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Machine Learning for Hybrid Line Stability Ranking Index in Polynomial Load Modeling under Contingency Conditions
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作者 P.Venkatesh N.Visali 《Intelligent Automation & Soft Computing》 SCIE 2023年第7期1001-1012,共12页
In the conventional technique,in the evaluation of the severity index,clustering and loading suffer from more iteration leading to more com-putational delay.Hence this research article identifies,a novel progression f... In the conventional technique,in the evaluation of the severity index,clustering and loading suffer from more iteration leading to more com-putational delay.Hence this research article identifies,a novel progression for fast predicting the severity of the line and clustering by incorporating machine learning aspects.The polynomial load modelling or ZIP(constant impedances(Z),Constant Current(I)and Constant active power(P))is developed in the IEEE-14 and Indian 118 bus systems considered for analysis of power system security.The process of finding the severity of the line using a Hybrid Line Stability Ranking Index(HLSRI)is used for assisting the concepts of machine learning with J48 algorithm,infers the superior affected lines by adopting the IEEE standards in concern to be compensated in maintaining the power system stability.The simulation is performed in the WEKA environment and deals with the supervisor learning in order based on severity to ensure the safety of power system.The Unified Power Flow Controller(UPFC),facts devices for the purpose of compensating the losses by maintaining the voltage characteristics.The finite element analysis findings are compared with the existing procedures and numerical equations for authentications. 展开更多
关键词 CONTINGENCY hybrid line stability ranking index(HLSRI) machine learning(ML) unified power flow controller(UPFC) ZIP load modelling
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Glycemic index,glycemic load and insulinemic index of Chinese starchy foods 被引量:12
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作者 Meng-Hsueh Amanda Lin Shin Lu Jenshinn Lin 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第39期4973-4979,共7页
AIM:To determine the glycemic index(GI),glycemic load(GL)and insulinemic index(Ⅱ)of five starchy foods that are commonly used in Chinese diets.METHODS:Ten healthy subjects aged between 20-30 years were recruited.Each... AIM:To determine the glycemic index(GI),glycemic load(GL)and insulinemic index(Ⅱ)of five starchy foods that are commonly used in Chinese diets.METHODS:Ten healthy subjects aged between 20-30 years were recruited.Each subject was asked to consume 50 g of available carbohydrate portions of test foods and reference food.Finger capillary blood samples were collected at the start of eating and 15,30,45,60,90 and 120 min after consumption.The GI and Ⅱ of foods were calculated from the ratio of incremental area under the glucose/insulin response curves of test and reference foods.The GL for each test food was determined from its GI value and carbohydrate content.RESULTS:The results showed that brown rice elicited the highest postprandial glucose and insulin responses,followed by taro,adlay,yam and mung bean noodles,which produced the lowest.Among the five starchy foods,brown rice evoked the highest GI and GL at 82±0.2 and 18±0.2,followed by taro(69±0.4,12±0.2),adlay(55±0.4,10±0.2),yam(52±0.3,9±0.0)and mung bean noodles(28±0.5,7±0.2),respectively.The Ⅱ values of the test foods corresponded with GI values.Similarly,brown rice gave the highest Ⅱ at 81±0.1,followed by taro(73±0.3),adlay(67±0.3),yam(64±0.5) and mung bean noodles(38±0.3).All five starchy foods had lower GI,GL and Ⅱ than reference bread(P<0.05).CONCLUSION:The GI,GL and Ⅱ values of starchy foods provide important information for the public to manage their diet and could be useful for the prevention of lifestyle-related diseases such as diabetes mellitus. 展开更多
关键词 Glycemic RESPONSE Glycemic index Glycemic load Insulinemic RESPONSE Insulinemic index
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Glycemic index and glycemic load of selected Chinese traditional foods 被引量:4
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作者 Stephen Heung-sang Wong 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第12期1512-1517,共6页
AIM:To determine the glycemic index(GI)and glycemic load(GL)values of Chinese traditional foods in Hong Kong.METHODS:Fifteen healthy subjects(8 males and 7 females)volunteered to consume either glucose or one of 23 te... AIM:To determine the glycemic index(GI)and glycemic load(GL)values of Chinese traditional foods in Hong Kong.METHODS:Fifteen healthy subjects(8 males and 7 females)volunteered to consume either glucose or one of 23 test foods after 10-14 h overnight fast.The blood glucose concentrations were analyzed immediately before,15,30,45,60,90 and 120 min after food consumption using capillary blood samples.The GI value of each test food was calculated by expressing the incremental area under the blood glucose response curve(IAUC)value for the test food as a percentage of each subject's average IAUC value for the glucose.The GL value of each test food was calculated as the GI value of the food multiplied by the amount of the available carbohydrate in a usual portion size,divided by 100.RESULTS:Among all the 23 Chinese traditional foods tested,6 of them belonged to low GI foods(Tuna Fish Bun,Egg Tart,Green Bean Dessert,Chinese Herbal Jelly,Fried Rice Vermicelli in Singapore-style,and Spring Roll),10 of them belonged to moderate GI foods(Baked Barbecued Pork Puff,Fried Fritter,"Mai-Lai"Cake,"Pineapple"Bun,Fried Rice Noodles with Sliced Beef,Barbecue Pork Bun,Moon Cakes,Glutinous Rice Ball,Instant Sweet Milky Bun,and Salted Meat Rice Dumpling),the others belonged to high GI foods(Fried Rice in Yangzhou-Style,Sticky Rice Wrapped in Lotus Leaf,Steamed Glutinous Rice Roll,Jam and Peanut Butter Toast,Plain Steamed Vermicelli Roll,Red Bean Dessert,and Frozen Sweet Milky Bun).CONCLUSION:The GI and GL values for these Chinese traditional foods will provide some valuable information to both researchers and public on their food preference. 展开更多
关键词 Glycemic index Glycemic load Chinese traditional foods
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Estimating Unconfined Compressive Strength of Sedimentary Rocks in United Arab Emirates from Point Load Strength Index 被引量:2
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作者 Hussain Salah Maher Omar Abdallah Shanableh 《Journal of Applied Mathematics and Physics》 2014年第6期296-303,共8页
In this paper, three rock types including Sandstone, Mudstone, and Crystalline Gypsum were part of a laboratory study conducted to develop a dataset for predicting the unconfined compressive strength of UAE intact sed... In this paper, three rock types including Sandstone, Mudstone, and Crystalline Gypsum were part of a laboratory study conducted to develop a dataset for predicting the unconfined compressive strength of UAE intact sedimentary rock specimens. Four hundred nineteen rock samples from various areas along the coastal region of the UAE were collected and tested for the development of this dataset and evaluation of models. From the statistical analysis of the data, regression equations were established among rock parameters and correlations were expressed and compared by the ones proposed in literature. 展开更多
关键词 SEDIMENTARY ROCKS UNITED Arab Emirates Unconfined COMPRESSIVE STRENGTH Point load STRENGTH index Regression Analysis
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Glycemic Index, Glycemic Load, and Glycemic Response to Pomelo in Patients with Type 2 Diabetes
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作者 邵诗颖 徐惟捷 +12 位作者 陶静 张建华 周新荣 袁刚 杨雁 张静 张红艳 徐强 邓秀新 胡蜀红 张木勋 刘喆隆 余学锋 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2017年第5期711-718,共8页
Food intake has a great influence on blood glucose in patients with diabetes. This study was to determine the glycemic index(GI) and glycemic load(GL) of a particular pomelo named Majia pomelo and its effects on p... Food intake has a great influence on blood glucose in patients with diabetes. This study was to determine the glycemic index(GI) and glycemic load(GL) of a particular pomelo named Majia pomelo and its effects on postprandial glucose(PPG) in patients with type 2 diabetes(T2D). Twenty healthy subjects and 20 T2D patients(controlled on lifestyle measures and/or metformin) were tested on 2 separate days with 50 g of glucose and 50 g equivalent of carbohydrates from Majia pomelo for GI measurement. To test effects of Majia pomelo on PPG, 19 hospitalized T2D patients(controlled on insulin therapy) were selected for a 9-day study. The dose of insulin for each patient was adjusted on the first 3 days. A total of 100 g Majia pomelo was consumed per meal in the last 3 tested days. Blood glucose was measured to evaluate the glycemic excursions. The GIs for Majia pomelo in healthy individuals and T2D patients were 78.34±1.88 and 72.15±1.95 respectively. The value of GL was as low as 4.23 in diabetic patients with serving size of 100 g pomelo, indicting Majia pomelo as a high GI but low GL fruit. Consumption of Majia pomelo in hospitalized T2D patients did not cause significant glucose fluctuation. It was concluded that high GI pomelo can serve as a low GL fruit if it is consumed with a limited daily amount and thus can be supplied to diabetic patients. These results may mean more varieties of food choices for T2D patients. 展开更多
关键词 glycemic index glycemic load type 2 diabetes POMELO
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Glycemic Index and Glycemic Load of Selected Staples Based on Rice,Yam and Cassava Commonly Consumed in Cote d’Ivoire 被引量:1
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作者 Camille Adam Kouamé Nestor Kouakou Kouassi +4 位作者 Aissatou Coulibaly Denis Yao N’dri Georges Gnomblesson Tiahou Lokrou Adrien Georges N’guessan Amani 《Food and Nutrition Sciences》 2014年第4期308-315,共8页
Integrating information on the glycemic index (GI) and the glycemic load (GL) of diet is limited in C?te d’Ivoire because of the lack of data. Thus, this study was undertaking for the local management and prevention ... Integrating information on the glycemic index (GI) and the glycemic load (GL) of diet is limited in C?te d’Ivoire because of the lack of data. Thus, this study was undertaking for the local management and prevention of diabetes mellitus and its complications based on nutritional data (GI and GL values). The study included ten healthy subjects with 7 males, 3 females (28 ± 2 years on average age and 20.5 ± 1.7 on average BMI). Participants tested three different meals with equal carbohydrate load (50 g). Blood samples were obtained at 0, 15, 30, 45, 60, 90 and 120 min before and after consumption for glucose levels determination. GIs were determined using a standard method with glucose as reference food and data were used for GLs calculating. Data showed that GIs value of pounded yam with eggplant sauce and cassava paste with granulates palm nut sauce were high ranging to 94 to 86 respectively while rice with groundnut sauce, have a low GI (GI = 45). Nevertheless, the GLs of the all the test foods are high with the values of 47, 43 and 23 (g) for pounded yam with eggplant sauce, cassava paste with granulates palm nut sauce and rice with groundnut sauce respectively. According to GIs and GLs data, the three test foods must be consumed moderately in a diet. So, it is important to associate GL data to GI data of Ivorian traditional foods for the management and the prevention of diabetes mellitus in C?te d’Ivoire and in others countries sharing the same food tradition. 展开更多
关键词 Diabetes Mellitus Management Prevention Glycemic index Glycemic load Ivorian Traditional Foods
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Simulating of marble subjected to uni-axial loading using index-parabola damage model
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作者 温世游 李夕兵 骆达成 《中国有色金属学会会刊:英文版》 CSCD 2001年第2期293-296,共4页
The limitations of several existing classical rock damage models were critically appraised. Thereafter, a description of a new model to estimate the response of rock was provided. The results of an investigation lead ... The limitations of several existing classical rock damage models were critically appraised. Thereafter, a description of a new model to estimate the response of rock was provided. The results of an investigation lead to the development and confirmation of a new index parabola damage model. The new model is divided into two parts, fictitious damage and real damage and bordered by the critical damage point. In fictitious damage, the damage variable follows the index distribution, while in the real damage a parabolic distribution is used. Thus, the so called index parabola damage model is derived. The proposed damage model is applied to simulate the damage procedure of marble under uni axial loading. The results of the tests show that the proposed model is in excellent agreement with experimental data, in particular the nonlinear characteristic of rock deformation is adequately represented. [ 展开更多
关键词 index parabola damage model uni axial loading nonlinear behavior of marble
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Utilizing Stability Index Tracing for Precise Load Buses Identification in Load Shedding Problem
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作者 Z. Hamid I. Musirin M. M. Othman 《Engineering(科研)》 2013年第1期168-173,共6页
This paper proposes a new approach for suitable load buses identification via stability index tracing in performing corrective load shedding. The proposed identification technique is called the Fast Voltage Stability ... This paper proposes a new approach for suitable load buses identification via stability index tracing in performing corrective load shedding. The proposed identification technique is called the Fast Voltage Stability Index Load Tracing (FVSI-LT). By implementing a power tracing algorithm, a group of major contributors on the stress experienced by a power system is able to be precisely identified by a system operator (SO) based on the traced values of FVSI. To be precise, the traced FVSI via FVSI-LT can be used to form a ranking list indicating the priority of buses committed for shedding purpose. After designing a Fuzzy Inference System (FIS) for deciding the allowable load powers to be shed and performing experiment on IEEE 57-Bus reliability test system (RTS), it is revealed that the ranking list provided by FVSI-LT results to the most consistent improvement in terms of voltage stability and losses minimization. 展开更多
关键词 fuzzy LOGIC FVSI-LT load SHEDDING stability index TRACING
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Relationship between Vegetation Index and Forest Surface Fuel Load in UAV Multispectral Remote Sensing
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作者 Yufei ZHOU Zhenshi WANG +6 位作者 Yingxia ZHONG Qiang LI Shujing WEI Sisheng LUO Zepeng WU Ruikun DAI Xiaochuan LI 《Asian Agricultural Research》 2022年第10期33-36,41,共5页
[Objectives]To explore the relationship between vegetation index and forest surface fuel load.[Methods]UAV multispectral remote sensing was used to obtain large-scale forest images and obtain structural data of forest... [Objectives]To explore the relationship between vegetation index and forest surface fuel load.[Methods]UAV multispectral remote sensing was used to obtain large-scale forest images and obtain structural data of forest surface fuel load.This experimental area was located in Gaoming District,Foshan City,Guangdong Province.The average surface fuel load of the experimental area was as high as 39.33 t/ha,and the forest surface fuel load of Pinus elliottii was the highest.[Results]The normalized difference vegetation index(NDVI)and enhanced vegetation index(EVI)had a moderately strong correlation with the forest surface fuel load.The regression model of NDVI(X)and forest surface fuel load(Y)was established:Y=-5.9354X+8.4663,and the regression model of EVI(X)and forest surface fuel load(Y)was established:Y=-5.8485X+6.7271.The study also found that the linear relationship between NDVI and surface fuel load was more significant.[Conclusions]Both NDVI and EVI have moderately strong correlations with forest surface fuel load.NDVI is moderately or strongly correlated with the surface fuel load of Pinus massoniana forest,shrub grassland,broad-leaf forest and bamboo forest,while EVI is only strongly correlated with surface fuel load of broad-leaf forest and bamboo forest.It is expected that the relationship between other vegetation indices and forest surface fuel load can be obtained by the method in this study,so as to find a more universal vegetation index for calculating surface fuel load. 展开更多
关键词 Unmanned AERIAL vehicle (UAV) MULTISPECTRAL REMOTE sensing VEGETATION index Fuel load
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Rice and Bean:Glycemic Index and Glycemic Load of the“Baiao de Dois”
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作者 Tatiana Uchoa Passos Helena Alves de Carvalho Sampaio +3 位作者 Soraia Pinheiro Machado Arruda Maria Luisa Pereira de Melo Jose Wellington de Oliveira Lima Daianne Cristina Rocha 《Agricultural Sciences》 2014年第9期770-775,共6页
The “bai?o de dois” is a typical Brazilian dish and a rich combination of rice and beans. This preparation has a high nutritional value but its effect on glycemic response is not yet studied. To determine the glycem... The “bai?o de dois” is a typical Brazilian dish and a rich combination of rice and beans. This preparation has a high nutritional value but its effect on glycemic response is not yet studied. To determine the glycemic index and glycemic load of foods can help prescribing diets and as a result, improving the treatment and prevention of chronic diseases. This study aimed to access the glycemic index (GI) and glycemic load (GL) of “bai?o de dois”. Following the protocol recommended by the Food and Agriculture Organization, 6 volunteers were recruited to perform blood glucose tests. Each volunteer performed three glucose tolerance tests and a test with “bai?o de dois”. All tests were undertaken in separate weeks. Through the calculation of the areas under each of the curves, it was possible to access the GI of “bai?o de dois” by the average values of six GIs found for each volunteer. It was calculated that the GL of each portion tested and recommended servings per capita. It was found that “bai?o de dois” had low GI (44) and GL (6) at the recommended per capita, but high GL (22) at the portion tested (bigger than the recommended). The “bai?o de dois” do not present a potential risk for developing chronic diseases, but it is recommended consumption to be monitored. 展开更多
关键词 Glycemic index Glycemic load Regional Food Baiao de Dois Chronic Disease
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Glycemic Index and Glycemic Load of Juice from Edible Wild Fruits (Adansonia digitata, Tamarindus indica and Parkia biglobosa) Consumed in Cote d’Ivoire
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作者 Antoine Kouame Kouassi Nestor Kouakou Kouassi +3 位作者 Maxwell Avit Grah Beugre Denis Yao N’Dri Georges N’Guessan Amani Dago Gnakri 《Journal of Biosciences and Medicines》 2018年第1期63-74,共12页
The diabetes mellitus is a public health problem in C?te d’Ivoire. The Glycemic index (GI) and the Glycemic load (GL) determination of commonly consumed foods such as juice fruits is an alternative to prevent metabol... The diabetes mellitus is a public health problem in C?te d’Ivoire. The Glycemic index (GI) and the Glycemic load (GL) determination of commonly consumed foods such as juice fruits is an alternative to prevent metabolic diseases. This study carried out three wild fruits locally named Baobab (Adansonia digitata), Tomi (Tamarindus indica) and Néré (Parkia biglobosa) collected at maturity stage. The juices from the pulp of fruits have been elaborated, pasteurized, submitted to microbiological and physicochemical analysis before GIs/GLs determination. Ten healthy subjects with body mass index and age average respectively 21.57 ± 1.06 and 28 ± 2 years old tested the three juices and glucose (50 g) as reference food. Blood samples have been collected at 0, 15, 30, 45, 60, 90 and 120 min after foods consumption. The GIs/GLs has been determined according to ISO/FDI 26642:2010 protocol. Data showed that pasteurized juices has a weak microbiologic load (1.0102 - 2.4102 of Mesophylls Aerobic Germs) and not contain pathogen germs. The GI and GL of Néré juice are high with respective values of 89.54 ± 1.63 and 29.22 ± 4.09 whereas those of Baobab and Tomi juice are moderate with respective GI/GL values of 66.48 ± 2.12/13.24 ± 1.99 and 60.41 ± 2.63/12.87 ± 1.67. The juice of Néré should be consumed occasionally when those of Baobab and Tomi should be consumed with moderation. It would be suitable to know more about the GI and GL of all the juice fruits produced locally so as to prevent efficiently diabetes mellitus in the country. 展开更多
关键词 Edible Wild Fruits Pasteurized Juices Glycemic index Glycemic load Cote D’Ivoire
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Research on cognitive load evaluation with subjective method in manual assembly
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作者 任彬 ZHOU Qinyu +1 位作者 LI Qibing LUO Wenfa 《High Technology Letters》 EI CAS 2023年第4期434-444,共11页
Subjective scales have different kinds of applicability in diverse fields.This study intends to implement a quantitative approach to determine the applicability of subjective scales in manual as-sembly work and evalua... Subjective scales have different kinds of applicability in diverse fields.This study intends to implement a quantitative approach to determine the applicability of subjective scales in manual as-sembly work and evaluate the cognitive load of assembly workers.A multi-scale research paradigm based on subjective evaluation method is proposed.Three typical task stages are extracted from the process of assembly work.The National Aeronautics and Space Administration Task Load Index(NASA-TLX)scale,PAAS scale and Workload Profile Index Ratings(WP)scale are selected for the design of 3×3 multi-factor mixed experiment.The power spectrum density(PSD)characteris-tics of electroencephalogram(EEG)are utilized to identify the difficulty levels of the three task sta-ges.The relevant indicators of scale applicability are assessed.The results show that in terms of sensitivity,NASA-TLX scale reaches the highest sensitivity(F=999.137,P=0<0.05).In terms of validity,NASA-TLX scale possesses the best concurrent validity(P=0.0255<0.05).In terms of diagnosticity,NASA-TLX scale based on 6 dimensions takes on the best diagnostic performance.In terms of subject acceptability,WP scale performs the worst.According to the analytic hierarchy process(AHP)model,the applicability scores of NASA-TLX scale,PAAS scale and WP scale are determined as 3,2.55 and 1.6714,respectively.Therefore,NASA-TLX scale is regarded as the most suitable subjective evaluation questionnaire for assembly workers,which is also an effective quantitative evaluation method for the cognitive load of assembly workers. 展开更多
关键词 assembly worker electroencephalogram(EEG) analytic hierarchy process(AHP) National Aeronautics and Space Administration Task load index(NASA-TLX)scale subjective evaluation scale applicability
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黄河流域河南段水资源空间均衡研究
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作者 焦士兴 岳欣 +4 位作者 王安周 张建伟 刘清春 尹义星 丁辉 《河北师范大学学报(自然科学版)》 CAS 2024年第3期217-224,共8页
基于水资源负载指数、水土资源匹配系数和用水效益系数等测算模型,研究了黄河流域河南段2011—2020年水资源空间均衡性.结果表明,黄河流域河南段8市水资源负载指数大致呈波动增长趋势且远大于10,水资源利用程度很高,基尼系数为0.31;水... 基于水资源负载指数、水土资源匹配系数和用水效益系数等测算模型,研究了黄河流域河南段2011—2020年水资源空间均衡性.结果表明,黄河流域河南段8市水资源负载指数大致呈波动增长趋势且远大于10,水资源利用程度很高,基尼系数为0.31;水土资源匹配系数大致呈波动下降趋势且平均值为0.33,水土匹配程度较低,基尼系数为0.28;用水效益系数呈稳步上升趋势,单方水GDP产值为208元,用水效益与经济发展水平相对合理,基尼系数为0.32;水资源空间均衡系数平均值为0.55,空间均衡等级为Ⅲ级,属于一般失衡.基于此,合理配置水资源、提高用水效率、提前规划引水调水等有利于促进黄河流域河南段社会经济和水资源利用空间均衡发展. 展开更多
关键词 黄河流域 空间均衡 负载指数 匹配系数 用水效益
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一种新型结构与保温一体化复合墙板节点试验
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作者 马少春 谷宇 鲍鹏 《防灾减灾工程学报》 CSCD 北大核心 2024年第2期396-403,共8页
为解决复合墙板节点常见的保温板易燃、易脱落等棘手问题,并使其抗震性能良好。给出了一种新型的结构与保温一体化陶粒混凝土T型复合墙板节点。该复合墙板节点具有夹芯独特构造优势,主要表现在绿色节能,轻质高强,力学性能好,保温系统连... 为解决复合墙板节点常见的保温板易燃、易脱落等棘手问题,并使其抗震性能良好。给出了一种新型的结构与保温一体化陶粒混凝土T型复合墙板节点。该复合墙板节点具有夹芯独特构造优势,主要表现在绿色节能,轻质高强,力学性能好,保温系统连接可靠,还能杜绝火灾的发生。通过对T型复合墙板节点进行抗震试验,分别研究了其滞回性能、破坏机理、承载及变形能力、延性、耗能、损伤等。结果表明:一体化复合墙板节点的破坏顺序为腹板-翼缘-节点核心区;薄弱位置主要发生在腹板脚部,混凝土被拉裂或压碎,钢筋被拉长或压弯等;节点核心区受力相对良好,安全储备充足;符合“强节点,弱构件”设计要求和墙板革新发展政策。延性系数大于3,墙板节点安全性能良好。通过损伤指标评估分析,了解了试件各阶段工作状态。 展开更多
关键词 结构与保温一体化 复合墙板节点 抗震试验 滞回及骨架曲线 损伤指标
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海陆交互相软土固结抗剪强度指标变化规律研究
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作者 刘红军 何程铃 +2 位作者 陈锋 周志军 杨超 《森林工程》 北大核心 2024年第4期218-224,共7页
以珠三角地区海陆交互相淤泥质软土为研究对象,通过室内直剪试验探究不同固结压力和固结度下抗剪强度及抗剪强度指标的变化规律,提出抗剪强度及对应指标-固结度-固结压力三维Logistic数学模型。研究结果表明,当固结压力P≥200 kPa、固结... 以珠三角地区海陆交互相淤泥质软土为研究对象,通过室内直剪试验探究不同固结压力和固结度下抗剪强度及抗剪强度指标的变化规律,提出抗剪强度及对应指标-固结度-固结压力三维Logistic数学模型。研究结果表明,当固结压力P≥200 kPa、固结度U≥40%时,软土黏聚力(c)和内摩擦角(φ)增长较为明显;当U=100%时,各级固结压力作用下的软土抗剪强度(τ)相较于初始状态分别提高了7.89、12.73、13.50、18.20、22.38 kPa;所给出的三维数学模型可直接计算出某一固结压力和固结度下的抗剪强度指标c、φ、τ。研究成果能够更为准确地评价该地区软土地基逐级加载过程中的整体稳定性。 展开更多
关键词 海陆交互相软土 分级加载 抗剪强度指标 固结度 固结压力
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大跨度钢-混结合梁悬索桥涡激振动控制指标体系研究
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作者 李永乐 朱金 +2 位作者 万田保 李涵 秦顺全 《桥梁建设》 EI CSCD 北大核心 2024年第2期22-30,共9页
为保证已建桥梁发生涡激振动后桥梁结构的安全以及桥上行车和行人安全,提出综合考虑人员舒适性、结构受力和停车线形三方面的大跨度钢-混结合梁悬索桥涡激振动控制指标体系。该体系包含9项指标,分别为驾乘人员舒适度、驾乘人员晕动症、... 为保证已建桥梁发生涡激振动后桥梁结构的安全以及桥上行车和行人安全,提出综合考虑人员舒适性、结构受力和停车线形三方面的大跨度钢-混结合梁悬索桥涡激振动控制指标体系。该体系包含9项指标,分别为驾乘人员舒适度、驾乘人员晕动症、行人舒适度(狄克曼指标)、加劲梁强度、加劲梁应力、加劲梁挠度、桥面纵坡、竖曲线半径和停车视距。以武汉鹦鹉洲长江大桥为背景,分别计算了“限速”和“封桥”2个交通管制措施下9项指标对应的涡激振动振幅限值。在此基础上,将9项指标对应的涡激振动振幅限值的最小值作为涡激振动限值建议取值。结果表明:当该桥发生低阶竖弯涡激振动(VS1、VAS1)时,涡激振动的控制因素为加劲梁挠度指标;当大桥发生VAS2模态的竖弯涡激振动时,涡激振动由驾乘人员晕动症指标和行人舒适度指标共同控制;当大桥发生高阶竖弯涡激振动(VAS3、VAS4)时,涡激振动由行人舒适度指标控制。涡激振动控制指标体系及限值标准的计算框架可适用于不同桥型涡激振动限值的计算。 展开更多
关键词 悬索桥 钢-混结合梁 涡激振动 控制指标体系 人员舒适性 结构受力 行车线形
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CTCA定量参数对冠心病患者短期病死预测价值
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作者 董小波 张仲慧 +1 位作者 郭庆乐 焦鹏飞 《临床误诊误治》 CAS 2024年第8期24-29,共6页
目的探讨CT冠状动脉造影(CTCA)定量参数对冠心病患者短期病死预测价值。方法选取2021年3月—2023年3月收治的冠心病200例,比较不同冠状动脉病变程度冠心病患者CTCA定量参数(动脉阻力指数、总斑块负荷和斑块最小密度CT值),分析CTCA定量... 目的探讨CT冠状动脉造影(CTCA)定量参数对冠心病患者短期病死预测价值。方法选取2021年3月—2023年3月收治的冠心病200例,比较不同冠状动脉病变程度冠心病患者CTCA定量参数(动脉阻力指数、总斑块负荷和斑块最小密度CT值),分析CTCA定量参数与冠心病患者冠状动脉病变程度相关性,探讨术后1年冠心病患者病死情况,分析CTCA定量参数与冠心病患者短期病死风险关联性,评价CTCA定量参数对冠心病患者短期病死预测价值。结果不同冠状动脉病变程度冠心病患者动脉阻力指数、总斑块负荷逐渐升高,斑块最小密度CT值逐渐降低(P<0.05)。冠心病患者动脉阻力指数、总斑块负荷与疾病类型、病变支数及狭窄程度呈正相关,斑块最小密度CT值与疾病类型、病变支数及狭窄程度呈负相关(P<0.05)。冠心病200例中39例(19.50%)术后1年病死。动脉阻力指数、总斑块负荷和斑块最小密度CT值与冠心病患者短期病死有关(P<0.01)。对冠心病患者短期病死预测的受试者工作特征曲线下面积动脉阻力指数、总斑块负荷和斑块最小密度CT值三者联合明显高于单独预测(P<0.05)。结论CTCA定量参数与冠心病患者冠状动脉病变程度密切相关,且联合各参数预测冠心病患者短期病死价值较高。 展开更多
关键词 冠心病 CT冠状动脉造影 定量参数 动脉阻力指数 总斑块负荷 斑块最小密度CT值 冠状动脉病变程度 病死
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血浆致动脉粥样硬化指数与脑小血管病总负荷的相关性研究进展
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作者 刘静 董爱勤 《中外医学研究》 2024年第14期177-180,共4页
脑小血管病(CSVD)是一组由不同病因造成的临床症状和影像学表现相似的疾病,它主要影响着脑内的小动脉及小静脉等高级血管网。目前,CSVD的病理生理机制仍不完全清楚,但动脉粥样硬化(AS)是众所周知的脑部血管疾病的主要病理机制之一,而血... 脑小血管病(CSVD)是一组由不同病因造成的临床症状和影像学表现相似的疾病,它主要影响着脑内的小动脉及小静脉等高级血管网。目前,CSVD的病理生理机制仍不完全清楚,但动脉粥样硬化(AS)是众所周知的脑部血管疾病的主要病理机制之一,而血脂在AS的发病机制中又起着非常重要的作用。随着大量学者的深入研究,目前认为血浆致动脉粥样硬化指数(AIP)及其相关传统血脂指标与CSVD联系密切。此研究从AIP与CSVD的发生发展入手,深入探讨了AIP及相关传统血脂指标与CSVD各分型之间的相关性,整合CSVD影像学总负荷来体现CSVD的严重程度,进一步探讨AIP及传统血脂指标与CSVD总负荷的相关性,最终确定了AIP与CSVD严重程度的相关性。本文对AIP及其相关传统指标与CSVD总负荷的相关性研究进展做一综述,全面阐述了血脂对CSVD总负荷的影响,为临床建立CSVD总负荷综合性评价指标提供新依据。 展开更多
关键词 血浆致动脉粥样硬化指数 脑小血管病 脑小血管病总负荷 血脂 综述
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自重及加载条件下絮凝剂调理废弃泥浆的脱水效果 被引量:2
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作者 韩超 俞越中 +4 位作者 柏彬 肖涵 范舟 吴巍 孙科 《长江科学院院报》 CSCD 北大核心 2024年第2期115-122,共8页
群桩基础、地下连续墙等施工会带来巨量的废弃泥浆,城市地下空间开发利用及盾构掘进过程会产生大量高含水率泥浆状的渣土,常规的堆场处理受限于成本和环境问题,需要对废弃泥浆进行高效脱水处理,减少废弃泥浆量。为研究絮凝剂调理废弃泥... 群桩基础、地下连续墙等施工会带来巨量的废弃泥浆,城市地下空间开发利用及盾构掘进过程会产生大量高含水率泥浆状的渣土,常规的堆场处理受限于成本和环境问题,需要对废弃泥浆进行高效脱水处理,减少废弃泥浆量。为研究絮凝剂调理废弃泥浆的脱水效果,提升泥浆脱水效率,采用单一、复合絮凝剂调理废弃泥浆,通过室内量筒沉积和小型堆载预压试验,对比研究絮凝剂类型和掺量配比对泥浆泥水分离效果的影响,并为脱水效果提供判断依据。结果表明:有机絮凝剂能够改善泥浆的脱水性能,提高泥水分离程度,且存在最优掺量;复合絮凝剂能够发挥有机、无机絮凝剂的协同作用,更进一步提升泥浆脱水程度,其中PAM类复合絮凝剂脱水性能优异,PAM与CaO复合絮凝剂组合处理泥浆时,其沉积层含水率降低程度能够达到82.75%。研究成果可为废弃泥浆的合理处置和资源化利用提供参考。 展开更多
关键词 泥浆 有机絮凝剂 复合絮凝剂 泥水分离 脱水效果 堆载预压 评价指标
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桥梁承载能力多水准可靠度评定方法
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作者 郑旭 伊廷华 +2 位作者 杨东辉 李宏男 周海俊 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第1期36-43,共8页
为在中国桥梁评定规范中引入“保守设计,非保守评定”的思想,提出一种“新-旧桥”两水准可靠度评定方法.对比分析了中、美桥梁评定规范分析检算公式、评定可靠指标和分项系数的异同,并将美国规范通过折减活载分项系数调整评定可靠度的... 为在中国桥梁评定规范中引入“保守设计,非保守评定”的思想,提出一种“新-旧桥”两水准可靠度评定方法.对比分析了中、美桥梁评定规范分析检算公式、评定可靠指标和分项系数的异同,并将美国规范通过折减活载分项系数调整评定可靠度的方法引入中国规范中.首先提出了将新桥设计可靠指标折减0.5作为旧桥评定可靠指标的方法,之后通过一次二阶矩方法对不同受力形式、不同荷载运营状况的评定活载分项系数进行校准,给出了“新桥1.4,旧桥1.2”的评定活载分项系数取值建议,最后通过一个RC简支T梁桥评定算例验证了方法的可行性.结果显示,所提出评定方法与规范方法相比最不利需求能力比降低了0.07,实现了在役旧桥的非保守评定. 展开更多
关键词 公路桥梁 承载能力评定 极限状态 可靠指标 分项系数
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