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Ripple-effect analysis for operational architecture of air defense systems with supernetwork modeling

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Journal of Systems Engineering and Electronics 2014年第2期25卷 249-264页

作者： Zhigang Zou Fuxian Liu Shiman Sun Lu Xia Chengli Fan School of air and Missile Defense Air Force Engineering University Research & Development center China Airport Construction Group Corporation

In order to solve the problem that the ripple-effect analy- sis for the operational architecture of air defense systems （OAADS） is hardly described in quantity with previous modeling approaches, a supernetwork modeling approach for the OAADS is put for- ward by extending granular computing. Based on that operational units and links are equal to different information granularities, the supernetwork framework of the OAADS is constructed as a “four- network within two-layer” structure by forming dynamic operating coalitions, and measuring indexes of the ripple-effect analysis for the OAADS are given combining with Laplace spectral radius. In this framework, via analyzing multidimensional attributes which inherit relations between operational units in different granular scales, an extended granular computing is put forward integrating with a topological structure. Then the operation process within the supernetwork framework, including transformation relations be- tween two layers in the vertical view and mapping relations among functional networks in the horizontal view, is studied in quantity. As the application case shows, comparing with previous modeling approaches, the supernetwork model can validate and analyze the operation mechanism in the air defense architecture, and the ripple-effect analysis can be used to confirm the key operational unit with micro and macro viewpoints.

关键词： operational architecture air defense system super-network model Laplace spectral radius ripple-effect analysis.

A modified vegetation water supply index(MVWSI) and its application in drought monitoring over Sichuan and Chongqing, China

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Journal of Integrative Agriculture 2016年第9期15卷 2132-2141页

作者： WU Men-xin LU Hou-quan National meteorological center China Meteorological Administration

Based on the principle of vegetation water supply index（VWSI）, relative normalized difference vegetation index（RNDVI） and relative land surface temperature（RLST） are proposed, with which a modified vegetation water supply index（MVWSI） is constructed, i.e.,MVWSI=RNDVI/RLST^2. Compared with VWSI, MVWSI eliminates the difference caused by the spatial and temporal distribution of VWSI. MVWSI was applied to monitor drought over Sichuan and Chongqing, China in 2006, suggesting that MVWSI can demonstrate the whole process of drought from its emergence and development to its weakening and disappearance. The relative precipitation index（RPI） is used to examine the effectiveness of MVWSI. The examination result shows that MVWSI and RPI have high consistency in spatial distribution and in-site time series analysis. Compared with vegetation condition index（VCI）, temperature condition index（TCI）, vegetation temperature condition index（VTCI） and temperature vegetation drought index（TVDI）, MVWSI is simpler in calculation and more stable hence more easily realized in application.

关键词： MVWSI drought NDVI LST

Influence of Changes in Solar Radiation on Changes of Surface Temperature in China

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Acta meteorologica Sinica 2013年第1期27卷 87-97页

作者：张华尹青 Teruyuki NAKAJIMA Nakata Mukai MAKIKO 卢鹏何金海 Laboratory for Climate Studies National Climate CenterChina Meteorological Administration meteorological center of air force in Beijing Military Area Nanjing University of Information Science & Technology center for Earth Surface System Dynamics Atmosphere and Ocean Research InstituteUniversity of Tokyo Kinki University

The long-term trends of total surface solar radiation （SSR）, surface diffuse radiation, and surface air temperature were analyzed in this study based on updated 48-yr data from 55 observational stations in China, and then the correlation between SSR and the diurnal temperature range （DTR） was studied. The effect of total solar radiation on surface air temperature in China was investigated on the basis of the above analyses. A strong correlation between SSR and DTR was found for the period 1961-2008 in China. The highest correlation and steepest regression line slope occurred in winter, indicating that the solar radiation effect on DTR was the largest in this season. Clouds and water vapor have strong influences on both SSR and DTR, and hence on their relationship. The largest correlations between SSR and DTR occurred in wintertime in northern China, regardless of all-day （including clear days and cloudy days） or clear-day cases. Our results also showed that radiation arriving at the surface in China decreased significantly during 1961-1989 （dimming period）, but began to increase during 1990 2008 （brightening period）, in agreement with previous global studies. The reduction of total SSR offset partially the greenhouse warming during 1961-1989. However, with the increase of SSR after 1990, this offsetting effect vanished; on the contrary, it even made a contribution to the accelerated warming. Nonetheless, the greenhouse warming still played a controlling role because of the increasing of minimum and mean surface temperatures in the whole study period of 1961-2008. We estimated that the greenhouse gases alone may have caused surface temperatures to rise by 0.31-0.46℃ （10 yr）^-1 during 1961-2008, which is higher than previously estimated. Analysis of the corresponding changes in total solar radiation, diffuse radiation, and total cloud cover indicated that the dimming and brightening phenomena in China were likely attributable to increases in absorptive and scattering

关键词： global dimming/brightening global warming surface solar radiation surface air temperature

Using Moving North Pacific Index to Improve Rainy Season Rainfall Forecast over the Yangtze River Basin by Analog Error Correction

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Journal of meteorological Research 2015年第4期29卷 627-638页

作者：支蓉王启光封国林冯爱霞 Laboratory for Climate Studies National Climate Center China Meteorological Administration China meteorological Administration Training center China Meteorological Administration National meteorological Information center China Meteorological Administration

A new analog error correction （AEC） scheme based on the moving North Pacific index （MNPI） is designed in this study. This scheme shows obvious improvement in the prediction skill of the operational coupled general circulation model （CGCM） of the National Climate center of China for the rainy season rainfall （RSR） anomaly pattern correlation coefficient （ACC） over the mid-to-lower reaches of the Yangtze River （MLRYR）. A comparative analysis indicates that the effectiveness of the new scheme using the MNPI is better than the system error correction scheme using the North Pacific index （NPI）. A Euclidean distance- weighted mean rather than a traditional arithmetic mean, is applied to the integration of the analog year＇s prediction error fields. By using the MNPI AEC scheme, independent sample hindcasts of RSR during the period 2003-2009 are then evaluated. The results show that the new scheme exhibited a higher forecast skill during 2003-2009, with an average ACC of 0.47; while the ACC for the NPI case was only 0.19. Furthermore, the forecast skill of the RSR over the MLRYR is examined. In the MNPI case, empirical orthogonal function （EOF） was used in the degree compression of the prediction error fields from the CCCM, whereas the AEC scheme was applied only to its first several EOF components for which the accumulative explained variance accounted for 80% of the total variance. This further improved the ACC of the independent sample hindcasts to 0.55 during the 7-yr period.

关键词： moving North Pacific index (MNPI) rainy season rainfall (RSR) mid-to-lower reaches of the Yangtze River (MLRYR) weighted analog error correction (AEC) degree compression

Modification of Cumulus Convection and Planetary Boundary Layer Schemes in the GRAPES Global Model

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Journal of meteorological Research 2015年第5期29卷 806-822页

作者：刘琨陈起英孙健 National meteorological center China Meteorological Administration Numerical Weather Prediction center of China meteorological Administration

Cumulus convection is a key linkage between hydrological cycle and large-scale atmospheric circulation. Cumulus parameterization scheme is an important component in numerical weather and climate modeling studies. In the Global/Regional Assimilation and Prediction Enhanced System （GRAPES）, turbulent mixing and diffusion approach is applied in its shallow convection scheme. This method overestimates the vertical transport of heat and moisture fluxes but underestimates cloud water mixing ratio over the region of stratocumulus clouds. As a result, the simulated low stratocumulus clouds are less than observations. To overcome this problem, a mass flux method is employed in the shallow convection scheme to replace the original one. Meanwhile, the deep convection scheme is adjusted correspondingly. This modification is similar to that in the US NCEP Global Forecast System （GFS）, which uses the simplified Arakawa Schubert Scheme （SAS）. The planetary boundary layer scheme （PBL） is also revised by considering the coupling between the PBL and stratocumulus clouds. With the modification of both the cumulus and PBL schemes, the GRAPES simulation of shallow convective heating rate becomes more reasonable; total amounts of stratocumulus clouds simulated over the eastern Pacific and their vertical structure are more consistent with observations; the underestimation of stratocumulus clouds simulated by original schemes is less severe with the revised schemes. Precipitation distribution in the tropics becomes more reasonable and spurious precipitation is effectively suppressed. The westward extension and northward movement of the western Pacific subtropical high simulated with the revised schemes are more consistent with Final Operational Global Analysis （FNL） than that simulated with the original schemes. The statistical scores for the global GRAPES forecast are generally improved with the revised schemes, especially for the simulation of geopotential height in the Northern Hemisphe

关键词： GRAPES model cumulus parameterization boundary layer diffusion mass flux

A Comparison of Atmospheric Temperature over China between Radiosonde Observations and Multiple Reanalysis Datasets

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Journal of meteorological Research 2016年第2期30卷 242-257页

作者：郭艳君张思齐颜京辉陈哲阮新 National Climate center China Meteorological Administration National meteorological Information center China Meteorological Administration

The quality controlled（RAW） and homogenized（ADJ） radiosonde temperatures within 850-30 hPa collected at 118 stations in China are compared,on a monthly mean basis,with the temperatures extracted from 8 reanalysis datasets（REA） including NCEP-1,NCEP-2,ERA-40（ECMWF 45-yr Reanalysis）,ERAInterim,JRA-55（Japanese 55-yr Reanalysis）,20CR（20th Century Reanalysis）,MERRA（Modern Era Retrospective-Analysis）,and CFSR（Climate Forecast System Reanalysis）.Average differences,correlations,standard deviations,and linear trends among RAW,ADJ,and REA for the period 1981-2010 are *** results reveal significant inhomogeneity in the time series of RAW radiosonde temperature in China;an overall negative adjustment was thus employed to obtain the ADJ temperatures,and the effect of the negative adjustment is the most significant within 200-100 *** a homogenization process has removed the system errors in RAW,possibly caused by radiosonde instrument changes and observation system ***,the correlation is higher between ADJ and REA than that between RAW and *** mean difference between ADJ and REA is about 1℃ during 1981-2010,while REA are mostly cooler in the troposphere and warmer in the stratosphere than ADJ;nonetheless,they have a significant high and positive correlation and their annual variability is notably ***,the linear trends in REA and ADJ both demonstrate warming in the lower-mid troposphere and cooling in the mid stratosphere,with large uncertainties found in the upper troposphere and lower *** general,ERA-Interim,JRA-55,and MERRA are more consistent with ADJ than other reanalysis datasets.

关键词： radiosonde air temperature reanalysis data China raw versus homogenized data

Semi-supervised Artificial Immune Mixture Models Clustering

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Chinese Journal of Electronics 2016年第2期25卷 249-255页

作者： HUANG Wenlong WANG Xiaodan LI Guohong KANG Hongxia air and Missile Defense College Air Force Engineering University State Key Laboratory of Astronautic Dynamics Xi'an Satellite Control Center

Learning with partly labeled data aims at combining labeled and unlabeled data in order to boost the accuracy of an algorithm. The traditional Expectation maximization(EM) algorithm only produces locally optimal solutions, it is sensitive to initialization, and the number of components of mixture model must be known in advance. We propose a novel semi-supervised clustering algorithm that uses Gaussian mixture models(GMM) as the underlying clustering model. A novel adaptive global search mechanism is introduced into semi-supervised gaussian mixture model-based clustering, where the EM algorithm is incorporated with the ideas of an immune clonal selection technique. The new algorithm overcomes the various problems associated with the traditional EM algorithm. And it can improve the effectiveness in estimating the parameters and determining the optimal number of clusters automatically. The experimental results illustrate the proposed algorithm provides significantly better clustering results, when compared with other methods of incorporating equivalence constraints.

关键词： Semi-supervised clustering Mixture model Immune clonal selection Globally optimal solution

Relative peripheral refraction and its role in myopia onset in teenage students

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International Journal of Ophthalmology(English edition) 2022年第7期15卷 1108-1115页

作者： Lin-Song Qi Lu Yao Xue-Feng Wang Jin Zhao Yong Liu Teng-Yun Wu Qing-Hong Yang Chen Zhao Zhi-Kang Zou Department of Ophthalmology Air Force Medical CenterBeijing 100142China Department of Physical Examination Cadet Bureau of PLA Air ForceBeijing 100195China Department of Clinic and Research Air Force Medical CenterBeijing 100142China

AIM:To characterize peripheral refraction and its relationship with myopia development in a selected group of male teenage Chinese ***:This 2-year prospective cohort study randomly enrolled 85 non-myopic boys(age,14-16 y)from the Experimental Class of air force in *** peripheral refraction was examined at 0°,±10°,and±20°along the horizontal visual field in the right eye at the baseline and 2-year ***:The incidence of myopia at the 2-year followup was 15.29%(13/85).The baseline central refraction(CR)and peripheral refraction at±10°were significantly lower in students who developed myopia than in those who did not(P0.05).At the 2-year follow-up,the RPR at±10°and 20°nasal was significantly more hyperopic in the myopic group than in the non-myopic *** linear regression analysis indicated that the change in CR was significantly correlated with the changes in RPR at 20°nasal,10°nasal,and 20°*** Logistic regression analysis indicated that the baseline CR[odds ratio(OR):0.092,95%confidence interval(CI):0.012-0.688,P=0.020]and the baseline RPR at 10°nasal(OR:0.182,95%CI:0.042-0.799,P=0.024)were significantly correlated with incident myopia(Omnibus test,χ=10.20,P=0.006).CONCLUSION:CR change is significantly correlated with changes in RPR,and students who develop myopia have more relative peripheral *** baseline CR and relative peripheral hyperopia at 10°nasal are protective of myopia onset.

关键词： relative peripheral hyperopia peripheral refraction incident myopia schoolchildren

Development and Application of an Atmospheric-HydrologicHydraulic Flood Forecasting Model Driven by TIGGE Ensemble Forecasts

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Acta meteorologica Sinica 2012年第1期26卷 93-102页

作者：包红军赵琳娜 Public meteorological Service center China Meteorological Administration National meteorological center China Meteorological Administration

A coupled atmospheric-hydrologic-hydraulic ensemble flood forecasting model, driven by The Observing System Research and Predictability Experiment （THORPEX） Interactive Grand Global Ensemble （TIGGE） data, has been developed for flood forecasting over the Huaihe River. The incorporation of numerical weather prediction （NWP） information into flood forecasting systems may increase forecast lead time from a few hours to a few days. A single NWP model forecast from a single forecast center, however, is insufficient as it involves considerable non-predictable uncertainties and leads to a high number of false alarms. The availability of global ensemble NWP systems through TIGGE offers a new opportunity for flood forecast. The Xinanjiang model used for hydrological rainfall-runoff modeling and the one-dimensional unsteady flow model applied to channel flood routing are coupled with ensemble weather predictions based on the TIGGE data from the Canadian meteorological Centre （CMC）, the European Centre for Medium-Range Weather Forecasts （ECMWF）, the UK Met Office （UKMO）, and the US National centers for Environmental Prediction （NCEP）. The developed ensemble flood forecasting model is applied to flood forecasting of the 2007 flood season as a test case. The test case is chosen over the upper reaches of the Huaihe River above Lutaizi station with flood diversion and retarding areas. The input flood discharge hydrograph from the main channel to the flood diversion area is estimated with the fixed split ratio of the main channel discharge. The flood flow inside the flood retarding area is calculated as a reservoir with the water balance method. The Muskingum method is used for flood routing in the flood diversion area. A probabilistic discharge and flood inundation forecast is provided as the end product to study the potential benefits of using the TIGGE ensemble forecasts. The results demonstrate satisfactory flood forecasting with clear signals of probability of floods up to a f

关键词： ensemble flood forecast TIGGE ensemble predictions Xinanjiang model one-dimensionalunsteady flow model flood diversion and retarding Huaihe River