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Derivation of Simplified Models of Plan View Pattern Control Function for Plate Mill 被引量:7
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作者 JIAO Zhi-jie HU Xian-lei ZHAO Zhong LIU Xiang-hua WANG Guo-dong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2007年第4期20-23,共4页
The plan view pattern control theoretical models were simplified. Under the condition of constant volume for the plan view pattern compensation, the relation between the thickness and the length can be simplified to t... The plan view pattern control theoretical models were simplified. Under the condition of constant volume for the plan view pattern compensation, the relation between the thickness and the length can be simplified to the linearity in the segment for the plan view pattern control function. The compensation volume can be dispersed for easy calculation. By comparing the model calculation result with the actual result, it was concluded that the simplified model can be used for the online control process. 展开更多
关键词 plan view pattern control theoretical model simplified model
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Width Compensation and Correction for the Plan View Pattern Control Function on Plate Mill 被引量:5
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作者 Zhi-Jie Jiao Chun-Yu He +1 位作者 Zhong Zhao Jing-Guo Ding 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第5期31-35,共5页
Research works on width compensation and correction were carried out in order to eliminate the effects of the PVPC ( plan view pattern control) on width accuracy of plate mill. The thickness correction calculation f... Research works on width compensation and correction were carried out in order to eliminate the effects of the PVPC ( plan view pattern control) on width accuracy of plate mill. The thickness correction calculation formula was derived for compensation the width deviation caused by PVPC function, and the formula is unified under the thinning and thickening conditions. In order to improve the width calculation accuracy, width spread calculation process was modified with dividing one large reduction pass to several small reduction calculation steps. The thickness wedge was simplified to rectangle based on the volume constant principle, and the width spread model for PVPC was constructed. The width compensation and correction for the PVPC functions are used for the online control process, and the Product dimension accuracy is improved. With the decrease of Crop losses, the Droduct yield was increased with 0. 2%. 展开更多
关键词 Lplate mill plan view pattern control width correction and compensation width spread model
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Calculation of Taper Rolling Time in Plan View Pattern Control Process 被引量:3
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作者 JIAO Zhi-jie HU Xian-lei ZHAO Zhong LIU Xiang-hua WANG Guo-dong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2006年第5期1-3,共3页
The forward slip model with adhesion was used to derive the formula of calculating taper rolling time. The relation between the rolling time and the taper length and the relation between the rolling time and the taper... The forward slip model with adhesion was used to derive the formula of calculating taper rolling time. The relation between the rolling time and the taper length and the relation between the rolling time and the taper thickness can be obtained. The numerical solution for this formula was used on site. According to the simulation result, the roll gap value should be changed linearly with rolling time. 展开更多
关键词 plan view pattern control forward slip model TAPER time calculation
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Control pattern of vocal center for vocalization in ruddy bunting(Emberiza rutila) 被引量:1
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作者 赵静 蒋锦昌 李东风 《Science China(Life Sciences)》 SCIE CAS 2003年第6期615-622,共8页
High vocal center (HVC) can produce single sound with one or two syllables by the sin-gle-type vocal control pattern in songbirds ruddy bunting (Emberiza rutila). It obviously shows left-side dominance in controlling ... High vocal center (HVC) can produce single sound with one or two syllables by the sin-gle-type vocal control pattern in songbirds ruddy bunting (Emberiza rutila). It obviously shows left-side dominance in controlling double syllables, principal frequency (PF) and increasing sound intensity of the evoked calls. Meanwhile, the complex-type control pattern can produce complex calls with multisyllable, and also shows significant left-side dominance in controlling the number of syllables, tone changing and sound intensity. These indicate that left-side HVC controls higher frequency and complicated sentence structure. The basic vocal center, dorsomedial nucleus of the intercollicular complex (DM), controls the monosyllable sound in songbirds, and shows left-side dominance in controlling both the number of syllable and sound intensity. These results not only provide some direct evidence for left-side dominance in high vocal center, but also indicate that there is some internal connection between the high and basic vocal centers in songbirds. 展开更多
关键词 ruddy bunting high VOCAL center basic VOCAL center control pattern left-side dominance.
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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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Control strategy of central pattern generator gait movement under condition of attention selection 被引量:2
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作者 Wei WANG Rubin WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第7期957-966,共10页
As a typical rhythmic movement, human being's rhythmic gait movement can be generated by a central pattern generator (CPG) located in a spinal cord by self- oscillation. Some kinds of gait movements are caused by g... As a typical rhythmic movement, human being's rhythmic gait movement can be generated by a central pattern generator (CPG) located in a spinal cord by self- oscillation. Some kinds of gait movements are caused by gait frequency and amplitude variances. As an important property of human being's motion vision, the attention selection mechanism plays a vital part in the regulation of gait movement. In this paper, the CPG model is amended under the condition of attention selection on the theoretical basis of Matsuoka neural oscillators. Regulation of attention selection signal for the CPG model parameters and structure is studied, which consequentially causes the frequency and amplitude changes of gait movement output. Further, the control strategy of the CPG model gait movement under the condition of attention selection is discussed, showing that the attention selection model can regulate the output model of CPG gait movement in three different ways. The realization of regulation on the gait movement frequency and amplitude shows a variety of regulation on the CPG gait movement made by attention selection and enriches the controllability of CPG gait movement, which demonstrates potential influence in engineering applications. 展开更多
关键词 gait movement attention selection central pattern generator (CPG) movement control strategy
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An Intelligent Single Adaptive Neuron Controller Based on Pattern Recognition
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作者 李巍 李士勇 +1 位作者 郎力 赵长安 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第4期31-33,共3页
The trajectory of the controlled system in phase space has been investigated, and different learning methods are applied to the single adaptive neuron controller according to the pattem of the control system. The adva... The trajectory of the controlled system in phase space has been investigated, and different learning methods are applied to the single adaptive neuron controller according to the pattem of the control system. The advantage of the controller presented has been shown by simulation of a satellite attitude stability control system. 展开更多
关键词 SINGLE adaptive NEURON controlLER INTELLIGENT control pattern recognition phase space
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Nutrient patterns and risk of cataract:a case-control study 被引量:1
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作者 Fatemeh Sedaghat Matin Ghanavati +3 位作者 Parisa Nezhad Hajian Sara Hajishirazi Mehdi Ehteshami Bahram Rashidkhani 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第4期586-592,共7页
AIM:To assess the relation between nutrient patterns and cataract risk.METHODS:This is a hospital-based case-control study with 97 cataract patients and 198 matched controls.Dietary consumption was collected through... AIM:To assess the relation between nutrient patterns and cataract risk.METHODS:This is a hospital-based case-control study with 97 cataract patients and 198 matched controls.Dietary consumption was collected through a valid food frequency questionnaire(FFQ).Nutrient patterns were detected by applying factor analysis.Unconditional logistic regression models were used to estimate odds ratio(ORs) and 95%CIs.RESULTS:We extracted 5 main nutrient patterns.Factor 1 included niacin,thiamin,carbohydrates,protein,zinc,vitamin B6 and sodium(sodium pattern).Factor 2 was characterized by oleic acid,monounsaturated fats,polyunsaturated fats,linoleic acid,trans fatty acid,linolenic acid,vitamin E and saturated fats(fatty acid pattern).The third factor represented high intake of vitamin B12,vitamin D,cholesterol and calcium(mixed pattern).The 4^(th) pattern was high in intake of beta and alpha carotene,vitamin A and vitamin C(antioxidant pattern).Finally,the 5^(th) pattern loaded heavily on docosahexaenoic acid(DHA) and eicosapentaenoic acid(EPA)(omega-3 pattern).In crude and multivariate analysis,the sodium pattern was associated with increased risk of cataract(OR=1.97,95%CI:1.09-3.96).The fatty acid pattern elevated the risk of cataract(OR=1.94,95%CI:1.1-3.86).Antioxidant pattern was associated with a significant 79% reduced risk(2^(nd) category compared with the 1st).Omega-3 pattern was significantly negatively associated with risk of cataract(P=0.04).CONCLUSION:These findings imply that nutrient patterns reflecting a combined consumption of nutrients might be important in the etiology of cataract.Additional studies with more efficient designs are warranted to confirm our findings. 展开更多
关键词 nutrient patterns CATARACT case-control study
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Distribution Patterns of Remaining Hydrocarbons Controlled by Reservoir Architecture of Distributary Channel with Different Channel Style: S2 Formation of Songliao Basin, China
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作者 LI Weiqiang YIN Taiju +1 位作者 ZHAO Lun ZHAO Liangdong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期129-130,共2页
1 Introduction Reservoir architecture analysis of distributary channel of Daqing oilfield has drawn consistent interest among development geologists and petroleum engineers over the last decade(Lv et al.,1999;Zhou et ... 1 Introduction Reservoir architecture analysis of distributary channel of Daqing oilfield has drawn consistent interest among development geologists and petroleum engineers over the last decade(Lv et al.,1999;Zhou et al.,2008;Zhang et 展开更多
关键词 China Distribution patterns of Remaining Hydrocarbons controlled by Reservoir Architecture of Distributary Channel with Different Channel Style
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“十四五”期间我国水稻病虫害发生规律演变与绿色防控技术集成创新 被引量:1
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作者 卓富彦 张熠玚 +2 位作者 郭永旺 刘慧 鄂文弟 《中国稻米》 北大核心 2025年第4期9-12,共4页
水稻作为我国主要的口粮作物,其病虫害防治工作关乎国家粮食安全。本文在对2016年至2024年全国植保专业统计资料分析的基础上,全面总结回顾了“十四五”期间水稻病虫害的发生特征、造成的危害损失以及防控工作取得的成效。同时,系统梳... 水稻作为我国主要的口粮作物,其病虫害防治工作关乎国家粮食安全。本文在对2016年至2024年全国植保专业统计资料分析的基础上,全面总结回顾了“十四五”期间水稻病虫害的发生特征、造成的危害损失以及防控工作取得的成效。同时,系统梳理了农业防治、生物防治、化学防治等绿色防控技术的最新研究进展以及模式创新成果。在此基础上,针对未来水稻绿色安全生产提出了具有针对性的建议,以期为水稻等粮油作物大面积单产提升提供切实可行的实践参考。 展开更多
关键词 水稻 病虫害 发生规律 绿色防控 集成创新
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基于无参数聚类和改进支持向量机多特征融合的控制图模式识别 被引量:1
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作者 潘柏松 邱敏鹏 钱丽娟 《计算机集成制造系统》 北大核心 2025年第3期855-868,共14页
为提升智能制造中产品质量管控的准确性和及时性,提出一种基于无参数聚类和改进支持向量机多特征融合的控制图模式识别方法。采用蒙特卡洛法生成模拟数据集,考虑了质量特征均值微动的情况。将无参数聚类提取的历史数据信息特征,与统计... 为提升智能制造中产品质量管控的准确性和及时性,提出一种基于无参数聚类和改进支持向量机多特征融合的控制图模式识别方法。采用蒙特卡洛法生成模拟数据集,考虑了质量特征均值微动的情况。将无参数聚类提取的历史数据信息特征,与统计特征以及形状特征进行融合,通过交叉实验获取最优特征组合。借助白鲸算法改进支持向量机分类器,实现对控制图异常模式的准确高效识别。通过仿真实验比较了不同分类器在不同数据集复杂程度下的识别准确性和效率,结果显示,所提出的分类模型对数据集复杂程度的影响较小,即使在复杂数据集上也能保持98.63%以上的识别精度,并具备训练速度快、计算复杂度低的优点。 展开更多
关键词 控制图 模式识别 特征融合 无参数聚类
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鄂尔多斯盆地深部8号煤储层孔隙发育模式及其控气作用
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作者 黄道军 许浩 +6 位作者 虎建玲 董煜 焦鹏帅 陈世达 周国晓 吴小卓 武衡 《煤炭科学技术》 北大核心 2025年第3期115-123,共9页
鄂尔多斯盆地内部深部8号煤分布广泛,煤阶跨度大,是勘探的主要目的层。然而,目前对于盆地内部深部煤储层的孔隙发育规律及其控制因素缺乏系统、全面的理解,尤其是在深部煤储层孔隙发育模式及其控气作用方面尚未进行深入研究。基于盆地... 鄂尔多斯盆地内部深部8号煤分布广泛,煤阶跨度大,是勘探的主要目的层。然而,目前对于盆地内部深部煤储层的孔隙发育规律及其控制因素缺乏系统、全面的理解,尤其是在深部煤储层孔隙发育模式及其控气作用方面尚未进行深入研究。基于盆地内14口探井岩心测试分析数据,系统分析了煤储层的孔隙发育特征和发育模式,并探讨了其分布规律和控气作用。结果表明:随着变质程度增加,研究区8号深部煤储层微孔和介孔的孔体积均明显增高,宏孔体积逐渐降低。其中,微孔主要为气孔,尤以孔径为0.4~0.9 nm孔隙最为发育,介孔相对不发育。宏孔由中−低变质程度煤发育的胞腔孔和屑间孔转变为中−高变质程度煤发育的内生裂隙。由北到南随着变质程度的增加(R_(o,max)为0.60%~2.86%),盆地内8号深部煤储层孔隙发育模式可分为:宏孔发育型、双峰发育型和微孔发育型,其中,宏孔发育型煤储层含气量较低,但也含有一定比例的游离气;双峰发育型是盆地内8号深部煤储层的主要孔隙发育模式,该类型储层微孔、宏孔均较为发育,最有利于吸附气和游离气的富集与产出;微孔发育型煤储层吸附能力最强,含气性最优,资源潜力大,但渗透性较差,需采用极限压裂方式提升储层的渗透能力。 展开更多
关键词 鄂尔多斯盆地 8号煤 变质程度 孔隙发育模式 控气作用
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浪漫与现实的交融——楚都纪南城规划策略探讨
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作者 王发堂 沈旺洁 《建筑史学刊》 2025年第3期109-119,共11页
通过对纪南城已勘探的城垣城门数据进行尺度换算与分析,在探究其规划特点的过程中,发现存在两道方格网模数控制城垣与城门的现象。结合分析纪南城的整体形态规划过程,认为纪南城的空间格局折中了楚国哲学思想的浪漫性与传统周礼的现实... 通过对纪南城已勘探的城垣城门数据进行尺度换算与分析,在探究其规划特点的过程中,发现存在两道方格网模数控制城垣与城门的现象。结合分析纪南城的整体形态规划过程,认为纪南城的空间格局折中了楚国哲学思想的浪漫性与传统周礼的现实规范性,是战国时期都城建设的又一次创新发展。为研究纪南城的规划手法提供了理论依据,也有助于深入理解战国时期的都城建设历史。 展开更多
关键词 楚国 纪南城 模数控制 城市格局
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青藏高原地区黄河反Z形河道的成因机制分析
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作者 李永军 王芊 +3 位作者 段丰浩 彭建兵 王盼龙 程三友 《人民黄河》 北大核心 2025年第1期59-66,共8页
河流演化取决于区域地球动力学过程。青藏高原东北缘黄河反Z形河段流经五大构造带,大多数河段产于断层破碎带和碎裂岩带中,河道大多分布于造山带山前大断裂、构造单元结合部。NWW向断裂主控长线型延伸河道,NE向、NW向断裂主控短折线拐... 河流演化取决于区域地球动力学过程。青藏高原东北缘黄河反Z形河段流经五大构造带,大多数河段产于断层破碎带和碎裂岩带中,河道大多分布于造山带山前大断裂、构造单元结合部。NWW向断裂主控长线型延伸河道,NE向、NW向断裂主控短折线拐弯河道,NE向、NW向两组断裂交切形成锯齿状摆动延伸河道。青藏高原持续向NE方向挤压过程中,在阿拉善和鄂尔多斯两地块的正向联合阻挡下,构造上表现为NWW-SEE向复合与叠加造山带,地貌上表现为隆起与凹陷相间,河流主流向总体与主构造带展布方向平行。受到扬子、秦岭、鄂尔多斯等块体阻挡后,加剧了NE向张性走滑断裂活动,导致河流由原SEE向短折线大角度向NE向拐弯,并驱使NE向张性走滑断裂的NW盘大幅度沉降,形成西高东低的斜倾式地堑,河流向NE向前行,在遭遇下一个NWW-SEE向断裂带阻挡后,逼迫河流NW-NWW向回流,形成了黄河独有的斜U形大回流。断裂构造是控制河道形成、演化、延伸、拐弯和构成反Z形河道组合样式的主控因素。 展开更多
关键词 黄河 反Z形河道 断裂控河 青藏高原
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Safer Design and Less Cost Operation for Low-Traffic Long-Road Illumination Using Control System Based on Pattern Recognition Technique 被引量:1
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作者 Muhammad M. A. S. Mahmoud Leyla Muradkhanli 《Intelligent Control and Automation》 2020年第3期47-62,共16页
The paper covers analysis and investigation of lighting automation system in low-traffic long-roads. The main objective is to provide optimal solution between expensive safe design that utilizes continuous street ligh... The paper covers analysis and investigation of lighting automation system in low-traffic long-roads. The main objective is to provide optimal solution between expensive safe design that utilizes continuous street lighting system at night for the entire road, or inexpensive design that sacrifices the safety, relying on using vehicles lighting, to eliminate the problem of high cost energy consumption during the night operation of the road. By taking into account both of these factors, smart lighting automation system is proposed using Pattern Recognition Technique applied on vehicle number-plates. In this proposal, the road is sectionalized into zones, and based on smart Pattern Recognition Technique, the control system of the road lighting illuminates only the zone that the vehicles pass through. Economic analysis is provided in this paper to support the value of using this design of lighting control system. 展开更多
关键词 Road Lighting control Road Lighting Automation Vehicle Number-Plate pattern Recognition Smart Grid Power Management Low Traffic Roads Image Processing
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新发突发重大传染病:发生演变规律、国际防控政策举措与启示
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作者 江晓波 沈东婧 +2 位作者 李莎 姚远 王小理 《生命科学》 2025年第4期459-465,共7页
本文总结21世纪以来新发突发重大传染病的发生演变规律及其内在的驱动因素,梳理新冠疫情后国际社会针对重大传染病所采取的战略规划和政策举措,并对未来我国的重大传染病防控工作提出政策建议。
关键词 重大传染病 演变规律 防控政策
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起伏地形中躯干关节四足机器人地形自适应控制策略
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作者 艾青林 付博 +1 位作者 宋国正 刘元宵 《高技术通讯》 北大核心 2025年第9期969-978,共10页
针对四足机器人在起伏不平地形中运动稳定性差的问题,提出了一种基于多传感器信息感知的起伏地形运动自适应控制策略。采用机器人机身多传感器感知足端触地信息,通过机器人运动学模型和机身多传感器信息完成机器人足端运动位置解算,融... 针对四足机器人在起伏不平地形中运动稳定性差的问题,提出了一种基于多传感器信息感知的起伏地形运动自适应控制策略。采用机器人机身多传感器感知足端触地信息,通过机器人运动学模型和机身多传感器信息完成机器人足端运动位置解算,融合足端触地信息与足端位置信息对机器人当前运动地形进行分类。在此基础上,通过构建躯干关节四足机器人多层中枢模式发生器(central pattern generator,CPG)控制网络实现机器人机身姿态与足端运动轨迹控制以适应当前地形。仿真和实验表明,本文控制方法可以提高机器人在起伏地形中的运动稳定性。 展开更多
关键词 四足机器人 地形感知 中枢模式发生器 自适应控制
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金沙江奔子栏-真达乡河段滑坡分布规律及其控制因素研究 被引量:1
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作者 廖俊生 许强 +4 位作者 张富灵 巨袁臻 杨建 郭德存 何万通 《工程地质学报》 北大核心 2025年第1期201-212,共12页
金沙江奔子栏-真达乡河段位于青藏高原东南缘与横断山脉交界的位置,地质活动强烈,滑坡灾害频发。为进一步掌握金沙江奔子栏至真达乡河段水电站库区及其所属范围的滑坡分布规律及其控制因素,以区内调查和遥感识别的189处滑坡为基础,研究... 金沙江奔子栏-真达乡河段位于青藏高原东南缘与横断山脉交界的位置,地质活动强烈,滑坡灾害频发。为进一步掌握金沙江奔子栏至真达乡河段水电站库区及其所属范围的滑坡分布规律及其控制因素,以区内调查和遥感识别的189处滑坡为基础,研究河段滑坡分布的规律,提出相关的控制因素并分析其对滑坡分布规律的影响,通过相关性分析确定主要的控制因素。结果表明:①区内滑坡分布规律的控制因素主要是坡体结构,其次是工程地质岩组和地形地貌;②逆向坡的分布对滑坡发育存在显著影响,逆向坡是区内滑坡的主要坡体结构,为岩体的变形破坏过程提供了缓慢变形的结构基础,使得风化碎裂的岩体堆积在原位构成滑体;③工程地质岩组的分布导致滑坡空间分布规律呈明显的差异性特征,较软岩组中滑坡发育数量最多,占比50.8%;④滑坡主要发育于陡-极陡的中小起伏中山地貌中,地形坡度多介于15°~41°之间,以25°~33°为主,倾向以东西向为主;⑤断裂构造和河流形态控制着局部的滑坡分布,断层距与发育滑坡数量之间存在明显的负相关性。研究成果对区域性的滑坡灾害防治工作和经济稳定发展具有重要意义。 展开更多
关键词 金沙江上游 滑坡 分布规律 控制因素
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国土空间规划背景下黄河流域水生态空间格局演变特征及其影响因素 被引量:2
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作者 薄立明 赵浪 +2 位作者 尹力 张翔 魏伟 《水土保持研究》 北大核心 2025年第2期178-190,共13页
[目的]科学认知黄河流域上、中、下游水生态空间格局演化特征及影响因素,促进水资源用途管制客体向国土空间规划体系治理系统的融入,推动黄河流域生态保护和高质量发展。[方法]采用空间转移矩阵、最优地理探测器等量化模型分析黄河流域... [目的]科学认知黄河流域上、中、下游水生态空间格局演化特征及影响因素,促进水资源用途管制客体向国土空间规划体系治理系统的融入,推动黄河流域生态保护和高质量发展。[方法]采用空间转移矩阵、最优地理探测器等量化模型分析黄河流域上、中、下游水生态空间格局演变的区域差异,剖析了水生态空间格局演变路径并揭示其内在影响因素。[结果](1)黄河流域水生态空间规模为2.76万km^(2),仅占流域国土总面积的2.28%,上、中、下游水生态空间规模占比为22∶2∶3,研究期内规模性扩张了4 989.90 km^(2),上游地区增长规模最大,下游地区增长幅度最剧烈。(2)上游地区水生态空间主要与其他生态空间发生交叉转换,引起水生态空间大规模扩张,其次是与农业空间交互转换造成水生态空间小规模流失;中游地区水生态空间主要与农业空间发生交叉转换,其次是其他生态空间,引起水生态空间小规模扩张;下游地区农业空间向水生态空间的转换引起水生态空间大规模扩张的同时水生态空间也规模性转换为城镇空间。(3)上游地区水生态空间规模性扩张核心影响因素是水资源“液态化”的水文循环过程,流失则是主要由第一、三产业发展诉求驱动;中游地区水生态空间格局演变整体表现为政府财政所主导的适配地区自然地理条件、社会经济发展的水资源调配过程;下游地区则是水生态空间伴随城镇化进程在农业地区和城镇地区的转移。[结论]黄河流域上、中、下游水生态空间格局演变特征、路径和影响因素差异显著,需要根据各区域水资源保护利用的发展定位,建立起共同治理、协同发展的流域协作体系。 展开更多
关键词 水生态空间 国土空间规划 用途管制 时空格局 黄河流域
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某“日”型UTLT主隧道送风风速对火灾烟气控制的影响
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作者 李凯玲 林雪 +3 位作者 魏刘阳 屈璐 姚田田 傅文静 《西安科技大学学报》 北大核心 2025年第2期317-327,共11页
为解决异型城市地下交通联系隧道(简称“UTLT”)通风排烟设计难题,探索适用于不同横向通风下的最佳送风风速。基于Pyrosim软件探索主隧道在1.54,3.54,5.54,7.54,9.54,11.54 m/s送风速度时烟气蔓延的规律,以西安市某“日”型隧道为例展... 为解决异型城市地下交通联系隧道(简称“UTLT”)通风排烟设计难题,探索适用于不同横向通风下的最佳送风风速。基于Pyrosim软件探索主隧道在1.54,3.54,5.54,7.54,9.54,11.54 m/s送风速度时烟气蔓延的规律,以西安市某“日”型隧道为例展开模拟分析,研究不同工况中的通风效果。结果表明:主隧道在采用半横向通风时,各送风速度下火源下游区域各项火灾参数均满足烟控指标要求,火源上游仅在送风速度为1.54 m/s时,各项参数满足要求,因此送风速度宜在1.54 m/s附近取值,设置疏散路径应着重考虑火源下游区域;在采用全横向通风时,送风速度为5.54 m/s时各项指标值更优,可将5.54 m/s作为最佳送风速度;由于全横向通风排烟方式各项火灾参数在隧道局部区域波动较大,不易控制,且考虑到工程量以及经费需求,因此更建议采用半横向通风排烟。研究结果可以为“日”型UTLT的通风系统组织与设计提供一定的理论参考。 展开更多
关键词 “日”型UTLT 火灾烟气 通风方式 送风速度 烟气蔓延规律 烟控措施
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