) with SAS 9.1 was used for the association analysis between wool traits and SNPs. Quantitative real-time PCR (qRT-PCR) was used to investigate FZD3 gene expression levels. The results showed that six exons of FZD3 gene were amplified and two mutation loci were identified in exon 1 (NC_019459.2: g.101771685 T>C (SNP1)) and exon 3 (NC_019459.2: g.101810848, A>C (SNP2)), respectively. Association analysis showed that SNP1 was significantly associated with mean fiber diameter (MFD)(P=0.04) and live weight (LW)(P=0.0004), SNP2 was significantly associated with greasy fleece weight (GFW)(P=0.04). The expression level of FZD3 gene in skin tissues of the superfine wool (SF) group was significantly lower (P<0.05) than that of the fine wool (F) group. Moreover, it had a higher expression level (P<0.01) in skin tissues than in other tissues of Chinese Merino ewes. While, its expression level had a fluctuant expression in skin tissues at different developmental stages of embryos and born lambs, with the highest expression levels (P<0.01) at the 65th day of embryos. Our study revealed the genetic relationship between FZD3 variants and wool traits and two identified SNPs might serve as potential and valuable genetic markers for sheep breeding and lay a molecular genetic foundation for sheep marker-assisted selection (MAS). 展开更多
关键词 Chinese MERINO SHEEP (Xinjiang Type) FZD3 single NUCLEOTIDE polymorphism (SNP) expression pattern association analysis WOOL TRAITS
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Patterns in Heuristic Optimization Algorithms: A Comprehensive Analysis
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作者 Robertas Damasevicius 《Computers, Materials & Continua》 2025年第2期1493-1538,共46页
Heuristic optimization algorithms have been widely used in solving complex optimization problems in various fields such as engineering,economics,and computer science.These algorithms are designed to find high-quality ... Heuristic optimization algorithms have been widely used in solving complex optimization problems in various fields such as engineering,economics,and computer science.These algorithms are designed to find high-quality solutions efficiently by balancing exploration of the search space and exploitation of promising solutions.While heuristic optimization algorithms vary in their specific details,they often exhibit common patterns that are essential to their effectiveness.This paper aims to analyze and explore common patterns in heuristic optimization algorithms.Through a comprehensive review of the literature,we identify the patterns that are commonly observed in these algorithms,including initialization,local search,diversity maintenance,adaptation,and stochasticity.For each pattern,we describe the motivation behind it,its implementation,and its impact on the search process.To demonstrate the utility of our analysis,we identify these patterns in multiple heuristic optimization algorithms.For each case study,we analyze how the patterns are implemented in the algorithm and how they contribute to its performance.Through these case studies,we show how our analysis can be used to understand the behavior of heuristic optimization algorithms and guide the design of new algorithms.Our analysis reveals that patterns in heuristic optimization algorithms are essential to their effectiveness.By understanding and incorporating these patterns into the design of new algorithms,researchers can develop more efficient and effective optimization algorithms. 展开更多
关键词 Heuristic optimization algorithms design patterns INITIALIZATION local search diversity maintenance ADAPTATION STOCHASTICITY exploration EXPLOITATION search space metaheuristics
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Experiments on the influences of well pattern on water flooding characteristics of dissolution vug-cave reservoir
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作者 WANG Jing LIU Huiqing +4 位作者 ZHANG Jing ZHAO Wei HUANG Yitao KANG Zhijiang ZHENG Songqing 《Petroleum Exploration and Development》 2018年第6期1103-1111,共9页
Based on the similarity criterion, volcanic rock samples were taken from outcrops to make experimental models. Water flooding experiments of five-spot well pattern, nine-spot well pattern, five-spot to nine-spot well ... Based on the similarity criterion, volcanic rock samples were taken from outcrops to make experimental models. Water flooding experiments of five-spot well pattern, nine-spot well pattern, five-spot to nine-spot well pattern, the relationship between relative well and fracture positions, and injection rate in dissolution vug-cave reservoirs with/without fractures were carried out to analyze variation regularities of development indexes, find out development characteristics of water flooding with different well patterns and sort out the optimal water flooding development mode. For dissolution vug-cave reservoirs without fractures, five-spot well pattern waterflooding has very small sweeping area, serious water channeling and low oil recovery. When the well pattern was adjusted from five-spot to nine-spot well pattern, oil recovery could be largely improved, but the corner well far from the injector is little affected. In dissolution vug-cave reservoirs with fractures, when the injector and producer are not connected by fractures, the fractures could effectively connect the poorly linked vugs to improve the development effect of water flooding. Whether there are fractures or not in dissolution vug-cave reservoirs, the development effect of nine-spot well-pattern is much better than that of five-spot well pattern and five-spot to nine-spot well pattern, this is more evident when there are fractures, and the edge well has better development indexes than corner well. At the high-water cut stage of water flooding with nine-spot well pattern, the oil recovery can be further improved with staggered line-drive pattern by converting the corner well into injection well. It is helpful to increase the oil production of corner well of nine-spot well pattern by increasing the injection rate, and improve ultimate oil recovery, but the water-free production period would be greatly shortened and water-free recovery would decrease. 展开更多
关键词 similarity criterion DISSOLUTION vug-cave RESERVOIR water FLOODING injection-production WELL pattern WELL placement INJECTION rate development index oil recovery
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Computer-aided Pattern Design of Multi-bar Warp Knitted Fabrics
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作者 李炜 《Journal of China Textile University(English Edition)》 EI CAS 2000年第1期85-87,共3页
To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the ... To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the computer-aided pattern design of multi-barwarp knitted fabrics.In terms of the special propertiesof the computer-aided pattern design of multi-barwarp knitted fabrics,the Object Oriented Program(OOP)programming-Object Windows class Library(OWL)programming is selected.According to thecharacters of the OWL programming,various functionsare defined.Pattern design and technical parameters canbe output,which offers a great convenience for the fac-tory. 展开更多
关键词 MULTI - bar WARP KNITTED fabric computer -aided pattern design pattern Object Windows class Library (OWL) programming.
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Quantitative division of succession and spatial patterns among different stand developmental stages in Changbai Mountains 被引量:2
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作者 GONG Zhi-wen KANG Xin-gang GU Li 《Journal of Mountain Science》 SCIE CSCD 2019年第9期2063-2078,共16页
Broadleaf-Korean pine forests exhibit high species richness and distinctive species composition, which are currently becoming more dominant among natural forests in Changbai Mountains of northeastern China. Understand... Broadleaf-Korean pine forests exhibit high species richness and distinctive species composition, which are currently becoming more dominant among natural forests in Changbai Mountains of northeastern China. Understanding the ecological process of restored vegetation is quite important for ecosystem reconstruction. Distinguishing stand development stages and analyzing the dynamic spatial patterns could provide insights into significant community coexistence mechanisms. In the present study, eight permanent study areas were established according to the substituting space for time method in Changbai Mountains of north-eastern China. The optimal division method was used to quantify the successional series into different stand development stages, and the point pattern analysis method(L(r) function) was used to analyse the dynamic changes in spatial patterns and interspecific associations. Our results suggested that:(1) The stand development process was divided into five stages: the first three stages were poplar-birch secondary forests in different stages of recovery, the fourth stage was thespruce-fir mixed forest, and the last stage was the primary broadleaf-Korean pine forest;(2) The spatial pattern showed an aggregated distribution at a small scale and changed to a random distribution as the scale increased in poplar-birch secondary forests, but the spatial pattern appeared to be randomly distributed in spruce-fir mixed forest and broadleafKorean pine forest;(3) The interspecific associations between pioneer species and climax species changed from negative to positive among the different stand stages, and environmental resources were shared among these species. Interspecific differences in shade tolerance among the tree species were key determinants of forest dynamics and structure. Our study is vital to the understanding of the forest development;thus, the spatial change features should receive greater attention when forest management is being planned and restoration strategies are being developed for the Changbai Mountains. 展开更多
关键词 Dynamic spatial patterns INTERSPECIFIC association Optimal DIVISION method STAND DEVELOPMENTAL STAGES Space for time substitution
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Assessing the influence of the minimum measured diameter on forest spatial patterns and nearest neighborhood relationships 被引量:2
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作者 LI Yuan-fa YANG Hai-peng +2 位作者 WANG Hong-xiang YE Shao-ming LIU Wen-zhen 《Journal of Mountain Science》 SCIE CSCD 2019年第10期2308-2319,共12页
Forest structure analysis is important for understanding the properties and development of a forest community,and its outcomes can be influenced by how trees are measured in sampled plots.Although there is a general c... Forest structure analysis is important for understanding the properties and development of a forest community,and its outcomes can be influenced by how trees are measured in sampled plots.Although there is a general consensus on the height at which tree diameter should be measured[1.3 m:diameter at breast height(DBH)],the minimum measureddiameter(MMD)often varies in different studies.In this study,we assumed that the outcomes of forest structure analysis can be influenced by MMD and,to this end,we applied g(r)function and stand spatial structural parameters(SSSPs)to investigate how different MMDs affect forest spatial structure analysis in two pine-oak mixed forests(30 and 57 years old)in southwest China and one old-growth oak forest(>120years old)from northwest China.Our results showed that 1)MMD was closely related to the distribution patterns of forest trees.Tree distribution patterns at each observational scale(r=0-20 m)tended tobecome random as the MMD increased.The older the community,the earlier this random distribution pattern appeared.2)As the MMD increased,neighboring trees became more regularly distributed around a reference tree.In most cases,however,nearest neighbors of a reference tree were randomly distributed.3)Tree species mingling decreased with increasing diameter,but it decreased slowly in older forests.4)No correlations can be found between individual tree size differentiation and MMD.We recommend that comparisons of spatial structures between communities would be more effective if using a unified MMD criterion. 展开更多
关键词 Distribution patterns Minimum MEASURED DIAMETER Mixed FOREST Nearest NEIGHBOR analysis Species MINGLING Uniform angle index
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Automated Identification of Basic Control Charts Patterns Using Neural Networks 被引量:5
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作者 Ahmed Shaban Mohammed Shalaby +1 位作者 Ehab Abdelhafiez Ashraf S. Youssef 《Journal of Software Engineering and Applications》 2010年第3期208-220,共13页
The identification of control chart patterns is very important in statistical process control. Control chart patterns are categorized as natural and unnatural. The presence of unnatural patterns means that a process i... The identification of control chart patterns is very important in statistical process control. Control chart patterns are categorized as natural and unnatural. The presence of unnatural patterns means that a process is out of statistical control and there are assignable causes for process variation that should be investigated. This paper proposes an artificial neural network algorithm to identify the three basic control chart patterns;natural, shift, and trend. This identification is in addition to the traditional statistical detection of runs in data, since runs are one of the out of control situations. It is assumed that a process starts as a natural pattern and then may undergo only one out of control pattern at a time. The performance of the proposed algorithm was evaluated by measuring the probability of success in identifying the three basic patterns accurately, and comparing these results with previous research work. The comparison showed that the proposed algorithm realized better identification than others. 展开更多
关键词 Artificial Neural Networks (ANN) CONTROL Charts CONTROL Charts patternS Statistical Process CONTROL (SPC) Natural pattern SHIFT pattern TREND pattern
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Physical Growth Pattern of Settlements in a Traditional Region, Southwest Nigeria
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作者 Adewale Mukhtar Olayiwola Olayinka Akinsumbo Ajala Johnson Adewale Sangodipe 《International Journal of Geosciences》 2014年第11期1345-1360,共16页
The study examined the growth pattern of settlements in Oke-Ogun area of Oyo State, Nigeria between 1984 and 2011;and predicted the future growth pattern of settlements in the study area. Both primary and secondary da... The study examined the growth pattern of settlements in Oke-Ogun area of Oyo State, Nigeria between 1984 and 2011;and predicted the future growth pattern of settlements in the study area. Both primary and secondary data were used for this study. Primary sources of data include Global Positioning System (GPS), Landsat TM and ETM+ imageries of 1984, 1990, 2000, and 2011. Secondary data included administrative map and population data of the study area. Descriptive statistics and geospatial technique were used to analyse the data collected. The results showed a random pattern of settlement distribution in the study area. Results revealed that settlements covered about 0.52% of the total land area in 1984;1.32% in 2000;and 3.78% in 2011. Whereas linear pattern of growth characterised the periods between 1984 and 1990;clustering, infilling, and fringes were the patterns of growth that characterised the periods between 1990 and 2011. The study predicted that, at an average 1.2% of annual growth rate, settlements will occupy about 44.37% of the total land area by 2031. The study concluded that settlements in the study area varied in the patterns of distribution;the area was dominated by indigenous settlements type with overconcentration of social and economic infrastructures in few centres. 展开更多
关键词 SETTLEMENTS Distribution patterns Oke-Ogun Land Use Infrastructural Facilities SPATIAL DISPARITY Growth pattern LANDSCAPE Transition SPATIAL Metrics
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Surface warming patterns dominate the uncertainty in global water vapor plus lapse rate feedback 被引量:1
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作者 Jingchun Zhang Jian Ma +2 位作者 Jing Che Zhenqiang Zhou Guoping Gao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第3期81-89,共9页
Climate feedbacks have been usually estimated using changes in radiative effects associated with increased global-mean surface temperature. Feedback uncertainties, however, are not only functions of global-mean surfac... Climate feedbacks have been usually estimated using changes in radiative effects associated with increased global-mean surface temperature. Feedback uncertainties, however, are not only functions of global-mean surface temperature increase. In projections by global climate models, it has been demonstrated that the geographical variation of sea surface temperature change brings significant uncertainties into atmospheric circulation and precipitation responses at regional scales. Here we show that the spatial pattern of surface warming is a major contributor to uncertainty in the combined water vapour-lapse rate feedback. This is demonstrated by computing the global-mean radiative effects of changes in air temperature and relative humidity simulated by 31 climate models using a methodology based on radiative kernels. Our results highlight the important contribution of regional climate change to the uncertainty in climate feedbacks, and identify the regions of the world where constraining surface warming patterns would be most effective for higher skill of climate projections. 展开更多
关键词 surface WARMING patternS UNCERTAINTY water vapor FEEDBACK LAPSE RATE FEEDBACK relative humidity air temperature radiative kernels
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Clustering-Inverse: A Generalized Model for Pattern-Based Time Series Segmentation
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作者 Zhaohong Deng Fu-Lai Chung Shitong Wang 《Journal of Intelligent Learning Systems and Applications》 2011年第1期26-36,共11页
Patterned-based time series segmentation (PTSS) is an important task for many time series data mining applications. In this paper, according to the characteristics of PTSS, a generalized model is proposed for PTSS. Fi... Patterned-based time series segmentation (PTSS) is an important task for many time series data mining applications. In this paper, according to the characteristics of PTSS, a generalized model is proposed for PTSS. First, a new inter-pretation for PTSS is given by comparing this problem with the prototype-based clustering (PC). Then, a novel model, called clustering-inverse model (CI-model), is presented. Finally, two algorithms are presented to implement this model. Our experimental results on artificial and real-world time series demonstrate that the proposed algorithms are quite effective. 展开更多
关键词 pattern-Based TIME Series Segmentation Clustering-Inverse Dynamic TIME WARPING Perceptually Important POINTS Evolution Computation Particle SWARM Optimization Genetic Algorithm
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Study on Relation Between Dynamic Pattern of Regional Vertical Strain Rate and Several Strong Earthquakes such as Lijiang(M_s7.0)and Menyuan(M_s6.4)Earthquakes
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作者 Wang Shuangxu Jiang Zaisen +1 位作者 Zhang Xi Chen Bing 《Earthquake Research in China》 2000年第3期30-41,共12页
Making use of the method of obtaining regional vertical strain rate from regional preciseleveling data and gaining dynamic pattern combining with deformation data on spanningfaults, the regional vertical strain dynami... Making use of the method of obtaining regional vertical strain rate from regional preciseleveling data and gaining dynamic pattern combining with deformation data on spanningfaults, the regional vertical strain dynamic evolution characteristics of several moderatelystrong earthquakes such as Lijiang (M_s 7.0) and Menyuan (M_s 6.4) earthquakes occurredin crustal deformation monitoring areas located in the western Yunnan and Qilianshan-Hexiregion. Based on the above-mentioned facts, by studying the time-space nonhomogeneity andstrain energy accumulation status, some criteria for judging the medium. and short-termstrong seismic risk regions according to the regional vertical strain rate dynamic informationare proposed. 展开更多
关键词 Regional VERTICAL strain rate DYNAMIC pattern evolution characteristics Medium- and short-term prediction criterion of strong EARTHQUAKES
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The Airport Economy Development of ZAEZ's Innovation on the Regional Development Pattern 被引量:1
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作者 Zhang Zhancang Chen Ping Peng Junjie 《Contemporary Social Sciences》 2016年第1期80-95,共16页
Regional economic development can be enhanced through the development of an airport economy that includes: changing the regional elements endowment at the micro scale, coupling with regional industries at the medium s... Regional economic development can be enhanced through the development of an airport economy that includes: changing the regional elements endowment at the micro scale, coupling with regional industries at the medium scale, and accelerating tax revenues and employment growth at the macro scale. As a representative example of the Chinese airport economy, the Zhengzhou Airport Economic Zone(ZAEZ) has played a significant leading and demonstrating role in the following fields: deepening the system reforms in an all-round way, promoting the "synchronization of five modernizations", building "one carrier and four systems", constructing "Four Henan", advancing the structural reform of supply-side and integrating the resources of the Henan airport. This article concludes: The supply-side structural reform needs to be accelerated and integrated into the international frontiers under "the Belt and Road" initiative. The ZAEA development has promoted the innovation of regional development patterns and showed the tendency toward the "five modernizations" of future regional development. The airport economy has developed rapidly based on the international aviation transportation system, and may change the traditional development patterns of regional centers located in coastal areas, and open a new era of regional development in the inland regions. 展开更多
关键词 AIRPORT ECONOMY the structural REFORM of supply-side Zhengzhou AIRPORT ECONOMIC Zone regional DEVELOPMENT pattern INLAND era
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