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Chinese Physics B 2020年第2期29卷 301-308页

作者：高广健邓明晰胡宁项延训 Department of Physics Army Logistics UniversityChongqing 401331China College of Aerospace Engineering Chongqing UniversityChongqing 400044China School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China

On the basis of second-order perturbation approximate and modal expansion approach,we investigate the enhancement effect of cumulative second-harmonic generation(SHG)of circumferential guided waves(CGWs)in a circular tube,which is inherently induced by the closed propagation feature of CGWs.An appropriate mode pair of primary-and double-frequency CGWs satisfying the phase velocity matching and nonzero energy flux is selected to ensure that the second harmonic generated by primary CGW propagation can accumulate along the circumference.Using a coherent superposition of multi-waves,a model of unidirectional CGW propagation is established for analyzing the enhancement effect of cumulative SHG of primary CGW mode selected.The theoretical analyses and numerical simulations performed directly demonstrate that the second harmonic generated does have a cumulative effect along the circumferential direction and the closed propagation feature of CGWs does enhance the magnitude of cumulative second harmonic generated.Potential applications of the enhancement effect of cumulative SHG of CGWs are considered and discussed.The theoretical analysis and numerical simulation perspective presented here yield an insight previously unavailable into the physical mechanism of the enhancement effect of cumulative SHG by closed propagation feature of CGWs in a circular tube.

关键词： circumferential guided wave second-harmonic generation(SHG) enhancement effect of cumulative SHG closed propagation feature

Feature Relationships Learning Incorporated Age Estimation Assisted by cumulative Attribute Encoding

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Computers, Materials & Continua 2018年第9期56卷 467-482页

作者： Qing Tian Meng Cao Tinghuai Ma School of Computer and Software Nanjing University of Information Science and TechnologyNanjing210044China Jiangsu Engineering Center of Network Monitoring Nanjing University of Information Science and TechnologyNanjing210044China School of Electrical and Electronic Engineering University of ManchesterManchesterM139PLUK

The research of human facial age estimation(AE)has attracted increasing attention for its wide applications.Up to date,a number of models have been constructed or employed to perform AE.Although the goal of AE can be achieved by either classification or regression,the latter based methods generally yield more promising results because the continuity and gradualness of human aging can naturally be preserved in age regression.However,the neighbor-similarity and ordinality of age labels are not taken into account yet.To overcome this issue,the cumulative attribute(CA)coding was introduced.Although such age label relationships can be parameterized via CA coding,the potential relationships behind age features are not incorporated to estimate age.To this end,in this paper we propose to perform AE by encoding the potential age feature relationships with CA coding via an implicit modeling strategy.Besides that,we further extend our model to gender-aware AE by taking into account gender variance in aging process.Finally,we experimentally validate the superiority of the proposed methodology.

关键词： Age estimation cumulative attribute gender-aware age estimation correlation relationship learning

Imputing missing values using cumulative linear regression

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CAAI Transactions on Intelligence Technology 2019年第3期4卷 182-200页

作者： Samih M. Mostafa Faculty of Science Mathematics DepartmentComputer ScienceSouth Valley UniversityQena 83523Egypt

The concept of missing data is important to apply statistical methods on the dataset. Statisticians and researchers may end up to an inaccurate illation about the data if the missing data are not handled properly. Of late, Python and R provide diverse packages for handling missing data. In this study, an imputation algorithm, cumulative linear regression, is proposed. The proposed algorithm depends on the linear regression technique. It differs from the existing methods, in that it cumulates the imputed variables;those variables will be incorporated in the linear regression equation to filling in the missing values in the next incomplete variable. The author performed a comparative study of the proposed method and those packages. The performance was measured in terms of imputation time, root-mean-square error, mean absolute error, and coefficient of determination (R^2). On analysing on five datasets with different missing values generated from different mechanisms, it was observed that the performances vary depending on the size, missing percentage, and the missingness mechanism. The results showed that the performance of the proposed method is slightly better.

关键词： Imputing missing values cumulative linear regression statistical methods

Entity Burst Discriminative Model for cumulative Citation Recommendation

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Journal of Beijing Institute of Technology 2019年第2期28卷 356-364页

作者： Lerong Ma College of Mathematics and Computer Science Yan’an University

Knowledge base acceleration-cumulative citation recommendation(KBA-CCR)aims to detect citation-worthiness documents from a chronological stream corpus for a set of target entities in a knowledge base.Most previous works only consider a number of semantic features between documents and target entities in the knowledge base,and then use powerful machine learning approaches such as logistic regression to classify relevant documents and non-relevant documents.However,the burst activities of an entity have been proved to be a significant signal to predict potential citations.In this paper,an entity burst discriminative model(EBDM)is presented to substantially exploit such burst features.The EBDM presents a new temporal representation based on the burst features,which can capture both temporal and semantic correlations between entities and documents.Meanwhile,in contrast to the bag-of-words model,the EBDM can significantly decrease the number of non-zero entries of feature vectors.An extensive set of experiments were conducted on the TREC-KBA-2012 dataset.The results show that the EBDM outperforms the performance of the state-of-the-art models.

关键词： knowledge base burst features cumulative citation recommendation discriminative model

cumulative impact of dam constructions on streamflow and sediment regime in lower reaches of the Jinsha River, China

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Journal of Mountain Science 2018年第12期15卷 2752-2765页

作者： HUANG Xiao-rong GAO Lin-yun YANG Peng-peng XI Yuan-yuan State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University College of Water Resource & Hydropower Sichuan University

The cumulative effect of cascade hydropower stations on river ecological environment has been widely concerned because of the significant streamflow hydrology change induced by dam constructions. The characteristics of the change in the lower reaches of the Jinsha River, China are analyzed based on long-term(1952–2015) hydrological and sedimentological data. The averaging coefficient, reservoir regulation coefficient(RRC), incoming sediment coefficient(ISC), and sediment transport modulus(STM), which reflect the variation of streamflow and sediment regimes, are defined and calculated. The results show that the construction and regulation of reservoirs reduces flow in flood season, increases flow in dry season, significantly altering the monthly discharge regimes. These alterations also led directly to changes in the timing of extreme flows at Pingshan Station. The monthly flow records at the basin outlet are reconstructed using stepwise regression, to reduce reservoir impacts. Comparisons of observed and reconstructed monthly flows demonstrate that the previous studies overestimated the cumulative effects of cascade reservoirs on flow processes. Furthermore, this study clearly illustrates that the reduction in sediment trapping and sediment transportation capacity together lead to the sharp reduction in annual sediment yield at the Pingshan Station. The earlier constructed reservoirs have more obvious effects on the ISC and STM than the more recent reservoirs and the effect of sediment trapping is related to reservoir location, on the main stream versus tributaries.

关键词： Cascade reservoirs cumulative effect Hydrological regime Sediment load Jinsha River

A cumulative Prospect Theory Based Counterterrorism Resource Allocation Method under Interval Values

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Journal of Systems Science and Systems Engineering 2019年第4期28卷 478-493页

作者： Bingfeng Ge Xiaoxiong Zhang Xiaolei Zhou Yuejin Tan College of Systems Engineering National University of Defense TechnologyChangsha 410073 China The Sixty-third Research Institute National University of Defense Technology Nanjing 210007 China

Strategic resource allocation into decision-making model plays a valuable role for the defender in mitigating damage and improving efficiency in military environments.In this paper,we develop a defensive resource allocation model based on cumulative prospect theory (CPT),which considers terrorists' psychological factors of decision-making in reality.More specifically,we extend existing models in the presence of multiple attributes and terrorists' deviations from rationality using a multi-attribute cumulative prospect theory.In addition,interval values are used to cope with uncertainties regarding gain and loss.Comparative studies are also carried out to demonstrate the differences among minmax,Nash equilibrium (NE),and traditional probability risk analysis (PRA) strategies.Results show that the defender's optimal defensive resource allocation will change along with terrorists' behaviors and the proposed model makes more sense compared with other traditional resource allocation strategies.

关键词： Counterterrorism resource allocation cumulative prospect theory multiple attributes interval value

cumulative radiation exposure from diagnostic imaging in intensive care unit patients

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World Journal of Radiology 2016年第4期8卷 419-427页

作者： Fiachra Moloney Daniel Fama Maria Twomey Ruth O'Leary Conor Houlihane Kevin P Murphy Siobhan B O'Neill Owen J O'Connor Dorothy Breen Michael M Maher Department of Radiology Cork University Hospital Department of Anesthesia Cork University Hospital

AIM:To quantify cumulative effective dose of intensive care unit(ICU)patients attributable to diagnostic imaging.METHODS:This was a prospective,interdisciplinary study conducted in the ICU of a large tertiary referral and level 1 trauma center.Demographic and clinical data including age,gender,date of ICU admission,primary reason for ICU admission,APACHE Ⅱ score,length of stay,number of days intubated,date of death or discharge,and re-admission data was collected on all patients admitted over a 1-year period.The overall radiation exposure was quantified by the cumulative effective radiation dose(CED)in millisieverts(mS v)and calculated using reference effective doses published by the United Kingdom National Radiation Protection Board.Pediatric patients were selected for subgroupanalysis.RESULTS:A total of 2737 studies were performedin 421 patients.The total CED was 1704 m Sv with a median CED of 1.5 mS v(IQR 0.04-6.6 mS v).Total CED in pediatric patients was 74.6 mS v with a median CED of 0.07 mS v(IQR 0.01-4.7 mS v).Chest radiography was the most commonly performed examination accounting for 83% of all studies but only 2.7% of total CED.Computed tomography(CT)accounted for 16% of all studies performed and contributed 97% of total CED.Trauma patients received a statistically significant higher dose [median CED 7.7 mS v(IQR 3.5-13.8 mS v)] than medical [median CED 1.4 m Sv(IQR 0.05-5.4 m Sv)] and surgical [median CED 1.6 mS v(IQR 0.04-7.5 mS v)] patients.Length of stay in ICU [OR = 1.12(95%CI:1.079-1.157)] was identified as an independent predictor of receiving a CED greater than 15 mS v.CONCLUSION:Trauma patients and patients with extended ICU admission times are at increased risk of higher CEDs.CED should be minimized where feasible,especially in young patients.

关键词： cumulative effective dose Pediatric patients Computed tomography Radiation dose Intensive care unit

Does Rapid Urbanization Trigger Significant Increase of cumulative Heavy Rains in China?

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Asian Agricultural Research 2019年第6期11卷 25-32页

作者： Feng KONG School of Public Policy and Management of Tsinghua University Center for Crisis Management Research Tsinghua University China Meteorological Administration Training Centre

Severe disasters caused by extreme precipitation events have attracted more and more attention. The relationship between climate change and extreme precipitation has become the hottest scientific frontier issue. The study of daily torrential rain observations from 659 meteorological stations in China from 1951 to 2010 shows that rapid urbanization may have triggered a significant increase in heavy rains in China. It reached following conclusions: China’s interdecadal heavy rainfall amount,rainy days and rain intensity increased significantly,with an increase of 68. 71%,60. 15% and 11. 52%,respectively. The increase in the number of stations was 84. 22%,84. 22% and 54. 48%,respectively. It showed time change of " rapid-slow-rapid increase" and spatial change of gradual increase from southeastern coast to central China,southwest,north China,and northeastern regions. Rapid urbanization factors,including secondary industry output( GDP2),urban population ratio( UP),annual average haze days( HD),are likely to be the main causes of the increase in heavy rains in China. Their explanations of the variance of heavy rainfall amount( HRA),rainy day( RD) and rain intensity( RI) in China reached 61. 54%,58. 48% and 65. 54%,respectively,of which only the explanation of variance of heavy rainfall amount,rainy days and rain intensity was as high as 25. 93%,22. 98%and 26. 64%,respectively. However,explanation of variance of climatic factors including WPSH( West Pacific Subtropical High),ENSO( El Ni1 o-Southern Oscillation) AMO( Atlantic Interdecadal Oscillation),and AAO( Antarctic Oscillation) was only 24. 30%,26. 23%,and 21. 92%,respectively. Compared with the rapid urbanization forcing factor,the impact of these climatic factors was only one third of the former. The panel data of China’s county-level total population and annual average of visibility days were significantly correlated with China’s interdecadal heavy rainfall amount,rainy days and rain intensity. Their spatial correlation coefficient increased gradually from 1951-

关键词： cumulative heavy rain Human activities Urbanization Triggering factors Spatial and temporal pattern China

The Impact of Meteorological Factors on the Short-term cumulative Effect of Air Particulate in Tianjin

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Meteorological and Environmental Research 2019年第2期10卷 27-32,40页

作者： Wang Wei Liu Lili Wang Yan Tianjin Institute of Meteorological Science Tianjin Weather Modification Office

In order to reveal the rapid increase mechanism of particulate concentration in short time,a notion of short-term cumulative effect of air particulate is defined as the significant increase of pollutant concentration in a short time under the condition of breeze,stable weather and constant emission caused by human being's activities. Subsequently,an index of short-term cumulative effect is established with air diffusive equation,and then the macro-scale meteorological situation and micro-scale factors of forming the short-term cumulative effect are discussed with the observation data. The macro-scale meteorological variables contain upper-level weather situations and surface weather situations. The micro-scale factors mainly include the boundary-layer height and boundary-layer stability. The analyses show that boundary-layer factors and weather variables have a significant influence on the short-term cumulative effect. The notion of short-term cumulative effect will play an important role in interpreting the severe pollution weather.

关键词： Air particulate Short-term cumulative Effect Meteorological factor cumulative index

An Improved Group Decision-Making Model for the Investment Options of Small-Scale Photovoltaic Systems Based on cumulative Prospect Theory and Choquet Integral

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Wuhan University Journal of Natural Sciences 2019年第6期24卷 515-518页

作者： LIU Jicheng FU Xiaoxu XU Fangqiu WANG Zhenzhen LUO Cuicui School of Economics and Management North China Electric Power UniversityBeijing 102206China Beijing Key Laboratory of New Energy and Low-Carbon Development North China Electric Power UniversityBeijing 102206China Department of Mathematics University of TorontoToronto M5S 1A1ONCanada

With the development of photovoltaic(PV) industry, installing small-scale PV systems which are integrated into the buildings becomes popular. Therefore, it is important to make optimal investment decisions for investors and consumers. This paper proposes an improved group decision-making method which integrates the cumulative prospect theory and Choquet integral for the investment options of small-scale PV systems. From the perspective of sustainability, the alternatives are evaluated by four criteria, including economic benefits, solar energy condition, carbon emissions and social benefits. Since the performances of criteria are given by decision makers as linguistic variables, the proposed method measures the criteria values by intuitionistic trapezoidal fuzzy numbers. Then the alternatives are evaluated and ranked to determine the optimal option. Finally, the proposed method is implemented in a case study to illustrate its feasibility and effectiveness.

关键词： investment options small-scale photovoltaic systems cumulative prospect theory Choquet integral intuitionistic trapezoidal fuzzy numbers