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Change Trend of Chinese Urban Residents' Food-nitrogen Consumption 被引量:2
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作者 王俊能 许振成 彭晓春 《Agricultural Science & Technology》 CAS 2010年第4期176-179,共4页
Change trend of Chinese urban residents' per capita food-nitrogen annual consumption from 1981 to 2007 was analyzed and predicted by using ARIMA time-series model in order to reveal the change of urban food-nitrogen ... Change trend of Chinese urban residents' per capita food-nitrogen annual consumption from 1981 to 2007 was analyzed and predicted by using ARIMA time-series model in order to reveal the change of urban food-nitrogen consumption during the China's urbanization process.Results showed that after 1980s,the annual consumption of Chinese urban residents' food-nitrogen had a change trend of " increase-decrease-increase" and generally presented as a slight increasing trend;With the acceleration of rapid economic development and urbanization process,Chinese urban residents' food-nitrogen consumption will still keep a rising trend in future,and also has a large rising space. 展开更多
关键词 Food consumption NITROGEN spearman's rank correlation coefficient ARIMA model Urban residents China
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基于线性密集台阵的2023年甘肃积石山M_(S)6.2地震断层低速带研究
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作者 吴柏辰 秦满忠 +3 位作者 郭晓 王亚红 孙点峰 温淑琳 《地震工程学报》 CSCD 北大核心 2024年第3期734-741,共8页
2023年12月18日,甘肃省积石山县发生M_(S)6.2逆冲型地震。该地震发生在祁连活动地块拉脊山北缘断裂带,在断裂两侧曾发生过20余次5级左右中强地震,地震活动频次高,因此研究拉脊山断裂带特征具有重要意义。根据拉脊山断裂走向和此次地震... 2023年12月18日,甘肃省积石山县发生M_(S)6.2逆冲型地震。该地震发生在祁连活动地块拉脊山北缘断裂带,在断裂两侧曾发生过20余次5级左右中强地震,地震活动频次高,因此研究拉脊山断裂带特征具有重要意义。根据拉脊山断裂走向和此次地震余震分布,在刘集乡布设一条线性密集台阵,利用不同方位的余震事件计算体波的走时延时和放大效应。结果表明,P波和S波分别存在6个采样点(约0.012 s)和15个采样点(约0.03 s)的走时延时,推断出台阵西侧存在一个约150 m宽近似垂直的断层低速带,且该结果与远震P波相似性系数矩阵结果一致。 展开更多
关键词 甘肃积石山M_(s)6.2地震 走时延时 体波放大效应 线性密集台阵 断层低速带
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基于零模行波S变换时频矩阵的配电网单相接地故障定位方法
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作者 杨小磊 袁明哲 邹经鑫 《电力科学与技术学报》 CAS CSCD 北大核心 2024年第4期93-101,共9页
为提高配电网发生单相接地故障时的定位精度,提出一种基于电压零模行波S变换时频矩阵的选线和定位方法。首先,将各条馈线末端行波检测装置测得的行波信号解耦,得到故障电压零模行波;然后,在主馈线、一级和二级分支支路等特殊位置设置故... 为提高配电网发生单相接地故障时的定位精度,提出一种基于电压零模行波S变换时频矩阵的选线和定位方法。首先,将各条馈线末端行波检测装置测得的行波信号解耦,得到故障电压零模行波;然后,在主馈线、一级和二级分支支路等特殊位置设置故障,得到对应故障位置的S变换时频矩阵,建立确定故障支路的对比库;最后,将故障零模电压行波S变换时频矩阵与对比库中数据进行相似度对比,确定单相接地故障发生的馈线和所在支路,针对不同性质支路选取适应性最优的定位方法,实现配电网单相接地故障的精确定位。仿真结果表明:该方法的定位准确度高,且无须全网配备行波检测装置便能够实现配电网单相接地故障的精确定位。 展开更多
关键词 配电网 行波定位 s变换 矩阵相似度
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Teaching Ultrasound Imaging for Central Line Placement—A Resident’s Perspective
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作者 Jayanta Mukherji Nil Ural +1 位作者 Taqdees Sheikh W. Scott Jellish 《Open Journal of Anesthesiology》 2013年第5期263-271,共9页
The availability of ultrasound (US) devices has refined techniques for vascular access. The resident trainee’s ability to learn US techniques depends upon device availability, skills, and motivation of instructors. W... The availability of ultrasound (US) devices has refined techniques for vascular access. The resident trainee’s ability to learn US techniques depends upon device availability, skills, and motivation of instructors. We hypothesized that hands-on teaching program of US techniques for vascular access would have a positive impact on the trainee’s perceptions. After IRB approval, PGY3 anesthesiology residents with limited prior experience in US-guided vascular access underwent close supervision by attending staff as they performed US-guided Internal Jugular Vein (IJV) central line placements. A total of 66 land mark (LM) and 75 US-guided IJV cannulation performed by 19 residents were supervised. Residents completing the study were more proactive with 68.4% agreeing to use US based techniques for an anticipated difficulty in accessing central lines. The graduating residents involved in the study all strongly agreed that US imaging for vascular access was within the scope of practice of all anesthesiologists, and that training guidelines be established and incorporated in their practice. Fifty eight percent of residents stated that their confidence and skill levels had significantly improved. Teaching US-guided techniques resulted in an increase employment of such techniques by graduating residents with no impediment attributed to knowledge deficits or inexperience. Residents were more proactive with using US for anticipated difficulty in IJV placement. A short neck, poor landmark, anticoagulation, morbid obesity favored US use by residents. Systematic teaching of US techniques is justified as it significantly improves the resident’s perceptions and confidence. 展开更多
关键词 ULTRAsOUND-GUIDED Technique VAsCULAR Access GUIDELINEs residents PERCEPTION
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A Survey of cash Income of China's Rural Residents
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《China Population Today》 1998年第Z2期29-29,共1页
关键词 DOWN A survey of cash Income of China’s Rural residents
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具有饱和恢复率的SEIR时滞模型的行波解
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作者 卫珍妮 《西北师范大学学报(自然科学版)》 2024年第1期20-29,共10页
研究一类具有饱和恢复率的SEIR时滞模型的行波解.首先,考虑一类二维系统初值问题的适定性;然后,通过构造一对有界的向量值上、下解得到一个闭凸集;最后,利用Schauder不动点定理证明:当基本再生数R^(0)>1,波速c>c^(*)时模型存在非... 研究一类具有饱和恢复率的SEIR时滞模型的行波解.首先,考虑一类二维系统初值问题的适定性;然后,通过构造一对有界的向量值上、下解得到一个闭凸集;最后,利用Schauder不动点定理证明:当基本再生数R^(0)>1,波速c>c^(*)时模型存在非平凡行波解. 展开更多
关键词 sEIR模型 饱和恢复率 时滞 行波解 sCHAUDER不动点定理
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Per Capita Net Income of China's Rural Residents
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《China Population Today》 1998年第Z2期30-30,共1页
关键词 Per Capita Net Income of China’s Rural residents
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Per Capita Disposable Income of China's Urban Residents
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《China Population Today》 1998年第Z2期30-30,共1页
关键词 Per Capita Disposable Income of China’s Urban residents
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A Survey of 1997 Income and Expenditure of China's Urban Residents
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《China Population Today》 1998年第Z2期27-28,共2页
关键词 A survey of 1997 Income and Expenditure of China’s Urban residents
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TOD residents' attitudes toward walking to transit station: a case study of transit-oriented developments(TODs) in Bangkok,Thailand
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作者 Pornraht Pongprasert Hisashi Kubota 《Journal of Modern Transportation》 2019年第1期39-51,共13页
The study aims to analyze the attitude toward walking to the stations of residents living within 1 km of transit stations, or they are called transit-oriented development(TOD) residents. They are highly expected to wa... The study aims to analyze the attitude toward walking to the stations of residents living within 1 km of transit stations, or they are called transit-oriented development(TOD) residents. They are highly expected to walk to transit station and use rail in their daily travel. In this research, 249 respondents are asked 10 questions on attitudes of walking to station. The analysis was conducted in two stages: factor analysis and structural equation model. As the current access mode of respondents,walkers are more likely to be low-income households.People using motorized mode are mostly from middle-to high-income, households the largest group of respondents.For walking acceptance, high-income group accepts distance and time shorter than other incomes. Low-income households can accept the longer walking distance but shorter time. Middle-income households are more likely to walk in shorter distance than lower-income households,but they tend to accept longer walking time than others.As for the analysis results, the feeling of walking among all respondents significantly influences the walking acceptance. The benefit of walking significantly influences walking acceptance only among middle-income households. The walking attitudes on convenience, safety, a sense of freedom, healthiness, and environmental friendliness highly affect respondents' acceptable walking distance and time in TODs. 展开更多
关键词 ATTITUDE WALKING TOD residents WALKING acceptance travel-related ATTITUDE Transit-oriented development
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Manual Order Picking Route Optimization in Distribution Warehouse of Chain Furniture Retail Enterprise
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作者 Yongzhen Zeng Junkun Wang +1 位作者 Ching-Kuei Kao King-Zoo Tang 《American Journal of Operations Research》 2024年第3期105-136,共32页
Due to the effects of the COVID-19 pandemic and the rise of online shopping, the offline sales of IKEA Fuzhou have been declining since 2020. Because the cost of distribution warehouse is a major expense for offline c... Due to the effects of the COVID-19 pandemic and the rise of online shopping, the offline sales of IKEA Fuzhou have been declining since 2020. Because the cost of distribution warehouse is a major expense for offline chain furniture retailers, and the picking process is a key activity in distribution warehouse operations. To reduce the cost of distribution warehouse and alleviate the survival pressure of the offline chain furniture retailers, this paper focuses on optimizing the picking route of the IKEA Fuzhou distribution warehouse. It starts by creating a two-dimensional coordinate system for the storage location of the distribution warehouse using the traditional S-type picking strategy to calculate the distance and time of the sorting route. Then, the problem of optimizing the picking route is then transformed into the travelling salesman problem (TSP), and picking route optimization model is developed using a genetic algorithm to analyze the sorting efficiency and picking route optimization. Results show that the order-picking route using the genetic algorithm strategy is significantly better than the traditional S-type picking strategy, which can improve overall sorting efficiency and operations, reduce costs, and increase efficiency. Thus, this establishes an implementation process for the order-picking path based on genetic algorithm optimization to improve overall sorting efficiency and operations, reduce costs, increase efficiency, and alleviate the survival pressure of pandemic-affected enterprises. 展开更多
关键词 s-shaped Picking strategy Picking Route traveling salesman Problem Genetic Algorithm
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Love Is Intensified by Absence- Book Review on "The Time Traveler's Wife"
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作者 钟晓菁 《海外英语》 2012年第7X期225-226,共2页
In this paper,a review was finished according to a novel-"The Time Traveler's Wife".It use time travel to explore miscommunication and distance in relationships.A lot of knowledge could be obtained from ... In this paper,a review was finished according to a novel-"The Time Traveler's Wife".It use time travel to explore miscommunication and distance in relationships.A lot of knowledge could be obtained from the passage. 展开更多
关键词 BOOK REVIEW The Time traveler’s WIFE Miscommunicat
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Denial of Sartre's Existentialism in The Time Traveler's Wife
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作者 牛丽军 《海外英语》 2016年第17期163-165,共3页
By contrast with Sartre's existentialism,The Time Traveler's Wife depicts another humanistic world.Moreover,such things as meaning,reason,compensation and peace are indispensable in this world.
关键词 the time traveler’s wife sARTRE EXIsTENTIALIsM
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REMARK ON CRITICAL SPEED OF TRAVELING WAVEFRONTS FOR NICHOLSON'S BLOWFLIES EQUATION WITH DIFFUSION 被引量:2
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作者 危地 吴教育 梅铭 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1561-1566,共6页
This note is devoted to the son's blowflies equation with diffusion, a critical speed of traveling waves, we give behavior with respect to the mature age study on the traveling wavefronts to the Nicholtime-delayed re... This note is devoted to the son's blowflies equation with diffusion, a critical speed of traveling waves, we give behavior with respect to the mature age study on the traveling wavefronts to the Nicholtime-delayed reaction-diffusion equation. For the a detailed analysis on its location and asymptotic 展开更多
关键词 Nicholson's blowflies equation traveling wavefronts critical wave-speed
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Analysis of Satire in Jonathan Swift’s Gulliver’s Travels
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作者 陈俊 《海外英语》 2012年第18期181-182,188,共3页
As one of Jonathan Swift masterpieces, Gulliver's Travels chronicles Lemuel Gulliver's four odd voyages in the form of a travel log. With sharp satire, Swift ridicules vices of England and the whole Europe in ... As one of Jonathan Swift masterpieces, Gulliver's Travels chronicles Lemuel Gulliver's four odd voyages in the form of a travel log. With sharp satire, Swift ridicules vices of England and the whole Europe in the early 18th century. The article ana lyzes the art and specific usage of satiric techniques in Gulliver's Travels. 展开更多
关键词 sATIRE jonathan sWIFT Gulliver’s travels
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China’s National Image in Western Travel Writings in the Age of Discovery
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作者 LI Chaojun 《Journal of Landscape Research》 2019年第3期75-77,81,共4页
Western travel writings about China provided material driving and theoretical guidance for the Age of Discovery, and became the main spiritual motive of the Westerners voyage to the East. In the Age of Discovery, the ... Western travel writings about China provided material driving and theoretical guidance for the Age of Discovery, and became the main spiritual motive of the Westerners voyage to the East. In the Age of Discovery, the image of China in the eyes of Western envoys, merchants and missionaries begun to fade away from traditional mythological and psychedelic colors, and the image of cultural elements such as material, spirit and history become clear. These Western travelers tried to shape the image of China as a state of civilization and wisdom, a state of moral order, and a state of wealth and power. On the basis of the continued description of the kingship and wealth of the Middle Ages, they constructed an overall image of China as a powerful state of civilization and wealth, thus forming a new frame of reference for cognition of China. 展开更多
关键词 Age of DIsCOVERY travel writings China’s IMAGE
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Pointwise Estimates on Travelling Wave Solution of the Scalar Viscous Conservation Laws
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作者 Fu Yu-xia, Wang Wei-keSchool of Mathematics and Statistics, Wuhan University, Wuhan 430072, Hubei,China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第02A期335-341,共7页
This paper research on the pointwise behavior of perturbations from a viscous shock solution to a scalar viscous conservation law by introducing an approximate Green’s function. The authors obtain not only the pointw... This paper research on the pointwise behavior of perturbations from a viscous shock solution to a scalar viscous conservation law by introducing an approximate Green’s function. The authors obtain not only the pointwise decay of the perturbation and but also the high derivative of it. Stability in anyL(p≥1) norm is a direct consequence. 展开更多
关键词 scalar viscous conservation law travelling wave approximate Green’s function pointwise decay
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Traveling Wavefronts on Reaction Diffusion Systems with Spatio-Temporal Delays
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作者 Xinli Han Lijun Pan 《Applied Mathematics》 2013年第9期1278-1286,共9页
By using Schauder’s Fixed Point Theorem, we study the existence of traveling wave fronts for reaction-diffusion systems with spatio-temporal delays. In our results, we reduce the existence of traveling wave fronts to... By using Schauder’s Fixed Point Theorem, we study the existence of traveling wave fronts for reaction-diffusion systems with spatio-temporal delays. In our results, we reduce the existence of traveling wave fronts to the existence of an admissible pair of upper solution and lower solution which are much easier to construct in practice. 展开更多
关键词 schauder’s Fixed Point THEOREM travelING Wave FRONTs REACTION-DIFFUsION sPATIO-TEMPORAL DELAYs
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The Mixture Japanese and Western Style in the Image of theGovernor-General’s Residence of Taiwan Under Japanese Rule 1
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作者 Lee Chao-Ying 《Journal of Literature and Art Studies》 2019年第11期1099-1129,共31页
This paper focused on Japan who was as a new colonial government in Taiwan under Japanese rule,during the period of which took official buildings or urban planning mainly of a series of Western European-style architec... This paper focused on Japan who was as a new colonial government in Taiwan under Japanese rule,during the period of which took official buildings or urban planning mainly of a series of Western European-style architecture as a ruler’s cultural identity and a modern Taiwan policy.However,in the context of East Asian modernity,the basic colonial not only mixed Eurocentric,but also included Japan Center and the interaction between the two.Therefore,the scope of research and discussion shall have regarded to the non-Western,non-white nature of the Japanese Empire,and its colonial/modernity construction is another new model.Taiwan Governor-General’s Residence as the Governor-General’s residence for Japanese government combined administrative office,daily living,and social life,showing a symbol of Japan’s colonial ruling class,and a hostel to greet Japanese royal family and the nobility from time to time.As a mansion of both Western Baroque and Japanese style,its architectural design has class meaning,therefore it featured with a class-separation building,also combined the leisure of Western high society.The associated festivals at that time included tea party,fairs and royal family welcoming pilgrimage,the part of which with a strong political implication.This paper mainly uses the images of the Taiwan Governor-General’s Residence during the Japanese rule period and the literature at that time to restore the mixed taste and Japanese-Western style of Taiwan at that time.The Japanese colonists ruled the complex interactions of different ethnic groups in Taiwan. 展开更多
关键词 COLONIAL TAIWAN Governor-General’s residENCE Japanese-Western style IMAGE
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Observations and modelling of the travel time delay and leading negative phase of the 16 September 2015 Illapel,Chile tsunami
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作者 Peitao Wang Zhiyuan Ren +4 位作者 Lining Sun Jingming Hou Zongchen Wang Ye Yuan Fujiang Yu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第11期11-30,共20页
The systematic discrepancies in both tsunami arrival time and leading negative phase(LNP)were identified for the recent transoceanic tsunami on 16 September 2015 in Illapel,Chile by examining the wave characteristics ... The systematic discrepancies in both tsunami arrival time and leading negative phase(LNP)were identified for the recent transoceanic tsunami on 16 September 2015 in Illapel,Chile by examining the wave characteristics from the tsunami records at 21 Deep-ocean Assessment and Reporting of Tsunami(DART)sites and 29 coastal tide gauge stations.The results revealed systematic travel time delay of as much as 22 min(approximately 1.7%of the total travel time)relative to the simulated long waves from the 2015 Chilean tsunami.The delay discrepancy was found to increase with travel time.It was difficult to identify the LNP from the near-shore observation system due to the strong background noise,but the initial negative phase feature became more obvious as the tsunami propagated away from the source area in the deep ocean.We determined that the LNP for the Chilean tsunami had an average duration of 33 min,which was close to the dominant period of the tsunami source.Most of the amplitude ratios to the first elevation phase were approximately 40%,with the largest equivalent to the first positive phase amplitude.We performed numerical analyses by applying the corrected long wave model,which accounted for the effects of seawater density stratification due to compressibility,self-attraction and loading(SAL)of the earth,and wave dispersion compared with observed tsunami waveforms.We attempted to accurately calculate the arrival time and LNP,and to understand how much of a role the physical mechanism played in the discrepancies for the moderate transoceanic tsunami event.The mainly focus of the study is to quantitatively evaluate the contribution of each secondary physical effect to the systematic discrepancies using the corrected shallow water model.Taking all of these effects into consideration,our results demonstrated good agreement between the observed and simulated waveforms.We can conclude that the corrected shallow water model can reduce the tsunami propagation speed and reproduce the LNP,which is observed for tsunamis that have propagated over long distances frequently.The travel time delay between the observed and corrected simulated waveforms is reduced to<8 min and the amplitude discrepancy between them was also markedly diminished.The incorporated effects amounted to approximately 78%of the travel time delay correction,with seawater density stratification,SAL,and Boussinesq dispersion contributing approximately 39%,21%,and 18%,respectively.The simulated results showed that the elastic loading and Boussinesq dispersion not only affected travel time but also changed the simulated waveforms for this event.In contrast,the seawater stratification only reduced the tsunami speed,whereas the earth’s elasticity loading was responsible for LNP due to the depression of the seafloor surrounding additional tsunami loading at far-field stations.This study revealed that the traditional shallow water model has inherent defects in estimating tsunami arrival,and the leading negative phase of a tsunami is a typical recognizable feature of a moderately strong transoceanic tsunami.These results also support previous theory and can help to explain the observed discrepancies. 展开更多
关键词 2015 Chilean tsunami travel time delay leading negative phase numerical modeling corrected long wave earth’s elasticity loading seawater density stratification Boussinesq dispersion
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